WO2022244572A1 - Storage battery system, rail car provided therewith, and abnormal cell detection method - Google Patents
Storage battery system, rail car provided therewith, and abnormal cell detection method Download PDFInfo
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- WO2022244572A1 WO2022244572A1 PCT/JP2022/018046 JP2022018046W WO2022244572A1 WO 2022244572 A1 WO2022244572 A1 WO 2022244572A1 JP 2022018046 W JP2022018046 W JP 2022018046W WO 2022244572 A1 WO2022244572 A1 WO 2022244572A1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/44—Methods for charging or discharging
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/48—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/02—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from ac mains by converters
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Definitions
- the present invention relates to a storage battery system useful for efficient operation of storage batteries, a railway vehicle equipped with the same, and an abnormal battery detection method.
- the battery may self-discharge due to deterioration of the battery.
- a storage battery system in which batteries are connected in series, if even one of a plurality of series-connected battery cells is self-discharging, the performance of the entire storage battery system, that is, energy efficiency, is reduced. Therefore, there is a need to detect such self-discharge before it adversely affects the performance of the battery system.
- the storage battery system is equipped with a control device for equalizing the voltage of each battery cell connected in series, i.e. adjusting the battery capacity of each of the plurality of battery cells, so that the individual battery cell It was difficult to detect the minute self-discharge of the battery. In other words, this battery capacity adjustment makes it impossible to detect self-discharge at an early stage. Therefore, there is known a method of determining an abnormal battery when the battery with the lowest voltage, which is the target for capacity adjustment, deviates from the average voltage even after capacity adjustment (Patent Document 1).
- the method for determining an abnormal battery in the technology described in Patent Document 1 has the following two problems. First, it was difficult to capture a change of several mV/day only by monitoring the voltage before and after capacitance adjustment. Second, the cause of the deviation from the average voltage and detected as an abnormal battery is self-discharge, or other causes such as capacity deterioration, etc., and the cause of the abnormality is specified. could not. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a storage battery system capable of early detection of abnormal cells.
- the present invention which solves the above problems, is a storage battery system that operates an assembled battery while adjusting its capacity.
- the present invention can provide a storage battery system capable of early detection of abnormal cells.
- FIG. 4 is a circuit diagram for explaining an individual capacity adjustment circuit for an assembled battery in which n cells are connected in series;
- FIG. 4 is a schematic diagram for explaining passive balancing control;
- 4 is a flowchart showing a procedure for detecting self-discharge abnormality;
- 7 is a graph for explaining an abnormal battery detection method (hereinafter, also referred to as a "detection method") by threshold determination of the target specified number of times/time;
- FIG. 10 is a graph for explaining a detection method based on a variance determination of the number of target designation times/time;
- FIG. 4 is a circuit diagram for explaining an individual capacity adjustment circuit for an assembled battery in which n cells are connected in series;
- FIG. 4 is a schematic diagram for explaining passive balancing control;
- 4 is a flowchart showing a procedure for detecting self-discharge abnormality;
- 7 is a graph for explaining an abnormal battery detection method (hereinafter, also referred to as a "detection method
- FIG. 7 is a graph for explaining a detection method based on balancing time/time threshold determination;
- FIG. 5 is a graph for explaining a detection method based on balancing time and capacity distribution determination;
- FIG. 11 is a graph for explaining determination of variation in capacity deterioration rate (SOHQ);
- FIG. 5 is a graph for explaining a detection method by measuring a voltage deviation that is each cell voltage-average voltage;
- 5 is a graph for explaining a detection method based on deviation determination of each cell voltage;
- 7 is a graph for explaining a detection method from maximum/average/minimum voltage;
- FIG. 3 is a schematic diagram for explaining active balancing control;
- FIG. 3 is a schematic diagram for explaining a specified number of times/time of balancing charging and a detection method based on threshold determination of the capacity/time;
- Embodiment 1 will be described with reference to FIGS. 1 to 6.
- FIG. A second embodiment will be described with reference to FIGS. 7 and 8.
- FIG. Example 3 will be described with reference to FIG. Example 4 will be described with reference to FIGS. 10 and 11.
- FIG. Example 5 will be described with reference to FIG. Example 6 will be described with reference to FIGS. 13 and 14.
- Fig. 1 is a functional block diagram showing the schematic configuration of this system.
- the system shown in FIG. 1 is composed of a host controller 19 and an assembled battery (hereinafter also referred to as a "battery pack") 10 that transmits information through a communication line 18 and controls input and output. be.
- a large number of battery packs 10 are connected in series in order to secure the required voltage and capacity. Prepare.
- the host controller 19 may be considered as an ECU (Electronic Control Unit) mounted on an automobile or the like, or an electronic control device provided to support the operation of a railway vehicle, and system control using an electronic circuit. means a generic term for devices (units) that Here, the host controller 19 transmits information to the battery control device 15 and its subordinate cell controller 12 through the communication line 18 to monitor the battery pack 10 and perform advanced control described later. to control input and output.
- ECU Electronic Control Unit
- the battery control device 15 is subordinate to the host controller 19, and one battery pack 10 is provided with one.
- the battery control device 15 has a plurality of cell controllers 12 subordinate to it, and these cell controllers 12 monitor and control a plurality of battery cells 11 (hereinafter also referred to as “monitoring control” or simply “control”). It is hierarchically structured as follows. In order to monitor the state of each battery cell 11 under its supervision, the cell controller 12 not only detects the voltage via the voltage detection line 13 but also detects the temperature via the thermocouple 14 .
- the cell controller 12 performs balancing control aimed at adjusting the capacity of the battery cells 11 connected in series if there is an imbalance in capacity.
- balancing control aimed at adjusting the capacity of the battery cells 11 connected in series if there is an imbalance in capacity.
- temperature detection as an example, one cell controller 12 monitors only one point.
- the cell controller 12 can simultaneously control a large number of battery cells 11 that are pre-linked control targets. As omitted in FIG. 1 and exemplified in FIG. 2, the cell controller 12 includes an assembled battery in which six cells are connected in series (hereinafter also referred to as “six series”), and 12 more cells in series. It is also possible to monitor connected (hereinafter also referred to as “12 series”) assembled batteries.
- the number of cell controllers 12 is preferably proportional to the number of battery cells 11 connected in series.
- the cell controller 12 receives commands from the battery control device 15 via the communication line 16 to perform balancing control and the like.
- a communication method for that purpose for example, the application of CAN is enumerated in the case of a mobile object.
- the battery control device 15 estimates the state of charge (SOC) and the deterioration rate ( Capacity maintenance rate: SOH (State of Health) Estimation control and allowable power calculation are executed.
- the battery control device 15 transmits information through the communication line 18 to the host controller 19 and controls the input/output of the battery.
- the battery pack 10 and the host controller 19 cooperate with each other through the communication line 18, but they are independent components that can be procured separately.
- the capacity adjustment circuit 23, the cell controller 12, and the battery control device 15 are collectively called a controller. It may be considered that this controller further includes the upper controller 19 .
- a control hierarchy as shown in FIGS. 1 and 2 is constructed.
- FIG. 2 is a circuit diagram for explaining an individual capacity adjustment circuit for an assembled battery in which n cells are connected in series.
- a capacity adjustment (balancing) circuit 23 exists between the six series battery cells 1 to 6 and the cell controller 12 that collectively monitors them.
- the balancing circuit 23 is mainly composed of a transistor 21 such as a MOSFET and a balancing resistor 22 , and one transistor 21 and one balancing resistor 22 are connected in parallel to each battery cell 11 .
- FIG. 3 is a schematic diagram for explaining passive balancing control.
- cell number 4 (cell 4) has the lowest voltage.
- the battery with the lowest voltage in this way is called a balancing target cell.
- Vth the voltage threshold
- balancing control is performed on the target cell 4 .
- cell number 1 and cell number 3 correspond to this.
- the target cell is discharged and the capacity is adjusted to the cell 4, which is the balancing target cell.
- Balancing control in which the capacity is adjusted by discharging to the balancing resistor 22 in this manner is commonly used as a passive balancing control and a method for adjusting the capacity of a nominal battery.
- the target is the battery with the lowest voltage among the n batteries, and all the other n-1 batteries are subjected to the balancing operation.
- all of the battery cells 11 connected in series in this way must be monitored and adjusted appropriately.
- the cell controller 12 communicates to the battery control device 15 information that is associated with all the cell numbers 1 to n and that allows the voltage of each cell to be grasped.
- the battery control device 15 is higher than the cell controller 12 and has a wide control range.
- the cell controller 12 performs only balancing operations on each battery cell 11 .
- FIG. 4 is a flow chart showing a procedure for detecting self-discharge abnormality. As shown in FIG. 4, the self-discharge abnormal cell detection procedure is executed by the battery control device 15 through steps S10 to S17.
- the control is started at step S10, for example, every second as the calculation cycle.
- the battery control device 15 detects each cell voltage and each cell number.
- the battery control device 15 performs this control, it obtains each cell voltage and each cell number through communication from the cell controller 12 .
- the cell with the lowest voltage among all the voltages is detected and set as the minimum voltage value Vmin.
- step S12 the battery control device 15 determines Vmin+voltage threshold ⁇ cell voltage for all cells. If there is a corresponding cell, the process proceeds to step S13, and if there is no corresponding cell, the process proceeds to step S17 to end the calculation.
- step S13 the battery control device 15 starts a balancing operation so that the capacity of the corresponding cell is adjusted by (cell voltage-Vmin), and then proceeds to step S14.
- step S14 the battery control device 15 counts up the number of times designated as the balancing target within a certain period of the cell number with the lowest voltage, and then proceeds to step S15 after counting up the designated number of times/time. .
- step S15 the battery control device 15 determines whether or not this target specified number of times value/time is equal to or less than the target specified number of times threshold value. If this determination is equal to or less than the threshold (Yes), the cell is not an abnormal self-discharge cell, so the process proceeds to step S17 to end the calculation. If there is a cell with a value equal to or greater than the threshold in step S15 (No), the battery control device 15 determines that the cell is a self-discharge abnormal cell in step S16, and then proceeds to end the calculation in step S17. Details of the control contents of steps S14 and S15 will be described with reference to FIG.
- FIG. 5 is a graph for explaining the detection method based on the threshold determination of the target number of designations/time.
- the horizontal axis indicates the cell number
- the vertical axis indicates the target number of designated times per year, for example, as a time interval.
- the target specified number of times is the number of times the battery control device 15 performs the balancing control and the minimum voltage is specified as the target cell.
- cell 4 has a larger number of target designations than the other cells.
- the target specified number of times is greater than the target specified number of times threshold B, that is, if the determination in step S15 in the battery control device 15 exceeds the threshold (No), the cell is determined to be an abnormal cell in step S16. In this manner, the battery control device 15 can detect abnormalities such as self-discharge.
- the target designation count threshold is determined in consideration of variations in power consumption of the cell controller 12 and variations in expected deterioration.
- Balancing control is originally a capacity adjustment function, and is intended to compensate for variations in power consumption and deterioration described above. For example, if the above-described variation occurs for A% of the capacity, and the purpose of the balancing control is to correct it, and the number of times of balancing assumed from A% is B times, the target specified number of times is It must be a value greater than the threshold B.
- the target designation count threshold B is determined by the number of expected balancing operations.
- FIG. 5 clearly shows that only cell 4 is applicable, multiple cells may be applicable.
- the battery control device 15 determines that the cell is a self-discharge abnormal cell in step S16, it sends an alarm signal to the host system 19 or warns the system manager. This is to prompt the replacement of the battery and to inform the user that the operation should be stopped.
- the host system 19 and the battery control device 15 perform such protective control when it is necessary to perform protective control even if the self-discharge abnormal cell does not lead to an immediate danger.
- the system is typically monitored and controlled using the average charge rate obtained from each of the SOCs of all cells 1-n.
- the battery control device 15 determines whether or not the target specified number of times/time is equal to or greater than a certain threshold, but there is also a method of considering variance.
- FIG. 6 is a graph for explaining the detection method based on the variance determination of the target specified number of times/time.
- the horizontal axis indicates the target specified number of times/time
- the vertical axis indicates the number of applicable cells.
- the number of relevant cells is the number of samples that is considered statistically significant, and the variation is ideal, the number of target designations should follow a normal distribution centering on the median value with a variance of 0.
- the distribution C of the number of balancing target designations is assumed to follow this normal distribution, and the variance determination and the like are performed. Since the actual system has complicated variations in operating conditions and components, it can be used as a criterion for judgment although it does not conform to this.
- the variance threshold D is assumed to be a value of 3 ⁇ .
- the number of target designation times with a variance of 3 ⁇ or more is only about 0.1%. Therefore, if there are 96 series-connected batteries, there is a high probability that not even one cell will match.
- FIG. 6 there is statistical rationality in judging this cell as an abnormal cell that deviates significantly from the standard when the corresponding cell exists in the target number of designations of 3 ⁇ or more.
- the dispersion threshold value D should be determined depending on how much dispersion is regarded as abnormal, so it does not need to be 3 ⁇ .
- the following judgment criteria can be added as judgment criteria for self-discharge abnormal cells. That is, both the threshold B for the number of target designations determined by the absolute value of the number of times described in FIG. 5 and the variance threshold D determined by the variance from the median value described in FIG. 6 are satisfied (AND condition). case, the cell may be determined as an abnormal cell. Alternatively, an abnormal cell may be determined when only one of the target designation frequency threshold B and the dispersion threshold D is satisfied (OR condition).
- the battery control device 15 capable of consolidating all cell information determines whether the battery is abnormal based on the specified number of target cells. That is, the battery control device 15 calculates the self-discharge of the battery pack (assembled battery) 10 in which a plurality of battery cells 1 to n are connected in series, and the deviation between the voltage of each battery cell and the average voltage of the assembled battery. , it is determined that self-discharge has occurred when the deviation exceeds a predetermined value.
- the battery control device 15 determines that the cell is an abnormal self-discharge cell in step S16, it sends an alarm signal to the host system 19 or warns the system manager. As a result, the battery control device 15 not only prompts replacement of the abnormal battery but also informs the user that the operation should be stopped.
- Example 1 the target number of times of balancing was used as the control value, but similar information includes the balancing time and the capacity adjusted (discharged) by balancing.
- Such balancing time and the capacity used for its adjustment can be applied to the processing for detecting the difference based on the original performance of the cell before performing the balancing operation, as described in the first embodiment.
- the balancing target number of times of the first embodiment is versatility. not reach.
- FIG. 7 is a graph for explaining a detection method based on balancing time/time threshold determination, in which the horizontal axis indicates the cell number and the vertical axis indicates the balancing time or balancing capacity within a given period. . Based on the fact that the value of the current flowing through the balancing resistors during normal balancing is almost constant, and that there is a correlation between the balancing capacity and time, both are regarded as equivalent indices and displayed on the vertical axis of FIG.
- FIG. 8 is a graph for explaining a detection method based on balancing time and capacity dispersion determination. As shown in FIG. 8, when the balancing time or the capacity is extremely small, that is, for the cell whose dispersion is equal to or less than the dispersion threshold value G on the negative side, abnormality determination is performed in the same manner as in FIG.
- FIG. 9 is a graph for explaining the determination of variations in capacity deterioration rate (SOHQ), in which the horizontal axis indicates the cell number and the vertical axis plots the capacity deterioration rate (SOHQ).
- the capacity deterioration rate is estimated by the battery control device 15 for each cell.
- the existence of SOHQ cells that deviate from the allowable deterioration value H from the average SOHQ (Average SOHQ) can be read.
- the balancing operation when there is no difference in SOHQ despite the large number of times of target specification in balancing control is due to self-discharge rather than deterioration of capacity.
- this system according to the assembled battery system of Example 3 (also referred to as "this system"), it is possible to improve the detection accuracy of self-discharge.
- the control flow is to detect an abnormality of self-discharge when the SOHQ of the cell that reaches the threshold value B of the target number of times specified in FIG. . If the SOHQ of each cell is not determined, a method of substituting, for example, the resistance deterioration rate (SOHR) of each cell is also effective. Moreover, when neither SOHQ nor SOHR of each cell is estimated, a method of using voltage information of each cell as a substitute can also be used.
- SOHQ resistance deterioration rate
- the control flow is to detect an abnormality of self-discharge when the target specified number of times threshold value B or more in FIG. .
- a method for detecting an abnormality based on the deviation of the voltage of the battery cell 11 instead of the value related to balancing control will be described. If information on balancing control cannot be grasped and only the voltage of each cell can be obtained by the battery control device 15, it is necessary to detect the self-discharge abnormality from the cell voltage.
- FIG. 10 is a graph for explaining the detection method by measuring the voltage deviation Vd, which is each cell voltage-average voltage.
- Vd voltage deviation
- FIG. 10 shows the voltage of each cell 1-n.
- FIG. 10 shows an average cell voltage (hereinafter simply referred to as "average voltage") V, which is the average value of the voltages of all cells 1 to n.
- Example 4 detection is performed by measuring the voltage deviation Vd, which is the cell voltage-average voltage, for each cell.
- FIG. 11 shows a voltage deviation moving average Vd' obtained by moving and averaging the voltage deviation Vd using data for one month, for example.
- FIG. 11 is a graph for explaining a detection method based on deviation determination of each cell voltage. As shown in FIG. 11, a simple moving average is assumed here, but the averaging process may be a low-pass filter or any other method.
- the control flow is to detect an abnormality in self-discharge when the voltage deviation moving average Vd' is equal to or greater than the voltage deviation threshold value J. Since the capacity is normally adjusted by balancing with the voltage threshold A, it is difficult to imagine that the voltage deviation moving average Vd' becomes equal to or higher than the voltage threshold A. Therefore, the voltage deviation threshold J is set to a value smaller than the voltage threshold A. By doing so, it is possible to perform detection equivalent to that in the first and second embodiments from the voltage information.
- Embodiment 5 shows a detection method (hereinafter also referred to as "this detection method") for determining an abnormality based only on limited information such as the highest cell voltage, the lowest cell voltage, and the average voltage in this system. Examples 1 to 4 so far have been described on the premise that the software of this detection method is installed in the battery control device 15 . Since the procedure of this detection method may be implemented in the host controller 19 as a program, the fifth embodiment assumes that this detection method is installed in this host controller 19 . Generally, up to the battery control device 15, all the voltage information of each cell can be obtained, but the host controller 19 can obtain only limited information.
- the host controller 19 needs a method of detecting self-discharge abnormality from these limited representative values.
- self-discharge occurs on the scale of several cells. In this system, when several cells as shown by cells 1 and 3 in FIG. , the situation is such that balancing is stopped.
- FIG. 12 is a graph for explaining a detection method from maximum/average/minimum voltages.
- the ⁇ circle> indicates the transition of the maximum voltage value
- the ⁇ triangle> indicates the transition of the average voltage value
- ⁇ A square mark> indicates the transition of the minimum voltage value.
- the rough dashed line indicates the transition of the average voltage value + the maximum voltage deviation threshold M
- the fine dotted line indicates the transition of the average voltage value - the minimum voltage deviation threshold L. It corresponds to the case where ⁇ circle mark> exists inside the rough broken line, the case where ⁇ square mark> exists outside the fine broken line, and the case where judgment formulas (a) and (b) are true. ing. Both the conditions of the judgment formulas (a) and (b) are established at the condition establishment time T. At this timing, the Abnormality announcement counter at the bottom of FIG. 12 starts counting up.
- Active balancing control is a control that enables capacity adjustment without energy loss by transferring energy from a battery with a higher SOC and voltage than the average to a battery with a lower SOC and voltage than the average.
- FIG. 13 is a schematic diagram for explaining active balancing control.
- the energy transfer target voltage P is set to an average voltage value, for example.
- the battery control device 15 performs balancing discharge Z up to the energy transfer target voltage P for the balancing discharge designated cell Q, which is a battery with a voltage higher than the energy transfer target voltage P.
- the battery control device 15 performs balancing charge U up to the energy transfer target voltage P for the balancing charge designated cell S, which is a battery with a voltage lower than the energy transfer target voltage P.
- Embodiment 6 shown in FIG. 13 exemplifies that all cells are discharge designated cells if they are higher than the energy transfer target voltage. However, it is not necessary for all of them to be so, and a control threshold may be provided when there is a deviation of a certain deviation or more.
- a control threshold value may be provided when there is a deviation of a certain deviation or more.
- a configuration in which energy is transferred via a transformer may be provided. They need to be system-configured to transfer energy by the configuration added to the circuit of FIG. 2 as the hardware of cell controller 12 .
- the method using the deviation of each cell voltage as shown in Examples 4 and 5 or the method described in Example 6 is preferable.
- active balancing control energy is transferred by specifying a cell with a low SOC, that is, a cell to which energy is to be transferred. In this case, it is necessary to determine and process this in the cell controller 12, so the balancing charging specified cell and the balancing charging capacity are used as control values.
- the battery control device 15 or the host controller 19 By summing up the number of balancing target designations for this control value by the battery control device 15 or the host controller 19, it is possible to perform processing equivalent to passive balancing control.
- the specified number of times of balancing charging can be substituted for the value corresponding to the specified number of times of balancing target for the lowest voltage used in FIG.
- the horizontal axis indicates the cell number (Cell No.), and the vertical axis indicates the specified number of times/time of balancing charge within a certain period (Balancing charge specified number of times/time) and its balancing charge capacity [Ah]/ Indicates time (Balancing charge capacity [Ah] / hour).
- the specified number of balancing charges or the balancing charge capacity is larger than the balancing charge threshold Y, the abnormal cell is determined.
- detection equivalent to detection in passive balancing control becomes possible by adopting such a detection method.
- trains equipped with on-board storage battery systems can operate at the starting station, terminal station, and in some cases, some intermediate stations even in non-electrified sections where ground facilities such as overhead lines and substations are not installed.
- Charging equipment is provided only at the station, and by charging the storage battery for each charging equipment, it is possible to run the section.
- a storage battery system (this system) according to an embodiment of the present invention can be summarized as follows.
- the present system described in Example 4 operates while controlling the capacity adjustment (balancing) of the assembled battery.
- the system includes an assembled battery, a capacity adjustment circuit 23 , a cell controller (Battery Cell Controllers) 12 , and a battery control device 15 .
- the capacity adjustment circuit 23, the cell controller 12, and the battery control device 15 are collectively called a controller. It may be considered that this controller further includes the upper controller 19 .
- the control hierarchy is constructed as shown in FIGS.
- the assembled battery (battery pack) 10 has a plurality of battery cells 11 connected in series to provide a desired voltage and capacity.
- the capacity adjustment circuit 23 is a lower function of the controller, and adjusts the capacity so as to correct the imbalance between the plurality of battery cells 11 forming the assembled battery 10 .
- Cell controller 12 controls capacity adjustment circuit 23 .
- This cell controller 12 can collect information from all cells 1 to n, constantly monitors the difference from the average voltage of each cell, and always determines that the cell 4 that continues to protrude to the bottom is abnormal. do.
- the battery control device 15 is hierarchically configured above the cell controller 12, and monitors and controls the battery cells 11 while exchanging acquired information indicating the battery state and control commands.
- the battery control device 15 adjusts the capacity of the battery cells 11 (cells 4) of the assembled battery 10 whose voltage exceeds the allowable range indicated by the voltage deviation threshold value J. That is, as shown in FIG. 11 of the fourth embodiment, if there is a battery cell 11 (cell 4) whose voltage deviation is equal to or greater than a predetermined value with respect to the average voltage of the assembled battery 10, the battery control device 15 It is determined that the battery is abnormal due to discharge. According to this system, by estimating from the voltage information of each cell, it is possible to detect abnormal cells with increased self-discharge at an early stage.
- the present system preferably uses the voltage statistical information collected from each battery cell 11 to determine to detect an abnormal battery. That is, the present system calculates the deviation between the voltage of each battery cell 11 and the average voltage of the assembled battery 10, and if the variance of the distribution of the deviation is equal to or greater than a predetermined value, it determines that the battery is abnormal in that self-discharge has occurred. If there is a deviation of 3 ⁇ or more in normal distribution in statistics, it may be determined that the battery is abnormal. In this way, by realizing a rational quality control system based on statistics, it is possible to reduce the waste of replacing items that can still be used, as well as the waste of losing availability when it is too late.
- the capacity adjustment circuit 23 short-circuits the battery cells 11 that are higher than the others, and corrects the imbalance between the plurality of battery cells 11 that make up the assembled battery 10 .
- Passive balancing control may be performed to correct the At this time, the battery control device 15 counts the number of times the voltage reaches the minimum voltage per unit time during execution of this passive balancing control. It is preferable to apply the counted number of times that the voltage becomes the lowest as a criterion for judging that the battery is abnormal.
- This criterion replaces the deviation of the voltage of each battery cell 11 from the average voltage of the assembled battery 10, which was applied in [1] or [2] above. According to the present system that applies such a criterion, it is possible to detect the difference based on the original performance of the cell before performing the balancing operation by utilizing the number of balancing target designations. Therefore, the detection accuracy of this system can be improved more than the conventional method of evaluating the voltage value after balancing.
- the present system described in Example 5 replaces the deviation of the voltage of each battery cell 11 with respect to the average voltage of the assembled battery 10, during capacity adjustment, the average The deviation between the highest cell voltage and the lowest cell voltage and each with respect to voltage may be applied.
- the battery cell 11 whose deviation between the highest cell voltage and the average voltage is equal to or less than a predetermined value, and whose deviation from the average voltage is equal to or greater than a predetermined value and has the lowest cell voltage, it is regarded as an abnormal battery in which self-discharge has occurred. to decide.
- the capacity adjustment circuit 23 may charge the lower battery cell 11 for capacity adjustment and perform active balancing control. good.
- the active balancing control if there is a battery cell 11 in which at least one of the number of times of charging per unit time, the charged capacity, and at least one of them is equal to or greater than a predetermined value, the self-discharging abnormality is detected. Judge it as a battery.
- the battery control device 15 estimates the capacity deterioration rate (SOHQ) of each of the battery cells 1 to n based on the obtained information indicating the battery state. , and an average capacity deterioration rate (average SOHQ) obtained by averaging them for the entire assembled battery.
- SOHQ capacity deterioration rate
- the battery control device 15 detects that self-discharge occurs in any of the battery cells 1 to n. It is preferable to judge that
- the abnormal battery in which self-discharge occurs as in the above [1] By determining that, the accuracy of abnormality detection can be improved. In other words, if the difference in the degree of deterioration of the capacity (SOHQ) is large enough to exceed the range of the allowable deterioration value H, as in [1] above, by determining that the voltage drop is not caused by self-discharge, The accuracy of anomaly detection can be improved. In other words, it is possible to eliminate the waste of false alarms regarding self-discharge, which requires an earlier response.
- SOHQ degree of deterioration
- the capacity deterioration rate (SOHQ) is a phenomenon expected as a specified life of a storage battery, such as a decrease in charge-discharge efficiency under load depending on aging and frequency of use, and can be dealt with by appropriate operation.
- the battery control device 15 is a computer such as a one-chip microcomputer, and by executing a program stored in a memory (not shown), operates an algorithm for estimating the degree of capacity deterioration (SOHQ) and resistance deterioration. good.
- SOHQ degree of capacity deterioration
- the SOHQ estimated in this way may be complemented with voltage information to make it highly accurate. For example, when the battery cell with the maximum voltage and the balancing target are the same, the SOHQ can be estimated more reliably.
- the shape of the computer may be any, and a part of the computer for other purposes may be shared.
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Abstract
In this storage battery system, which operates while adjusting the capacity of a battery pack, the battery pack comprises multiple battery cells connected in series and is provided with a capacity-adjusting controller. The controller acquires the cell state from each of the multiple cells, generates control commands on the basis of the acquired cell states, and, in the process of adjusting the capacity of the battery cells of the battery pack that have a voltage outside the permitted range, determines, by means of the control commands, battery cells with a voltage deviation greater than or equal to a prescribed value with respect to the average voltage of the battery pack to be abnormal cells. Further, the deviation between the voltages of the battery cells and the average voltage of the battery pack may be calculated and a cell may be determined to be abnormal if, for example, the deviation is beyond 3σ in a normal distribution. By this means, an abnormal cell detection method is provided which can detect abnormal cells at an early stage.
Description
本発明は、蓄電池の効率的運用に有用な蓄電池システム、それを備えた鉄道車両、及び異常電池検知方法に関する。
The present invention relates to a storage battery system useful for efficient operation of storage batteries, a railway vehicle equipped with the same, and an abnormal battery detection method.
電池の劣化により、電池が自己放電する可能性がある。電池を直列接続した蓄電池システムでは、直列接続された複数の電池セルのうち1つでも自己放電していると、蓄電池システム全体の性能、すなわちエネルギー効率が低下してしまう。したがって、このような自己放電を、電池システムの性能に悪影響を及ぶ以前に検知する必要がある。
The battery may self-discharge due to deterioration of the battery. In a storage battery system in which batteries are connected in series, if even one of a plurality of series-connected battery cells is self-discharging, the performance of the entire storage battery system, that is, energy efficiency, is reduced. Therefore, there is a need to detect such self-discharge before it adversely affects the performance of the battery system.
また、この自己放電の速度について、劣化の当初段階では数mV/dayオーダの速度であり、それほどの影響もないが、この段階を経ると自己放電速度が数十mV/dayオーダの速度へと急激に上昇して、エネルギー効率が著しく低下する。これを避けるためには、自己放電の速度は、数mV/dayオーダの段階で、検知される必要がある。しかし、電池のコントローラに搭載されている電圧センサは、10mV程度の精度でしかない。
In the initial stage of deterioration, the speed of self-discharge is on the order of several mV/day, and there is no significant effect. It rises sharply and the energy efficiency drops significantly. In order to avoid this, the speed of self-discharge must be detected in the order of several mV/day. However, voltage sensors mounted on battery controllers are only accurate to about 10 mV.
それに加えて、蓄電池システムには、直列接続された各電池セルの電圧を均等化、すなわち、複数の電池セルそれぞれの電池容量を調整するための制御装置が装備されているため、個々の電池セルの微小な自己放電を検知することが困難であった。つまり、この電池容量調整により、自己放電を早期に発見され得ないようになってしまっている。そこで、容量調整目標となった最低電圧の電池が、容量調整後であっても平均電圧から乖離していた場合に、これを異常電池として判定する方法が知られている(特許文献1)。
In addition, the storage battery system is equipped with a control device for equalizing the voltage of each battery cell connected in series, i.e. adjusting the battery capacity of each of the plurality of battery cells, so that the individual battery cell It was difficult to detect the minute self-discharge of the battery. In other words, this battery capacity adjustment makes it impossible to detect self-discharge at an early stage. Therefore, there is known a method of determining an abnormal battery when the battery with the lowest voltage, which is the target for capacity adjustment, deviates from the average voltage even after capacity adjustment (Patent Document 1).
しかしながら、特許文献1に記載の技術における異常電池判定方法には、つぎに示す2点の課題があった。第1に、容量調整前後の電圧を監視するだけでは、数mV/dayの変化を捕捉することが困難であった。第2に、平均電圧から乖離して異常電池として検知された原因が、自己放電であるのか、その他の原因として容量劣化等であるのか、何れの原因によって異常が発生したのか、その原因を特定できなかった。本発明は、上記課題に鑑みてなされたものであり、その目的とするところは、異常セルを早期検知することが可能な蓄電池システムを提供することにある。
However, the method for determining an abnormal battery in the technology described in Patent Document 1 has the following two problems. First, it was difficult to capture a change of several mV/day only by monitoring the voltage before and after capacitance adjustment. Second, the cause of the deviation from the average voltage and detected as an abnormal battery is self-discharge, or other causes such as capacity deterioration, etc., and the cause of the abnormality is specified. could not. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a storage battery system capable of early detection of abnormal cells.
上記課題を解決する本発明は、組電池を容量調整しながら運用する蓄電池システムであって、組電池は、複数の電池セルが直列接続されており、容量調整も可能なコントローラを備え、コントローラは、複数の電池それぞれから電池状態を取得し、取得した電池状態に基づいて制御命令を生成し、制御命令により、組電池のうち許容範囲外の電圧となっている電池セルの容量を調整する過程で、組電池の平均電圧に対し、電圧の偏差が所定値以上の電池セルを異常電池として判断する。
The present invention, which solves the above problems, is a storage battery system that operates an assembled battery while adjusting its capacity. A process of acquiring the battery status from each of a plurality of batteries, generating a control command based on the acquired battery status, and adjusting the capacity of a battery cell whose voltage is outside the allowable range in the assembled battery according to the control command. Then, a battery cell whose voltage deviation is equal to or greater than a predetermined value with respect to the average voltage of the assembled battery is determined as an abnormal battery.
本発明により、異常セルを早期検知することが可能な蓄電池システムを提供できる。
The present invention can provide a storage battery system capable of early detection of abnormal cells.
以下、図面等を用いて、本発明の実施形態について説明する。実施例1は、図1~図6を用いて説明する。実施例2は、図7及び図8を用いて説明する。実施例3は、図9を用いて説明する。実施例4は、図10及び図11を用いて説明する。実施例5は、図12を用いて説明する。実施例6は、図13及び図14を用いて説明する。
Hereinafter, embodiments of the present invention will be described using drawings and the like. Embodiment 1 will be described with reference to FIGS. 1 to 6. FIG. A second embodiment will be described with reference to FIGS. 7 and 8. FIG. Example 3 will be described with reference to FIG. Example 4 will be described with reference to FIGS. 10 and 11. FIG. Example 5 will be described with reference to FIG. Example 6 will be described with reference to FIGS. 13 and 14. FIG.
本発明は、具体例に係る以下の説明に限定されるものではなく、本明細書に開示される技術的思想の範囲内において当業者による様々な変更および修正が可能である。また、本発明を説明するための全図において、同一の機能を有するものは、同一の符号を付け、その重複する説明を省略する場合がある。また、全実施例1~6において、セル番号1~6の電池セル(以下、単に「電池」又は「セル」ともいう)を明示し、それら以外の電池セル7~nについては、記載を省略しているが、それらの電池セル7~nも本発明の適用対象である。
The present invention is not limited to the following description of specific examples, and various changes and modifications are possible by those skilled in the art within the scope of the technical ideas disclosed in this specification. Further, in all the drawings for explaining the present invention, parts having the same functions are denoted by the same reference numerals, and overlapping explanations thereof may be omitted. In addition, in all Examples 1 to 6, battery cells with cell numbers 1 to 6 (hereinafter also simply referred to as "batteries" or "cells") are specified, and descriptions of other battery cells 7 to n are omitted. However, the battery cells 7 to n are also applicable to the present invention.
図1は、本システムの概略構成を示す機能ブロック図である。図1の本システムは、上位コントローラ19と、それから通信線18を通じて情報を伝達し、入出力を制御される組電池(以下、「電池パック(Battery pack)」ともいう)10と、により構成される。電池パック10は、必要な電圧及び容量を確保するため、多数が直列接続されており、それらの調整を目的とするセルコン(Battery Cell Controllers)12と、電池制御装置(Battery control device)15と、を備える。
Fig. 1 is a functional block diagram showing the schematic configuration of this system. The system shown in FIG. 1 is composed of a host controller 19 and an assembled battery (hereinafter also referred to as a "battery pack") 10 that transmits information through a communication line 18 and controls input and output. be. A large number of battery packs 10 are connected in series in order to secure the required voltage and capacity. Prepare.
なお、上位コントローラ19は、自動車等に搭載されるECU(Electronic Control Unit)又は、鉄道車両の運転操作を支援するために具備された電子制御装置と考えても良く、電子回路を用いてシステム制御する装置(ユニット)の総称を意味する。ここで、上位コントローラ19は、電池パック10の用途に応じるべく、通信線18を通じて電池制御装置15及びその下位のセルコン12に情報を伝達し、電池パック10を監視するとともに、後述する高度な制御を実行することにより、入出力を制御する。
The host controller 19 may be considered as an ECU (Electronic Control Unit) mounted on an automobile or the like, or an electronic control device provided to support the operation of a railway vehicle, and system control using an electronic circuit. means a generic term for devices (units) that Here, the host controller 19 transmits information to the battery control device 15 and its subordinate cell controller 12 through the communication line 18 to monitor the battery pack 10 and perform advanced control described later. to control input and output.
電池制御装置15は、上位コントローラ19の下位にあって、1つの電池パック10に1つが配設される。電池制御装置15は、その下位に複数のセルコン12を従属させ、それらのセルコン12が、それぞれ複数の電池セル(Battery cell)11を監視及び制御(以下、「監視制御」又は単に「制御」ともいう)するように、階層構成されている。セルコン12は、その監視下にある各電池セル11の状態を監視するため、電圧検出線13によって電圧を検出するほか、熱電対(thermocouple)14によって温度も検出する。
The battery control device 15 is subordinate to the host controller 19, and one battery pack 10 is provided with one. The battery control device 15 has a plurality of cell controllers 12 subordinate to it, and these cell controllers 12 monitor and control a plurality of battery cells 11 (hereinafter also referred to as "monitoring control" or simply "control"). It is hierarchically structured as follows. In order to monitor the state of each battery cell 11 under its supervision, the cell controller 12 not only detects the voltage via the voltage detection line 13 but also detects the temperature via the thermocouple 14 .
これらの検出結果に基づいて、セルコン12は、多数が直列接続された電池セル11の相互間で容量の不均衡が生じれば、それらの調整を目的とするバランシング制御を実行する。なお、温度検出に関しては、一例として、セルコン12の1つで1点のみを監視するものとする。
Based on these detection results, the cell controller 12 performs balancing control aimed at adjusting the capacity of the battery cells 11 connected in series if there is an imbalance in capacity. As for temperature detection, as an example, one cell controller 12 monitors only one point.
セルコン12は、予め紐づけられた制御対象である多数の電池セル11を同時に制御できる。このセルコン12は、図1で省略して図2で例示するように、6個が直列接続された(以下、「6直列ともいう」)組電池のほか、それ以上の個数として12個が直列接続された(以下、「12直列ともいう」)組電池の監視も可能である。
The cell controller 12 can simultaneously control a large number of battery cells 11 that are pre-linked control targets. As omitted in FIG. 1 and exemplified in FIG. 2, the cell controller 12 includes an assembled battery in which six cells are connected in series (hereinafter also referred to as "six series"), and 12 more cells in series. It is also possible to monitor connected (hereinafter also referred to as “12 series”) assembled batteries.
電池セル11の直列数に比例するセルコン12の個数であることが好ましい。このセルコン12は、通信線16を介して電池制御装置15の指令を受けることにより、バランシング制御等を実行する。そのための通信方式として、例えば、移動体であればCANの適用が列挙される。
The number of cell controllers 12 is preferably proportional to the number of battery cells 11 connected in series. The cell controller 12 receives commands from the battery control device 15 via the communication line 16 to perform balancing control and the like. As a communication method for that purpose, for example, the application of CAN is enumerated in the case of a mobile object.
また、複数のセルコン12相互間も通信線16を繋ぐことで、全部のセルコン12に電池制御装置15からの通信指令を同時に送ることが可能となる。電池制御装置15は、セルコン12から送られてくる各セルの電圧情報や温度情報と、電流センサ17の電流情報と、に基づいて、充電率(SOC:State of Charge)推定と、劣化率(容量維持率:SOH:State of Health)推定制御と、許容電力演算と、を実行する。
Also, by connecting the communication line 16 between the plurality of cell controllers 12, it is possible to send the communication command from the battery control device 15 to all the cell controllers 12 at the same time. The battery control device 15 estimates the state of charge (SOC) and the deterioration rate ( Capacity maintenance rate: SOH (State of Health) Estimation control and allowable power calculation are executed.
それと同時に、電池制御装置15は、上位コントローラ19との通信線18を通じて情報を伝達し、電池の入出力を制御する。なお、図1に示すように、電池パック10と、上位コントローラ19と、は通信線18を介して協働機能するが、両者は個別に調達できる独立の構成品である。ここでは、容量調整回路23、セルコン12、及び電池制御装置15、をまとめてコントローラともいう。このコントローラには、さらに上位コントローラ19まで含めると考えても良い。ここに記載した逆の順、すなわち、上位コントローラ19、電池制御装置15、セルコン12、容量調整回路23の順で、図1及び図2に示すような制御の階層が構成される。
At the same time, the battery control device 15 transmits information through the communication line 18 to the host controller 19 and controls the input/output of the battery. As shown in FIG. 1, the battery pack 10 and the host controller 19 cooperate with each other through the communication line 18, but they are independent components that can be procured separately. Here, the capacity adjustment circuit 23, the cell controller 12, and the battery control device 15 are collectively called a controller. It may be considered that this controller further includes the upper controller 19 . In the reverse order described here, that is, in the order of the host controller 19, the battery control device 15, the cell controller 12, and the capacity adjustment circuit 23, a control hierarchy as shown in FIGS. 1 and 2 is constructed.
図2と図3を用いてバランシング制御を行う回路の例と制御例を示す。図2は、セル数n個が直列接続された組電池に対する個別の容量調整回路を説明するための回路図である。図2に示すように、6直列の電池セル1~6と、それらをまとめて監視するセルコン12と、の間には容量調整(バランシング)回路23が存在する。このバランシング回路23は、主にMOSFET等のトランジスタ21とバランシング抵抗22で構成され、各電池セル11に対してトランジスタ21及びバランシング抵抗22が1つずつ並列に接続されている。
An example of a circuit that performs balancing control and an example of control are shown using FIGS. FIG. 2 is a circuit diagram for explaining an individual capacity adjustment circuit for an assembled battery in which n cells are connected in series. As shown in FIG. 2, a capacity adjustment (balancing) circuit 23 exists between the six series battery cells 1 to 6 and the cell controller 12 that collectively monitors them. The balancing circuit 23 is mainly composed of a transistor 21 such as a MOSFET and a balancing resistor 22 , and one transistor 21 and one balancing resistor 22 are connected in parallel to each battery cell 11 .
バランシング動作例を図3で説明する。図3は、パッシブバランシング制御を説明するための概要図である。図3に示すように、セル番号1~nで特定される各セルのうち、セル番号4(セル4)が最低電圧となっているとする。このように、最低電圧となっている電池をバランシング目標セルと呼ぶこととする。例えば、各セル1~nがバランシング目標セルに対して電圧閾値Vth以上の電圧差が開いた場合に、容量調整が必要と判定し対象とするセル4に対してバランシング制御を実施する。
An example of the balancing operation will be explained with reference to FIG. FIG. 3 is a schematic diagram for explaining passive balancing control. As shown in FIG. 3, among the cells identified by cell numbers 1 to n, cell number 4 (cell 4) has the lowest voltage. The battery with the lowest voltage in this way is called a balancing target cell. For example, when each of the cells 1 to n has a voltage difference equal to or greater than the voltage threshold Vth with respect to the balancing target cell, it is determined that capacity adjustment is necessary, and balancing control is performed on the target cell 4 .
この場合、セル番号1とセル番号3がこれに該当する。これらセル1とセル3に並列となっているトランジスタ21をONし並列するバランシング抵抗22に電流を流すことで対象のセルを放電し、バランシング目標セルであるセル4に容量を合わせる動作を実施する。このようにバランシング抵抗22に放電することで容量を調整するバランシング制御を、パッシブパランシング制御と呼び電池の容量調整方法として一般的に普及している。
In this case, cell number 1 and cell number 3 correspond to this. By turning on the transistor 21 parallel to these cells 1 and 3 and causing a current to flow through the parallel balancing resistor 22, the target cell is discharged and the capacity is adjusted to the cell 4, which is the balancing target cell. . Balancing control in which the capacity is adjusted by discharging to the balancing resistor 22 in this manner is commonly used as a passive balancing control and a method for adjusting the capacity of a nominal battery.
電池パック10において、n直列の本システムではn個のうち、一番電圧の低い電池を目標とし、他のn-1個の電池全てがバランシング動作の対象となる。電池パック10では、このように直列接続された各電池セル11の全てを監視し、適宜に調整する必要がある。
In the battery pack 10, in this n-series system, the target is the battery with the lowest voltage among the n batteries, and all the other n-1 batteries are subjected to the balancing operation. In the battery pack 10, all of the battery cells 11 connected in series in this way must be monitored and adjusted appropriately.
そのため、セルコン12は、全てのセル番号1~nに紐づけられてセル別の電圧が把握できる情報を電池制御装置15へ通信する。電池制御装置15は、セルコン12より上位で制御範囲が広く、セルコン12から得た全てのセル情報を集約可能であり、それらの情報を用いて電池パック10の目標電圧を把握する。その一方で、セルコン12は、各電池セル11に対してバランシング動作のみを実行する。
Therefore, the cell controller 12 communicates to the battery control device 15 information that is associated with all the cell numbers 1 to n and that allows the voltage of each cell to be grasped. The battery control device 15 is higher than the cell controller 12 and has a wide control range. On the other hand, the cell controller 12 performs only balancing operations on each battery cell 11 .
実施例1の本システムでは、容量調整の目標セル指定回数に基づいた検知方法に関して説明する。ここで、電池制御装置15によるバランシング制御の制御フローと共に異常セルの検知手法に関して説明する。図4は、自己放電異常を検知する手順を示すフローチャートである。図4に示すように、自己放電異常セルの検知手順は、電池制御装置15によるステップS10~ステップS17を経て実行される。
In this system of the first embodiment, a detection method based on the number of target cell designations for capacity adjustment will be described. Here, a control flow of balancing control by the battery control device 15 and a method of detecting an abnormal cell will be described. FIG. 4 is a flow chart showing a procedure for detecting self-discharge abnormality. As shown in FIG. 4, the self-discharge abnormal cell detection procedure is executed by the battery control device 15 through steps S10 to S17.
まず、演算周期として、例えば、1秒毎にステップS10となり制御を開始する。つぎに、ステップS11にて、電池制御装置15が各セル電圧(Cell voltage)、各セル番号を検出する。電池制御装置15がこの制御を行う場合にはセルコン12からの通信にて、各セル電圧と各セル番号を入手する。このとき、全電圧の中で一番電圧の低いセルを検出し最低電圧値Vminとする。
First, the control is started at step S10, for example, every second as the calculation cycle. Next, in step S11, the battery control device 15 detects each cell voltage and each cell number. When the battery control device 15 performs this control, it obtains each cell voltage and each cell number through communication from the cell controller 12 . At this time, the cell with the lowest voltage among all the voltages is detected and set as the minimum voltage value Vmin.
つぎに、ステップS12にて、電池制御装置15がVmin+電圧閾値<セル電圧の判定を全セルで行う。該当セルがある場合には、ステップS13へ進み、該当セルがない場合には、ステップS17の演算終了へ進む。ステップS13において、電池制御装置15は、該当セルを(セル電圧-Vmin)分の容量が調整されるように、バランシング動作を開始した後、ステップS14へ進む。ステップS14では、電池制御装置15が、最低電圧となったセル番号のある期間内に、バランシングの目標に指定された回数である、目標指定回数値/時間をカウントアップした後、ステップS15へ進む。
Next, in step S12, the battery control device 15 determines Vmin+voltage threshold<cell voltage for all cells. If there is a corresponding cell, the process proceeds to step S13, and if there is no corresponding cell, the process proceeds to step S17 to end the calculation. In step S13, the battery control device 15 starts a balancing operation so that the capacity of the corresponding cell is adjusted by (cell voltage-Vmin), and then proceeds to step S14. In step S14, the battery control device 15 counts up the number of times designated as the balancing target within a certain period of the cell number with the lowest voltage, and then proceeds to step S15 after counting up the designated number of times/time. .
この目標指定回数値/時間が、目標指定回数閾値以下か否かについて、電池制御装置15が、ステップS15で判定する。この判定が閾値以下(Yes)の場合は、自己放電異常セルでないので、ステップS17の演算終了に進む。電池制御装置15は、ステップS15(No)により、閾値以上のセルがある場合、S16により自己放電異常セルと判定した後、ステップS17の演算終了に進む。図5を用いて、ステップS14、及びステップS15について、制御内容の詳細を説明する。
In step S15, the battery control device 15 determines whether or not this target specified number of times value/time is equal to or less than the target specified number of times threshold value. If this determination is equal to or less than the threshold (Yes), the cell is not an abnormal self-discharge cell, so the process proceeds to step S17 to end the calculation. If there is a cell with a value equal to or greater than the threshold in step S15 (No), the battery control device 15 determines that the cell is a self-discharge abnormal cell in step S16, and then proceeds to end the calculation in step S17. Details of the control contents of steps S14 and S15 will be described with reference to FIG.
図5は、目標指定回数/時間の閾値判定による検知方法を説明するためのグラフである。図5は、横軸にセル番号を示し、縦軸には時間間隔として、例えば1年での目標指定回数を示している。図5に示すように、目標指定回数とは、電池制御装置15におけるバランシング制御時に、最低電圧となり目標セルに指定された回数である。図3と同様に、セル4は他のセルと比較して目標指定回数の多いことが確認できる。
FIG. 5 is a graph for explaining the detection method based on the threshold determination of the target number of designations/time. In FIG. 5, the horizontal axis indicates the cell number, and the vertical axis indicates the target number of designated times per year, for example, as a time interval. As shown in FIG. 5, the target specified number of times is the number of times the battery control device 15 performs the balancing control and the minimum voltage is specified as the target cell. As in FIG. 3, it can be confirmed that cell 4 has a larger number of target designations than the other cells.
この目標指定回数が目標指定回数閾値Bよりも多い場合には、すなわち、電池制御装置15におけるステップS15の判定が閾値を超えた場合(No)は、ステップS16で異常セルと判定する。このようにして、電池制御装置15は、自己放電等の異常を検知することが可能である。目標指定回数閾値は、セルコン12の消費電力のばらつき、想定される劣化のばらつきを考慮して決定される。
If the target specified number of times is greater than the target specified number of times threshold B, that is, if the determination in step S15 in the battery control device 15 exceeds the threshold (No), the cell is determined to be an abnormal cell in step S16. In this manner, the battery control device 15 can detect abnormalities such as self-discharge. The target designation count threshold is determined in consideration of variations in power consumption of the cell controller 12 and variations in expected deterioration.
本来、バランシング制御は容量調整機能であって、前述した消費電力のばらつきや劣化のばらつきを補正するためにある。例えば、前述したばらつきが容量A%分発生し、それを補正することがバランシング制御の目的であった場合、A%から想定されるバランシングの回数がB回であった場合に、目標指定回数は閾値Bよりも大きい値でなければならない。
Balancing control is originally a capacity adjustment function, and is intended to compensate for variations in power consumption and deterioration described above. For example, if the above-described variation occurs for A% of the capacity, and the purpose of the balancing control is to correct it, and the number of times of balancing assumed from A% is B times, the target specified number of times is It must be a value greater than the threshold B.
このように、目標指定回数閾値Bは、想定されるバランシングの動作回数で決定される。図5ではセル4のみ該当しているように明示しているが、複数セルが該当することも有り得る。電池制御装置15は、ステップS16で自己放電異常セルと判定した場合、上位システム19へ警報信号を送信するか、又はシステム責任者に警告する。これは電池の交換を促すほか、運転を停止すべき旨を伝えるためである。
In this way, the target designation count threshold B is determined by the number of expected balancing operations. Although FIG. 5 clearly shows that only cell 4 is applicable, multiple cells may be applicable. When the battery control device 15 determines that the cell is a self-discharge abnormal cell in step S16, it sends an alarm signal to the host system 19 or warns the system manager. This is to prompt the replacement of the battery and to inform the user that the operation should be stopped.
上位システム19及び電池制御装置15は、自己放電異常セルのために即時危険には至らないまでも、保護制御する必要がある場合には、そのように実行する。例えば、本システムは、全セル1~nのSOCそれぞれから得られた充電率の平均値を使用して監視制御されることが通常である。
The host system 19 and the battery control device 15 perform such protective control when it is necessary to perform protective control even if the self-discharge abnormal cell does not lead to an immediate danger. For example, the system is typically monitored and controlled using the average charge rate obtained from each of the SOCs of all cells 1-n.
しかし、この自己放電異常セルの発生が判定された場合、異常なセル4を保護して動作させるため、このセル4の電圧から算出されるSOCを制御値として使用すると良い。特に、充電率0%まで放電するような特殊な場合でも、最も劣化が進んだと推定される異常な電池のSOCを把握しながら、最適制御を可能にするためである。ステップS14、及びステップS15において、電池制御装置15は、目標指定回数値/時間が、ある閾値以上か否かで判定していたが、分散(Variance)を考慮する方法もある。
However, when the occurrence of this self-discharge abnormal cell is determined, in order to protect and operate the abnormal cell 4, it is preferable to use the SOC calculated from the voltage of this cell 4 as a control value. In particular, even in a special case where the battery is discharged to a state of charge of 0%, it is possible to perform optimum control while grasping the SOC of an abnormal battery that is estimated to have deteriorated the most. In steps S14 and S15, the battery control device 15 determines whether or not the target specified number of times/time is equal to or greater than a certain threshold, but there is also a method of considering variance.
図6は、目標指定回数/時間の分散判定による検知方法を説明するためのグラフである。この図6は、横軸に目標指定回数/時間(Target specified number of times / time)を示し、縦軸に該当セル数(Number of applicable cells)を示している。ここで、該当セル数が統計学で有意水準とされる標本数であり、ばらつき等が理想的であれば、目標指定回数は分散0の中央値を中心に正規分布に沿うはずである。図6に示すように、バランシング目標指定回数の分布Cは、この正規分布に従うものと仮定し、分散の判定等を実施する。実際の系では動作条件や構成要素のばらつきが複雑なため、これには沿わないが判定の基準には使用できる。
FIG. 6 is a graph for explaining the detection method based on the variance determination of the target specified number of times/time. In FIG. 6, the horizontal axis indicates the target specified number of times/time, and the vertical axis indicates the number of applicable cells. Here, if the number of relevant cells is the number of samples that is considered statistically significant, and the variation is ideal, the number of target designations should follow a normal distribution centering on the median value with a variance of 0. As shown in FIG. 6, the distribution C of the number of balancing target designations is assumed to follow this normal distribution, and the variance determination and the like are performed. Since the actual system has complicated variations in operating conditions and components, it can be used as a criterion for judgment although it does not conform to this.
実施例1では、分散閾値Dを3σの値と仮定する。正規分布に従う場合、分散3σ以上の目標指定回数は0.1%程度しか存在しないため、電池の直列数が96であった場合には1セルも該当しない確率が高い。しかし、図6で示すように、3σ以上の目標指定回数に該当セルが存在する場合、これを標準から大きく外れた異常セルと判定することに、統計的合理性がある。なお、分散閾値Dに関しては、どこまでの分散を異常ととらえるかによって決定されるべきであるので、3σである必要はない。
In Example 1, the variance threshold D is assumed to be a value of 3σ. When following the normal distribution, the number of target designation times with a variance of 3σ or more is only about 0.1%. Therefore, if there are 96 series-connected batteries, there is a high probability that not even one cell will match. However, as shown in FIG. 6, there is statistical rationality in judging this cell as an abnormal cell that deviates significantly from the standard when the corresponding cell exists in the target number of designations of 3σ or more. It should be noted that the dispersion threshold value D should be determined depending on how much dispersion is regarded as abnormal, so it does not need to be 3σ.
また、自己放電異常セルの判定基準として、ステップS15でしめした判定基準に加えて、つぎのような判定基準も追加することが可能である。すなわち、図5で説明した回数の絶対値で決定される目標指定回数閾値Bと、図6で説明した中央値からの分散で決定される分散閾値Dと、の両方とも成立(AND条件)した場合に、異常セルと判定しても良い。あるいは、目標指定回数閾値Bと、分散閾値Dと、の何れか片方のみ成立(OR条件)した場合に異常セル判定しても良い。
In addition to the judgment criteria shown in step S15, the following judgment criteria can be added as judgment criteria for self-discharge abnormal cells. That is, both the threshold B for the number of target designations determined by the absolute value of the number of times described in FIG. 5 and the variance threshold D determined by the variance from the median value described in FIG. 6 are satisfied (AND condition). case, the cell may be determined as an abnormal cell. Alternatively, an abnormal cell may be determined when only one of the target designation frequency threshold B and the dispersion threshold D is satisfied (OR condition).
従来の組電池システムにおいて、多直列セルの何れかの自己放電を検知する方法として、周知のような、バランシング後の電圧を監視する方法では、バランシング動作で調整された容量分を考慮することが困難であった。また、つぎの2点の課題もあった。第1に、容量調整前後の電圧を監視するだけでは、数mV/dayの変化を捕捉することが困難であった。第2に、平均電圧から乖離して異常電池として検知された原因が、自己放電であるのか、その他の原因として容量劣化等であるのか、何れの原因によって異常が発生したのか、その原因を特定できなかった。
In a conventional assembled battery system, as a method of detecting self-discharge of any of the multiple series cells, a well-known method of monitoring the voltage after balancing can consider the capacity adjusted in the balancing operation. It was difficult. There were also the following two problems. First, it was difficult to capture a change of several mV/day only by monitoring the voltage before and after capacitance adjustment. Second, the cause of the deviation from the average voltage and detected as an abnormal battery is self-discharge, or other causes such as capacity deterioration, etc., and the cause of the abnormality is specified. could not.
本システムにおける異常電池の検出方法は、全てのセル情報を集約可能な電池制御装置15によって、目標セルの指定回数に基づいて異常電池であることを判別する。すなわち、電池制御装置15は、複数の電池セル1~nが直列に接続されている電池パック(組電池)10の自己放電、各電池セルの電圧と組電池の平均電圧との偏差を演算し、偏差が所定値以上となった場合に自己放電が発生したと判断する。
In the method of detecting an abnormal battery in this system, the battery control device 15 capable of consolidating all cell information determines whether the battery is abnormal based on the specified number of target cells. That is, the battery control device 15 calculates the self-discharge of the battery pack (assembled battery) 10 in which a plurality of battery cells 1 to n are connected in series, and the deviation between the voltage of each battery cell and the average voltage of the assembled battery. , it is determined that self-discharge has occurred when the deviation exceeds a predetermined value.
換言すると、複数の電池セル1~nに対し、開路電圧(OCV:Open Circuit Voltage)のバランシング時に、最低セル電圧(バランシング目標セル)となっていた回数が所定値を超えたものがあれば、その電池セルをOCVが低下したものと判断する。このような本システムによれば、バランシングの目標指定回数を活用することで、バランシング動作を行う前のセル本来の性能に基づく差分を検知することが可能となる。そのため、バランシング後の電圧値で評価する従来の方法よりも、本システムの方が検知精度を高められる。
In other words, for a plurality of battery cells 1 to n, when the open circuit voltage (OCV: Open Circuit Voltage) is balanced, if the number of times the minimum cell voltage (balancing target cell) has exceeded a predetermined value, It is determined that the battery cell has a lowered OCV. According to this system, it is possible to detect the difference based on the original performance of the cell before performing the balancing operation by utilizing the target number of times of balancing. Therefore, the detection accuracy of this system can be improved more than the conventional method of evaluating the voltage value after balancing.
その結果、本システムによれば、別の原因による容量劣化等でなく、自己放電であることを検知できる。このように、電池制御装置15は、ステップS16で自己放電異常セルと判定した場合、上位システム19へ警報信号を送信するか、又はシステム責任者に警告する。これにより、電池制御装置15は、異常電池の交換を促すほか、運転を停止すべき旨を伝えられる。
As a result, according to this system, it is possible to detect self-discharge rather than capacity deterioration due to other causes. In this way, when the battery control device 15 determines that the cell is an abnormal self-discharge cell in step S16, it sends an alarm signal to the host system 19 or warns the system manager. As a result, the battery control device 15 not only prompts replacement of the abnormal battery but also informs the user that the operation should be stopped.
実施例1ではバランシング目標回数を制御値としたが、同種の情報としてバランシング時間(Balancing time)やバランシングにて調整された(放電された)容量がある。このようなバランシング時間や、その調整に用いられた容量は、実施例1で説明したように、バランシング動作を行う前のセル本来の性能に基づく差分を検知するための処理に適用できる。ただし、このようなバランシング時間や、その調整に用いられた容量は、セルコン12や電池制御装置15において、通常は把握されないことが多いため、汎用性の点で実施例1のバランシング目標回数には及ばない。
In Example 1, the target number of times of balancing was used as the control value, but similar information includes the balancing time and the capacity adjusted (discharged) by balancing. Such balancing time and the capacity used for its adjustment can be applied to the processing for detecting the difference based on the original performance of the cell before performing the balancing operation, as described in the first embodiment. However, since such a balancing time and the capacity used for its adjustment are usually not grasped in the cell controller 12 and the battery control device 15, the balancing target number of times of the first embodiment is versatility. not reach.
図7は、バランシング時間/時間の閾値判定による検知方法を説明するためのグラフであり、横軸にセル番号を示し、縦軸にある期間内のバランシング時間、もしくはバランシング容量(Balancing capacity)を示す。通常バランシング時にバランシング抵抗に流れる電流値はほぼ一定であり、バランシング容量と時間は相関があることに基づいて、両者を同等の指標とみなして図7の縦軸に表示している。
FIG. 7 is a graph for explaining a detection method based on balancing time/time threshold determination, in which the horizontal axis indicates the cell number and the vertical axis indicates the balancing time or balancing capacity within a given period. . Based on the fact that the value of the current flowing through the balancing resistors during normal balancing is almost constant, and that there is a correlation between the balancing capacity and time, both are regarded as equivalent indices and displayed on the vertical axis of FIG.
図5のバランシング目標指定回数値は、多いほど最低セル電圧に近く、自己放電の進んでいる可能性の高いセルであった。これに対し、図7のバランシング時間もしくは容量は、小さいほど最低セル電圧に近く、バランシング調整の対象外であることを示し、バランシング容量閾値Eよりも小さい場合に異常セル判定を行う。
In FIG. 5, the larger the number of times the balancing target was specified, the closer the cell voltage was to the minimum, and the more likely the cell was to self-discharge. On the other hand, the smaller the balancing time or capacity in FIG. 7 is, the closer to the lowest cell voltage is, indicating that it is not subject to balancing adjustment.
また、図6の目標指定回数に対して3σの分散を適用した例になぞらえて、バランシング時間もしくは容量という数値にも3σの分散を適用することにより、同様の結論を導き出すことが可能である。ここで、図8は、バランシング時間及び容量の分散判定による検知方法を説明するためのグラフである。図8に示すように、バランシング時間もしくは容量が極端に小さい場合、つまり分散として負側の分散閾値G以下となったセルに対し、図7と同様に異常判定を行う。
In addition, it is possible to draw a similar conclusion by applying 3σ variance to the value of balancing time or capacity as well as the example of applying 3σ variance to the target number of designations in FIG. Here, FIG. 8 is a graph for explaining a detection method based on balancing time and capacity dispersion determination. As shown in FIG. 8, when the balancing time or the capacity is extremely small, that is, for the cell whose dispersion is equal to or less than the dispersion threshold value G on the negative side, abnormality determination is performed in the same manner as in FIG.
実施例1や実施例2のように、バランシング制御の目標指定回数や時間、容量によって自己放電セルを特定することは可能であるが、本来容量劣化が進行しているセルを保護するためのバランシング制御であるため、自己放電ではなく容量劣化を誤検知してしまう可能性がある。そのため図9に示すように、例えば容量の劣化率に差がないことを検知することで、自己放電の検知精度を向上することが可能である。図9は、容量劣化率(SOHQ)のばらつき判定を説明するためのグラフであり、横軸にセル番号を示し、縦軸に容量劣化率(SOHQ)をプロットしている。
Although it is possible to identify a self-discharge cell based on the target number of times of balancing control, time, and capacity, as in the first and second embodiments, balancing is performed to protect cells whose capacity deterioration is progressing. Since it is a control, there is a possibility that capacity deterioration, not self-discharge, may be erroneously detected. Therefore, as shown in FIG. 9, it is possible to improve the detection accuracy of self-discharge by detecting, for example, that there is no difference in the deterioration rate of the capacity. FIG. 9 is a graph for explaining the determination of variations in capacity deterioration rate (SOHQ), in which the horizontal axis indicates the cell number and the vertical axis plots the capacity deterioration rate (SOHQ).
容量劣化率は、セル毎に電池制御装置15にて推定しているものとする。図9では、平均SOHQ(Average SOHQ)から劣化許容値Hを逸脱したSOHQのセルの存在が読み取れる。一例として、バランシング制御にて目標指定された回数が多いにも関わらず、SOHQには差がない場合のバランシング動作は、容量の劣化でなく自己放電によることが推定できる。その結果、実施例3の組電池システム(これも「本システム」という)によれば、自己放電の検知精度を向上させることが可能である。
It is assumed that the capacity deterioration rate is estimated by the battery control device 15 for each cell. In FIG. 9, the existence of SOHQ cells that deviate from the allowable deterioration value H from the average SOHQ (Average SOHQ) can be read. As an example, it can be estimated that the balancing operation when there is no difference in SOHQ despite the large number of times of target specification in balancing control is due to self-discharge rather than deterioration of capacity. As a result, according to the assembled battery system of Example 3 (also referred to as "this system"), it is possible to improve the detection accuracy of self-discharge.
条件としては、図5の目標指定回数閾値B以上、且つ目標指定回数閾値BとなったセルのSOHQが劣化許容値H以上であった場合に、自己放電の異常を検知するという制御フローとなる。各セルのSOHQを判定していない場合には、例えば各セルの抵抗劣化率(SOHR)を代用する方法も有効である。また、各セルのSOHQとSOHRの何れも推定していない場合には、各セルの電圧情報から代用する方法も使用できる。
As a condition, the control flow is to detect an abnormality of self-discharge when the SOHQ of the cell that reaches the threshold value B of the target number of times specified in FIG. . If the SOHQ of each cell is not determined, a method of substituting, for example, the resistance deterioration rate (SOHR) of each cell is also effective. Moreover, when neither SOHQ nor SOHR of each cell is estimated, a method of using voltage information of each cell as a substitute can also be used.
例えば、容量劣化が他よりも進行しているセルは、最低電圧となるため、バランシング制御の目標指定されることも多い。しかし、このような劣化セルは、本システムで調整充電されたならば、容量が小さいために最大セル電圧となる。この現象を検知することで、容量劣化のばらつきにより、バランシング制御の目標指定されているのか否かを判別することができる。条件としては、図5の目標指定回数閾値B以上、且つ、その目標指定回数閾値Bとなったセルが最大電圧セルとなることがない場合に、自己放電の異常を検知するという制御フローとなる。
For example, cells with more advanced capacity deterioration than others have the lowest voltage, so they are often designated as targets for balancing control. However, such degraded cells, if conditioned and charged by the present system, have a maximum cell voltage due to their small capacity. By detecting this phenomenon, it is possible to determine whether or not the target of balancing control is specified due to variations in capacity deterioration. As a condition, the control flow is to detect an abnormality of self-discharge when the target specified number of times threshold value B or more in FIG. .
実施例4ではバランシング制御関連の値ではなく電池セル11の電圧の偏差から異常を検知する方法を説明する。バランシング制御に関する情報を把握することができず、各セル電圧のみしか電池制御装置15で入手することができない場合、セル電圧で自己放電異常を検知する必要がある。
In the fourth embodiment, a method for detecting an abnormality based on the deviation of the voltage of the battery cell 11 instead of the value related to balancing control will be described. If information on balancing control cannot be grasped and only the voltage of each cell can be obtained by the battery control device 15, it is necessary to detect the self-discharge abnormality from the cell voltage.
この場合の検知手法を図10と図11を用いて説明する。図10は、各セル電圧-平均電圧である電圧偏差Vdの測定による検知方法を説明するためのグラフである。図10は、各セル1~nの電圧を示している。全セル1~nの電圧の平均値である平均セル電圧(以下、単に「平均電圧」ともいう)Vが図10に示されている。
A detection method in this case will be explained using FIGS. 10 and 11. FIG. FIG. 10 is a graph for explaining the detection method by measuring the voltage deviation Vd, which is each cell voltage-average voltage. FIG. 10 shows the voltage of each cell 1-n. FIG. 10 shows an average cell voltage (hereinafter simply referred to as "average voltage") V, which is the average value of the voltages of all cells 1 to n.
実施例4では、セル電圧-平均電圧である電圧偏差Vdをセル毎に測定することで検知を行う。この電圧偏差Vdを、例えば1ヶ月分のデータで移動平均化した電圧偏差移動平均Vd’を図11に示す。図11は、各セル電圧の偏差判定による検知方法を説明するためのグラフである。図11に示すように、ここでは単純な移動平均と仮定したが、平均化の処理は、ローパスフィルター、その他、何れの方法でも構わない。
In Example 4, detection is performed by measuring the voltage deviation Vd, which is the cell voltage-average voltage, for each cell. FIG. 11 shows a voltage deviation moving average Vd' obtained by moving and averaging the voltage deviation Vd using data for one month, for example. FIG. 11 is a graph for explaining a detection method based on deviation determination of each cell voltage. As shown in FIG. 11, a simple moving average is assumed here, but the averaging process may be a low-pass filter or any other method.
図11では、セル4のみ電圧偏差閾値J以下となっている。電圧偏差閾値Jは、バランシングの制御閾値である電圧閾値Aと近い値に設定することで、バランシング制御がセル4を目標として実行されている可能性が高いことを判断することができる。
In FIG. 11, only cell 4 is equal to or less than the voltage deviation threshold value J. By setting the voltage deviation threshold J to a value close to the voltage threshold A, which is the control threshold for balancing, it is possible to determine that there is a high possibility that the balancing control is being executed with the cell 4 as the target.
条件としては、電圧偏差移動平均Vd’が電圧偏差閾値J以上であった場合に、自己放電の異常を検知するという制御フローとなる。通常、電圧閾値Aでバランシングにより容量が調整されるため、電圧偏差移動平均Vd’が電圧閾値A以上になることは考えにくい。故に、電圧閾Aよりも電圧偏差閾値Jは小さい値に設定する。このようにすることで、電圧情報からも実施例1や2同等の検知が可能となる。
As a condition, the control flow is to detect an abnormality in self-discharge when the voltage deviation moving average Vd' is equal to or greater than the voltage deviation threshold value J. Since the capacity is normally adjusted by balancing with the voltage threshold A, it is difficult to imagine that the voltage deviation moving average Vd' becomes equal to or higher than the voltage threshold A. Therefore, the voltage deviation threshold J is set to a value smaller than the voltage threshold A. By doing so, it is possible to perform detection equivalent to that in the first and second embodiments from the voltage information.
実施例5は、本システムにおいて、最高セル電圧と最低セル電圧と平均電圧といった限られた情報のみに基づいて異常判定する検知方法(以下、「本検知方法」ともいう)を示す。これまでの実施例1~4は、電池制御装置15に本検知方法のソフトを実装するという前提で記載してきた。本検知方法の手順を上位コントローラ19にプログラムとして実装する場合もあり得るため、実施例5では本検知方法がこの上位コントローラ19に実装されることを想定する。一般的に、電池制御装置15までは、各セルの電圧情報を全て得られるが、上位コントローラ19は、限られた情報しか得られない。
Embodiment 5 shows a detection method (hereinafter also referred to as "this detection method") for determining an abnormality based only on limited information such as the highest cell voltage, the lowest cell voltage, and the average voltage in this system. Examples 1 to 4 so far have been described on the premise that the software of this detection method is installed in the battery control device 15 . Since the procedure of this detection method may be implemented in the host controller 19 as a program, the fifth embodiment assumes that this detection method is installed in this host controller 19 . Generally, up to the battery control device 15, all the voltage information of each cell can be obtained, but the host controller 19 can obtain only limited information.
すなわち、上位コントローラ19へは、セル電圧の代表値である、最高電圧値、平均電圧値、及び最低電圧値といった程度の情報が伝搬するのみである。そのため、上位コントローラ19では、限られたこれらの代表値から自己放電異常を検知する手法が必要となる。ここで、自己放電が数セル規模で発生している場合を想定する。本システムにおいて、図3のセル1,3で示すような数セルが平均電圧値から電圧閾値Vthだけ乖離している場合、バランシング動作した後、セル1~n全ての電圧が、電圧閾値Vth以下になると、バランシングを停止するという状況になる。
In other words, only the maximum voltage value, the average voltage value, and the minimum voltage value, which are the representative values of the cell voltages, are transmitted to the host controller 19 . Therefore, the host controller 19 needs a method of detecting self-discharge abnormality from these limited representative values. Here, it is assumed that self-discharge occurs on the scale of several cells. In this system, when several cells as shown by cells 1 and 3 in FIG. , the situation is such that balancing is stopped.
このような場合、図12に示して後述するように、最高電圧値と平均電圧値の偏差が小さいが、最低電圧値と平均電圧値の偏差は大きい、といった状況になる。この状況を検知するためには、下記判定式(a),(b)の両方が同時に成立する条件を適用し、これに該当すれば自己放電を検知することが可能である。
In such a case, as shown in FIG. 12 and described later, the deviation between the highest voltage value and the average voltage value is small, but the deviation between the lowest voltage value and the average voltage value is large. In order to detect this situation, it is possible to apply the condition that both of the following judgment formulas (a) and (b) are satisfied at the same time, and to detect self-discharge if this applies.
(a)最高電圧値-平均電圧値<最高電圧偏差閾値M
(b)平均電圧値-最低電圧値>最低電圧偏差閾値L
また、上記判定式(a),(b)のみでも良いが、これだけでは一時的に判定式(a),(b)が成立した場合でも、過剰に異常判定するといった誤動作もある。このような誤動作を避けるため、上記判定式(a),(b)が連続した場合に限って異常判定すれば、より精度を向上させられる。 (a) maximum voltage value - average voltage value < maximum voltage deviation threshold M
(b) average voltage value - minimum voltage value > minimum voltage deviation threshold L
Further, although only the judgment formulas (a) and (b) may be used, even if the judgment formulas (a) and (b) are temporarily satisfied, malfunctions such as excessive abnormal judgment may occur. In order to avoid such malfunctions, the accuracy can be further improved by making an abnormality determination only when the above determination formulas (a) and (b) are consecutive.
(b)平均電圧値-最低電圧値>最低電圧偏差閾値L
また、上記判定式(a),(b)のみでも良いが、これだけでは一時的に判定式(a),(b)が成立した場合でも、過剰に異常判定するといった誤動作もある。このような誤動作を避けるため、上記判定式(a),(b)が連続した場合に限って異常判定すれば、より精度を向上させられる。 (a) maximum voltage value - average voltage value < maximum voltage deviation threshold M
(b) average voltage value - minimum voltage value > minimum voltage deviation threshold L
Further, although only the judgment formulas (a) and (b) may be used, even if the judgment formulas (a) and (b) are temporarily satisfied, malfunctions such as excessive abnormal judgment may occur. In order to avoid such malfunctions, the accuracy can be further improved by making an abnormality determination only when the above determination formulas (a) and (b) are consecutive.
下記条件(1),(2)に示す異常発令カウンタを導入することでこれを実現できる。
This can be achieved by introducing the anomaly announcement counters shown in the following conditions (1) and (2).
条件(1),判定式(a),(b)の両方が真の場合 且つ 異常発令カウンタ≧異常発令カウンタ閾値Kの場合
When both condition (1) and judgment formulas (a) and (b) are true, and when the error call counter ≥ the error call counter threshold value K
異常発令について
条件(2),判定式(a),(b)の両方が真の場合 且つ 異常発令カウンタ<異常発令カウンタ閾値Kの場合 Regarding anomaly announcement When both condition (2) and judgment formulas (a) and (b) are true and when anomaly announcement counter < anomaly announcement counter threshold value K
条件(2),判定式(a),(b)の両方が真の場合 且つ 異常発令カウンタ<異常発令カウンタ閾値Kの場合 Regarding anomaly announcement When both condition (2) and judgment formulas (a) and (b) are true and when anomaly announcement counter < anomaly announcement counter threshold value K
異常発令カウンタ = 異常発令カウンタ+1
条件(3) 上記以外の場合(判定式(a),(b)の何れかが偽の場合)
異常発令カウンタ = 0 Abnormality issue counter = Abnormality issue counter + 1
Condition (3) Other than the above (when either of judgment formulas (a) and (b) is false)
Abnormal issue counter = 0
条件(3) 上記以外の場合(判定式(a),(b)の何れかが偽の場合)
異常発令カウンタ = 0 Abnormality issue counter = Abnormality issue counter + 1
Condition (3) Other than the above (when either of judgment formulas (a) and (b) is false)
Abnormal issue counter = 0
この検知動作を図12にて説明する。図12は、最高/平均/最低電圧からの検知方法を説明するためのグラフである。図12の上方には、凡例に示すように、<丸印>で最高電圧値(Maximum voltage value)の推移を示し、<三角印>で平均電圧値(Average voltage value)の推移を示し、<四角印>で最低電圧値(Minimum voltage value)の推移を示している。
This detection operation will be explained with reference to FIG. FIG. 12 is a graph for explaining a detection method from maximum/average/minimum voltages. In the upper part of FIG. 12, as shown in the legend, the <circle> indicates the transition of the maximum voltage value, the <triangle> indicates the transition of the average voltage value, and < A square mark> indicates the transition of the minimum voltage value.
また、粗い破線が平均電圧値+最高電圧偏差閾値Mの推移を示し、緻密な点線が平均電圧値-最低電圧偏差閾値Lの推移を示している。粗い破線の内側に<丸印>が存在する場合と、緻密な破線の外側に<四角印>が存在する場合と、判定式(a),(b)が真の場合と、それぞれに対応している。条件成立時間Tに判定式(a),(b)の両方の条件が成立している。このタイミングで図12の下方の異常発令カウンタ(Abnormality announcement counter)はカウントアップを開始する。
Also, the rough dashed line indicates the transition of the average voltage value + the maximum voltage deviation threshold M, and the fine dotted line indicates the transition of the average voltage value - the minimum voltage deviation threshold L. It corresponds to the case where <circle mark> exists inside the rough broken line, the case where <square mark> exists outside the fine broken line, and the case where judgment formulas (a) and (b) are true. ing. Both the conditions of the judgment formulas (a) and (b) are established at the condition establishment time T. At this timing, the Abnormality announcement counter at the bottom of FIG. 12 starts counting up.
これは判定式(a),(b)が成立し、条件(3)の状態から条件(2)の状態の条件に移行したことを示している。条件成立時間Tの後も、判定式(a),(b)は成立しているためカウントアップを継続する。これは条件(2)の状態が継続していることを示している。異常発令時間Nにて、異常発令カウンタが異常発令カウンタ閾値K以上となったため、この時点で異常との検知を上位コントローラ19(図1)に通知する。これは条件(2)の状態から条件(1)の状態に移行したことを示している。このように継続時間を判定に用いることで異常判定の精度を向上することが可能となる。
This indicates that the determination formulas (a) and (b) are established and the state of condition (3) has changed to the state of condition (2). Even after the condition satisfaction time T, the determination formulas (a) and (b) are satisfied, so the count-up continues. This indicates that the state of condition (2) continues. Since the abnormality notification counter becomes equal to or greater than the abnormality notification counter threshold value K at the abnormality notification time N, the host controller 19 (FIG. 1) is notified of the detection of abnormality at this point. This indicates that the state of condition (2) has changed to the state of condition (1). By using the duration time for determination in this way, it is possible to improve the accuracy of abnormality determination.
実施例1、及び実施例2では、パッシブバランシング制御を前提に記載してきたが、アクティブバランシング制御等において、最低電圧値を目標に設定しない場合が存在する。このような場合について、実施例6により説明する。
Although the first and second embodiments have been described on the premise of passive balancing control, there are cases where the minimum voltage value is not set as a target in active balancing control or the like. Example 6 demonstrates such a case.
アクティブバランシング制御とは、SOC及び電圧が平均よりも高い電池から、SOC及び電圧が平均よりも低い電池に、エネルギーを転送することでエネルギーのロスなく容量調整できる制御である。図13は、アクティブバランシング制御を説明するための概要図である。図13において、エネルギー転送目標電圧Pを、例えば平均電圧値に設定する。
Active balancing control is a control that enables capacity adjustment without energy loss by transferring energy from a battery with a higher SOC and voltage than the average to a battery with a lower SOC and voltage than the average. FIG. 13 is a schematic diagram for explaining active balancing control. In FIG. 13, the energy transfer target voltage P is set to an average voltage value, for example.
図13に示すように、このエネルギー転送目標電圧Pよりも高い電圧の電池であるバランシング放電指定セルQに対し、エネルギー転送目標電圧Pまで、電池制御装置15がバランシング放電Zを行う。つぎに、このエネルギー転送目標電圧Pよりも低い電圧の電池であるバランシング充電指定セルSに対し、エネルギー転送目標電圧Pまで、電池制御装置15がバランシング充電Uを行う。
As shown in FIG. 13, the battery control device 15 performs balancing discharge Z up to the energy transfer target voltage P for the balancing discharge designated cell Q, which is a battery with a voltage higher than the energy transfer target voltage P. Next, the battery control device 15 performs balancing charge U up to the energy transfer target voltage P for the balancing charge designated cell S, which is a battery with a voltage lower than the energy transfer target voltage P. FIG.
このようにSOC及び電圧の高い電池からSOC及び電圧の低い電池へエネルギー転送する方式を、アクティブバランシング制御という。図13に示す実施例6では、エネルギー転送目標電圧よりも高ければ、全て放電指定セルのように例示している。しかし、全てがそうである必要はなく、一定偏差以上乖離した場合には、制御閾値を設けても良い。
This method of transferring energy from a battery with a high SOC and voltage to a battery with a low SOC and voltage is called active balancing control. Embodiment 6 shown in FIG. 13 exemplifies that all cells are discharge designated cells if they are higher than the energy transfer target voltage. However, it is not necessary for all of them to be so, and a control threshold may be provided when there is a deviation of a certain deviation or more.
同様に、エネルギー転送目標電圧よりも低ければ、全て充電指定セルのように例示している。しかし、一定偏差以上乖離した場合には、制御閾値を設けても良い。これを実現するシステム構成として、例えば、トランスを介してエネルギーを転送する構成を設けても良い。それらは、セルコン12のハードウェアとして、図2の回路に付加した構成により、エネルギーを転送するようにシステム構成することが必要となる。
Similarly, if it is lower than the energy transfer target voltage, all cells are designated to be charged. However, a control threshold value may be provided when there is a deviation of a certain deviation or more. As a system configuration for realizing this, for example, a configuration in which energy is transferred via a transformer may be provided. They need to be system-configured to transfer energy by the configuration added to the circuit of FIG. 2 as the hardware of cell controller 12 .
前述したように、このアクティブバランシング制御の場合、最低電圧値をバランシングの目標値とせず、平均値を目標にする場合がある。この場合、目標指定回数をカウントアップすると、平均電圧のセルをカウントアップしてしまうため適切ではない。
As described above, in the case of this active balancing control, there are cases where the minimum voltage value is not set as the target value for balancing, but the average value is set as the target. In this case, counting up the number of times of target designation is not appropriate because the cells with the average voltage are counted up.
したがって、実施例4、及び実施例5で示すように、各セル電圧の偏差を使用する方法、もしくは実施例6で説明する方法が好ましい。アクティブバランシング制御では、SOCの低いセル、つまりエネルギー転送先となるセルを指定してエネルギーを転送する。この場合、セルコン12において、これを判別し処理する必要があるため、制御値としてバランシング充電指定セルと、バランシング充電容量と、を使用する。
Therefore, the method using the deviation of each cell voltage as shown in Examples 4 and 5 or the method described in Example 6 is preferable. In active balancing control, energy is transferred by specifying a cell with a low SOC, that is, a cell to which energy is to be transferred. In this case, it is necessary to determine and process this in the cell controller 12, so the balancing charging specified cell and the balancing charging capacity are used as control values.
この制御値を電池制御装置15、もしくは上位コントローラ19によって、バランシング目標指定回数を集計することで、パッシブバランシング制御と同等の処理を行うことが可能である。この場合、図5で使用した最低電圧のバランシング目標指定回数に対応する値として、バランシング充電指定回数を代用可能である。また、図7で使用したバランシング時間、及びバランシング容量に対応する値として、バランシング充電容量を代用することも可能である。
By summing up the number of balancing target designations for this control value by the battery control device 15 or the host controller 19, it is possible to perform processing equivalent to passive balancing control. In this case, the specified number of times of balancing charging can be substituted for the value corresponding to the specified number of times of balancing target for the lowest voltage used in FIG. Also, it is possible to substitute the balancing charge capacity for the values corresponding to the balancing time and the balancing capacity used in FIG.
これについて、図14を用いて説明する。図14は、横軸にセル番号(Cell No.)を、縦軸をある期間内のバランシング充電の指定回数/時間(Balancing charge specified number of times / time)、及びそのバランシング充電容量[Ah]/時間(Balancing charge capacity [Ah] / hour)を示す。図14において、バランシング充電指定回数、又はバランシング充電容量が、バランシング充電閾値(Balancing charge threshold)Yよりも大きい場合に、異常セル判定を行う。アクティブバランシング制御では、このような検知手法とすることでパッシブバランシング制御の検知と同等の検知が可能となる。
This will be explained using FIG. In FIG. 14, the horizontal axis indicates the cell number (Cell No.), and the vertical axis indicates the specified number of times/time of balancing charge within a certain period (Balancing charge specified number of times/time) and its balancing charge capacity [Ah]/ Indicates time (Balancing charge capacity [Ah] / hour). In FIG. 14, when the specified number of balancing charges or the balancing charge capacity is larger than the balancing charge threshold Y, the abnormal cell is determined. In active balancing control, detection equivalent to detection in passive balancing control becomes possible by adopting such a detection method.
[補足1]
自己放電はセル内部の正負電極間の絶縁抵抗が低下することを原因とする。この自己放電は、消費しなくても無負荷電圧が4V→3.9Vに下落するような現象で、内部絶縁不良等が原因である。容量劣化は、負荷時電圧が4V(100%)→3.7V(40%)→2.7V(0%)といった放電経過が本来より早まって、エネルギー容量が低下する性能劣化現象である。 [Supplement 1]
Self-discharge is caused by a decrease in insulation resistance between positive and negative electrodes inside the cell. This self-discharge is a phenomenon in which the no-load voltage drops from 4 V to 3.9 V even without consumption, and is caused by internal insulation failure or the like. Capacity deterioration is a performance deterioration phenomenon in which the discharge progresses faster than originally intended, such as the load voltage 4 V (100%) → 3.7 V (40%) → 2.7 V (0%), and the energy capacity decreases.
自己放電はセル内部の正負電極間の絶縁抵抗が低下することを原因とする。この自己放電は、消費しなくても無負荷電圧が4V→3.9Vに下落するような現象で、内部絶縁不良等が原因である。容量劣化は、負荷時電圧が4V(100%)→3.7V(40%)→2.7V(0%)といった放電経過が本来より早まって、エネルギー容量が低下する性能劣化現象である。 [Supplement 1]
Self-discharge is caused by a decrease in insulation resistance between positive and negative electrodes inside the cell. This self-discharge is a phenomenon in which the no-load voltage drops from 4 V to 3.9 V even without consumption, and is caused by internal insulation failure or the like. Capacity deterioration is a performance deterioration phenomenon in which the discharge progresses faster than originally intended, such as the load voltage 4 V (100%) → 3.7 V (40%) → 2.7 V (0%), and the energy capacity decreases.
パッシブバランシングは、各セルで電圧を揃えるように、平均から40mVくらい外れていれば、高い方のセルを抵抗放電して均等化する。アクティブバランシングは、抵抗放電せずに余分な電力を不足するセルに補充して均等化する。
In passive balancing, if the voltage deviates from the average by about 40 mV, the higher cell is resistively discharged to equalize the voltage in each cell. Active balancing replenishes and equalizes the deficient cells with excess power without resistive discharge.
[補足2]
近年、リチウムイオン電池は、そのエネルギー密度が向上したことにより、電気自動車(EV)の普及を徐々に拡大させた。乗用車タイプのEVは、1充電の走行距離が400kmを超えている。一方、鉄道車両は、1両の質量が30~40tonであり、機器の車載スペースが限られる。このような制約条件に対し、高エネルギー密度と高出力密度を両立するリチウムイオン電池による蓄電池システムを車載した電車(EMU:Electric Multiple-Unit)も導入されている。 [Supplement 2]
In recent years, lithium-ion batteries have gradually expanded the spread of electric vehicles (EVs) due to their improved energy density. Passenger car type EVs can travel over 400 km on a single charge. On the other hand, a railcar has a mass of 30 to 40 tons, and the on-board space for equipment is limited. In response to such constraints, a train (EMU: Electric Multiple-Unit) equipped with a storage battery system using a lithium-ion battery that achieves both high energy density and high output density has been introduced.
近年、リチウムイオン電池は、そのエネルギー密度が向上したことにより、電気自動車(EV)の普及を徐々に拡大させた。乗用車タイプのEVは、1充電の走行距離が400kmを超えている。一方、鉄道車両は、1両の質量が30~40tonであり、機器の車載スペースが限られる。このような制約条件に対し、高エネルギー密度と高出力密度を両立するリチウムイオン電池による蓄電池システムを車載した電車(EMU:Electric Multiple-Unit)も導入されている。 [Supplement 2]
In recent years, lithium-ion batteries have gradually expanded the spread of electric vehicles (EVs) due to their improved energy density. Passenger car type EVs can travel over 400 km on a single charge. On the other hand, a railcar has a mass of 30 to 40 tons, and the on-board space for equipment is limited. In response to such constraints, a train (EMU: Electric Multiple-Unit) equipped with a storage battery system using a lithium-ion battery that achieves both high energy density and high output density has been introduced.
つまり、電車の回生エネルギーの一部を吸収して回生失効を防止する回生エネルギー吸収システムを高性能化する。その結果、1充電で100kmを超える走行を可能とする。さらに、電気式気動車(DEMU:Diesel-Electric Multiple-Unit)の回生エネルギーを吸収し、力行エネルギーをアシストするために、リチウムイオン電池を車載したハイブリッド気動車化も進められている。
In other words, improve the performance of the regenerative energy absorption system that absorbs a portion of the regenerative energy of the train and prevents regeneration loss. As a result, it is possible to travel over 100 km on a single charge. Furthermore, in order to absorb the regenerative energy of an electric diesel-electric multiple-unit (DEMU) and assist the power running energy, a hybrid diesel-powered vehicle equipped with an on-board lithium-ion battery is being developed.
蓄電池システムを車載した電車は、通常の電車システムと比較して、架線、変電所等の地上設備が設けられていない非電化区間であっても、始発駅と終端駅、場合によりいくつかの中間駅のみ充電設備を設け、充電設備毎に蓄電池を充電することによって当該区間を走行することができる。
Compared to ordinary train systems, trains equipped with on-board storage battery systems can operate at the starting station, terminal station, and in some cases, some intermediate stations even in non-electrified sections where ground facilities such as overhead lines and substations are not installed. Charging equipment is provided only at the station, and by charging the storage battery for each charging equipment, it is possible to run the section.
電化路線であっても、蓄電池システムを車載した電車を導入し、支線等で運用頻度の低い路線は、架線、変電所等の地上設備を廃止し、メンテナンスコストを低減できる。このような、蓄電池システムを車載した電車では、一回の充電で所定の距離を走り切るため、高い蓄電率まで充電し、SOCを維持させるようにすることが一般的である。
Even on electrified routes, it is possible to reduce maintenance costs by introducing trains equipped with on-board storage battery systems, and eliminating aboveground equipment such as overhead lines and substations on branches and other infrequently operated routes. Since a train equipped with such a storage battery system runs a predetermined distance on a single charge, it is common to charge the battery to a high storage rate to maintain the SOC.
一方、地上設備の故障時、特に架線停電時は、橋梁上やトンネル内など、乗客の退避が難しい区間での立ち往生を避けるため、一定距離の走行が可能である点で蓄電池システムの導入のニーズは高まりつつある。このように、蓄電池システムを地上設備故障時の車両立ち往生を防ぐことを目的として用いる場合には、万が一発生する故障時に備え、蓄電率が高い状態を長期間維持する必要がある。
On the other hand, there is a need to introduce a storage battery system because it is possible to travel a certain distance in order to avoid being stuck in sections where it is difficult for passengers to evacuate, such as on bridges and tunnels, when ground equipment fails, especially when there is a power outage in the overhead line. is rising. As described above, when the storage battery system is used for the purpose of preventing the vehicle from being stuck in the event of ground facility failure, it is necessary to maintain a high power storage rate for a long period of time in preparation for failures that may occur.
本発明の実施形態に係る蓄電池システム(本システム)は、つぎのように総括できる。
[1]実施例4に記載の本システムは、組電池を容量調整(バランシング)制御しながら運用するものである。本システムは、組電池と、容量調整回路23と、セルコン(Battery Cell Controllers)12と、電池制御装置15と、を備える。なお、容量調整回路23、セルコン12、及び電池制御装置15、をまとめてコントローラともいう。このコントローラには、さらに上位コントローラ19まで含めると考えても良い。ここに記載した逆の順で、図1及び図2に示すような制御の階層が構成される。 A storage battery system (this system) according to an embodiment of the present invention can be summarized as follows.
[1] The present system described in Example 4 operates while controlling the capacity adjustment (balancing) of the assembled battery. The system includes an assembled battery, acapacity adjustment circuit 23 , a cell controller (Battery Cell Controllers) 12 , and a battery control device 15 . Note that the capacity adjustment circuit 23, the cell controller 12, and the battery control device 15 are collectively called a controller. It may be considered that this controller further includes the upper controller 19 . In the reverse order described here, the control hierarchy is constructed as shown in FIGS.
[1]実施例4に記載の本システムは、組電池を容量調整(バランシング)制御しながら運用するものである。本システムは、組電池と、容量調整回路23と、セルコン(Battery Cell Controllers)12と、電池制御装置15と、を備える。なお、容量調整回路23、セルコン12、及び電池制御装置15、をまとめてコントローラともいう。このコントローラには、さらに上位コントローラ19まで含めると考えても良い。ここに記載した逆の順で、図1及び図2に示すような制御の階層が構成される。 A storage battery system (this system) according to an embodiment of the present invention can be summarized as follows.
[1] The present system described in Example 4 operates while controlling the capacity adjustment (balancing) of the assembled battery. The system includes an assembled battery, a
組電池(電池パック)10は、複数の電池セル11が直列接続されて、所望の電圧及び容量を提供する。容量調整回路23は、コントローラの下部機能であり、組電池10を構成する複数の電池セル11相互間の不均衡を是正するように容量調整する。セルコン12は、容量調整回路23を制御する。このセルコン12は、全てのセル1~nから情報を集約可能であり、各セルの平均電圧との差分を常にモニタしておいて、常に一番下にはみ出続けているセル4を異常と判定する。電池制御装置15は、セルコン12の上位に階層構成され、取得した電池状態を示す情報と制御命令とを授受しながら電池セル11を監視及び制御する。
The assembled battery (battery pack) 10 has a plurality of battery cells 11 connected in series to provide a desired voltage and capacity. The capacity adjustment circuit 23 is a lower function of the controller, and adjusts the capacity so as to correct the imbalance between the plurality of battery cells 11 forming the assembled battery 10 . Cell controller 12 controls capacity adjustment circuit 23 . This cell controller 12 can collect information from all cells 1 to n, constantly monitors the difference from the average voltage of each cell, and always determines that the cell 4 that continues to protrude to the bottom is abnormal. do. The battery control device 15 is hierarchically configured above the cell controller 12, and monitors and controls the battery cells 11 while exchanging acquired information indicating the battery state and control commands.
電池制御装置15は、組電池10のうち、電圧偏差閾値Jで示す許容範囲を超えた電圧となっている電池セル11(セル4)を容量調整する。すなわち、電池制御装置15は、実施例4の図11に示すように、組電池10の平均電圧に対し、電圧の偏差が所定値以上の電池セル11があれば(セル4)、それを自己放電が発生した異常電池と判断する。本システムによれば、各セルの電圧情報から推定することにより、自己放電が多くなった異常セルを早期検知することが可能である。
The battery control device 15 adjusts the capacity of the battery cells 11 (cells 4) of the assembled battery 10 whose voltage exceeds the allowable range indicated by the voltage deviation threshold value J. That is, as shown in FIG. 11 of the fourth embodiment, if there is a battery cell 11 (cell 4) whose voltage deviation is equal to or greater than a predetermined value with respect to the average voltage of the assembled battery 10, the battery control device 15 It is determined that the battery is abnormal due to discharge. According to this system, by estimating from the voltage information of each cell, it is possible to detect abnormal cells with increased self-discharge at an early stage.
[2]上記[1]において、本システムは、各電池セル11から収集した電圧の統計情報を使用して異常電池を検出するように判断することが好ましい。すなわち、本システムは、各電池セル11の電圧と組電池10の平均電圧との偏差を演算し、偏差の分布の分散が所定値以上であれば自己放電が発生した異常電池と判断する、例えば統計学でいう正規分布において、3σ以上の偏差があれば、異常電池と判断しても良い。このように、統計学に基づいた合理的な品質管理体制を実現することにより、まだ使えるものを交換する無駄のほか、手遅れになって可用性を損ねるような無駄も低減できる。
[2] In [1] above, the present system preferably uses the voltage statistical information collected from each battery cell 11 to determine to detect an abnormal battery. That is, the present system calculates the deviation between the voltage of each battery cell 11 and the average voltage of the assembled battery 10, and if the variance of the distribution of the deviation is equal to or greater than a predetermined value, it determines that the battery is abnormal in that self-discharge has occurred. If there is a deviation of 3σ or more in normal distribution in statistics, it may be determined that the battery is abnormal. In this way, by realizing a rational quality control system based on statistics, it is possible to reduce the waste of replacing items that can still be used, as well as the waste of losing availability when it is too late.
[3]上記[1]又は[2]の本システムにおいて、容量調整回路23は、他より高い電池セル11を短絡調整させて、組電池10を構成する複数の電池セル11相互間の不均衡を是正するように、パッシブバランシング制御しても良い。このとき電池制御装置15は、このパッシブバランシング制御の実行中には、単位時間あたり最低電圧となった回数を計数する。このように計数された、最低電圧となった回数を異常電池と判断する判定基準に適用すると良い。
[3] In the present system of [1] or [2] above, the capacity adjustment circuit 23 short-circuits the battery cells 11 that are higher than the others, and corrects the imbalance between the plurality of battery cells 11 that make up the assembled battery 10 . Passive balancing control may be performed to correct the At this time, the battery control device 15 counts the number of times the voltage reaches the minimum voltage per unit time during execution of this passive balancing control. It is preferable to apply the counted number of times that the voltage becomes the lowest as a criterion for judging that the battery is abnormal.
この判定基準は、上記[1]又は[2]において適用されていた、組電池10の平均電圧に対する各電池セル11の電圧の偏差に代わる判定基準である。このような判定基準を適用する本システムによれば、バランシングの目標指定回数を活用することで、バランシング動作を行う前のセル本来の性能に基づく差分を検知することが可能となる。そのため、バランシング後の電圧値で評価する従来の方法よりも、本システムの方が検知精度を高められる。
This criterion replaces the deviation of the voltage of each battery cell 11 from the average voltage of the assembled battery 10, which was applied in [1] or [2] above. According to the present system that applies such a criterion, it is possible to detect the difference based on the original performance of the cell before performing the balancing operation by utilizing the number of balancing target designations. Therefore, the detection accuracy of this system can be improved more than the conventional method of evaluating the voltage value after balancing.
[4]上記[1]又は[2]において、組電池10の平均電圧に対する各電池セル11の電圧の偏差に代えて、容量調整における、単位時間あたりの、実行時間、又は調整容量値を適用しても良い。このような判定基準を適用する本システムによれば、上記[3]と同様に、バランシングの目標指定回数を活用することで、バランシング動作を行う前のセル本来の性能に基づく差分を検知することが可能となる。そのため、バランシング後の電圧値で評価する従来の方法よりも、本システムの方が検知精度を高められる。
[4] In the above [1] or [2], instead of the deviation of the voltage of each battery cell 11 from the average voltage of the assembled battery 10, the execution time per unit time or the adjustment capacity value in capacity adjustment is applied. You can According to the present system that applies such determination criteria, similar to [3] above, by utilizing the target number of times of balancing, the difference based on the original performance of the cell before performing the balancing operation can be detected. becomes possible. Therefore, the detection accuracy of this system can be improved more than the conventional method of evaluating the voltage value after balancing.
[5]上記[1]又は[2]において、実施例5に記載の本システムは、組電池10の平均電圧に対する各電池セル11の電圧の偏差に代えて、容量調整の実行中の、平均電圧に対する、最高セル電圧と、最低セル電圧と、それぞれとの偏差を適用しても良い。その場合、最高セル電圧と平均電圧との偏差が所定値以下であり、平均電圧との偏差が所定値以上の最低セル電圧の電池セル11があれば、それを自己放電が発生した異常電池と判断する。
[5] In the above [1] or [2], the present system described in Example 5 replaces the deviation of the voltage of each battery cell 11 with respect to the average voltage of the assembled battery 10, during capacity adjustment, the average The deviation between the highest cell voltage and the lowest cell voltage and each with respect to voltage may be applied. In this case, if there is a battery cell 11 whose deviation between the highest cell voltage and the average voltage is equal to or less than a predetermined value, and whose deviation from the average voltage is equal to or greater than a predetermined value and has the lowest cell voltage, it is regarded as an abnormal battery in which self-discharge has occurred. to decide.
このような本システムによれば、全ての情報が集約できないセルコン12や、その上位コントローラ19で判定する場合にも、良好な判定性能が得られる。例えば、最低電圧、平均電圧、及び最高電圧のみと、いった限られた情報での判定を要する場合がそれに該当する。そのほか、パッシブバランシング制御しても最低電圧対象セルがいつまでも変化せず、電圧閾値程度の乖離状態が長時間にわたって継続し続けているような電池セル11があれば、それを自己放電が発生した異常電池と判断する。
According to this system, good judgment performance can be obtained even when judgment is made by the cell controller 12, which cannot collect all information, or by its upper controller 19. For example, this is the case when determination is required based on limited information such as only the lowest voltage, average voltage, and highest voltage. In addition, if there is a battery cell 11 in which the lowest voltage target cell does not change even under passive balancing control, and a state of deviation of about the voltage threshold continues for a long time, it is considered as an abnormality that self-discharge has occurred. Judge it as a battery.
[6]上記[1]又は[2]において、実施例6に記載したように、容量調整回路23は、容量調整のために他より低い電池セル11に充電調整させてアクティブバランシング制御しても良い。このアクティブバランシング制御の実行中には、単位時間あたりの、充電された回数と、充電された容量と、少なくとも何れかが所定値以上の電池セル11があれば、それを自己放電が発生した異常電池と判断する。
[6] In the above [1] or [2], as described in the sixth embodiment, the capacity adjustment circuit 23 may charge the lower battery cell 11 for capacity adjustment and perform active balancing control. good. During the execution of this active balancing control, if there is a battery cell 11 in which at least one of the number of times of charging per unit time, the charged capacity, and at least one of them is equal to or greater than a predetermined value, the self-discharging abnormality is detected. Judge it as a battery.
これは、上記[1]又は[2]における判定基準として用いた、組電池10の平均電圧に対する各電池セル11の電圧の偏差に代えたものである。パッシブバランシング制御は、良好なセルを短絡調整するため、無駄に電力を消費する。これに対し、本システムのアクティブバランシング制御では、弱ったセルに加勢するので、そのための最適なシステムに構成すれば、調整用の無駄な電力消費を低減できる。
This is in place of the deviation of the voltage of each battery cell 11 from the average voltage of the assembled battery 10, which was used as the criterion in [1] or [2] above. Passive balancing control wastes power by short-circuiting good cells. On the other hand, in the active balancing control of this system, the weakened cells are assisted, so if the optimum system is configured for that purpose, wasteful power consumption for adjustment can be reduced.
[7]上記[1]において、実施例3に記載したように、電池制御装置15は、取得した電池状態を示す情報に基づいて各電池セル1~nの容量劣化率(SOHQ)を推定し、それらを組電池全体で平均した容量劣化率平均値(平均SOHQ)を算出可能であると良い。電池制御装置15は、推定した各電池セル1~nの容量劣化率(SOHQ)が、劣化許容値Hの範囲内に含まれる場合に、自己放電が各電池セル1~nの何れかで発生したと判断することが好ましい。
[7] In the above [1], as described in the third embodiment, the battery control device 15 estimates the capacity deterioration rate (SOHQ) of each of the battery cells 1 to n based on the obtained information indicating the battery state. , and an average capacity deterioration rate (average SOHQ) obtained by averaging them for the entire assembled battery. When the estimated capacity deterioration rate (SOHQ) of each of the battery cells 1 to n is within the range of the allowable deterioration value H, the battery control device 15 detects that self-discharge occurs in any of the battery cells 1 to n. It is preferable to judge that
この実施例3の本システムによれば、組電池の各電池1~nにおける容量の劣化度(SOHQ)に差が少ない場合に限って、上記[1]のように自己放電が発生した異常電池と判断することにより、異常検出の精度を向上できる。つまり、劣化許容値Hの範囲を超えるほどに、容量の劣化度(SOHQ)に差が大きければ、上記[1]のように、自己放電を原因とする電圧低下ではないと判断することにより、異常検出の精度を向上できる。つまり、より早めの対応が必要な自己放電について、誤報の無駄をなくせる。
According to this system of the third embodiment, only when the difference in the degree of deterioration (SOHQ) of the capacity of each of the batteries 1 to n of the assembled battery is small, the abnormal battery in which self-discharge occurs as in the above [1] By determining that, the accuracy of abnormality detection can be improved. In other words, if the difference in the degree of deterioration of the capacity (SOHQ) is large enough to exceed the range of the allowable deterioration value H, as in [1] above, by determining that the voltage drop is not caused by self-discharge, The accuracy of anomaly detection can be improved. In other words, it is possible to eliminate the waste of false alarms regarding self-discharge, which requires an earlier response.
このような本システムによれば、直列接続された組電池10にとって、容量劣化率(SOHQ)が劣化したものよりも、危害の程度が大きい自己放電の傾向に着目した検出ができる。なお、容量劣化率(SOHQ)は、経年劣化や使用頻度に応じて負荷時の充放電効率が低下するといった、蓄電池に規定された寿命として予想される現象であり、相応の運用で対処できる。
According to this system, for the series-connected assembled batteries 10, it is possible to detect the tendency of self-discharge, which is more harmful than the deterioration of the capacity deterioration rate (SOHQ). Note that the capacity deterioration rate (SOHQ) is a phenomenon expected as a specified life of a storage battery, such as a decrease in charge-discharge efficiency under load depending on aging and frequency of use, and can be dealt with by appropriate operation.
しかし、自己放電は、本来あってはならないセル内部の絶縁劣化であり、これを長期間放置すると無負荷時の放電により発熱故障を増大させる、といった深刻な事態も予想される。このように、あってはならない自己放電を、必然的なSOHQと区別し、無負荷時にも早期発見できる本システムは、安全の点で有利である。
However, self-discharge is a deterioration of the insulation inside the cell that should not exist. In this way, the present system, which can distinguish self-discharge, which should not occur, from inevitable SOHQ and detect it early even when there is no load, is advantageous in terms of safety.
なお、電池制御装置15は、1チップマイコン等のコンピュータであり、不図示のメモリに記憶されたプログラムを実行することにより、容量の劣化度(SOHQ)や抵抗劣化を推定するアルゴリズムを作動させると良い。これにより推定されたSOHQを電圧情報で補完して高精度にしても良い。例えば、最大電圧となる電池セルとバランシング目標が同じ場合は、SOHQをより確実に推定できる。さらに、コンピュータの形状はいかなるものでも良く、他の用途のコンピュータの一部を兼用利用しても構わない。
Note that the battery control device 15 is a computer such as a one-chip microcomputer, and by executing a program stored in a memory (not shown), operates an algorithm for estimating the degree of capacity deterioration (SOHQ) and resistance deterioration. good. The SOHQ estimated in this way may be complemented with voltage information to make it highly accurate. For example, when the battery cell with the maximum voltage and the balancing target are the same, the SOHQ can be estimated more reliably. Furthermore, the shape of the computer may be any, and a part of the computer for other purposes may be shared.
[8]上記[1]~[7]に記載の蓄電池システムを鉄道車両に備えることが好ましい。このような鉄道車両の蓄電池システムは、自己放電が多くなった異常セルを早期検知できるので、検知された異常電池のみを交換する、といったメンテナンスを遅滞なく実行すれば、可用性を高められる。
[8] It is preferable to equip a railway vehicle with the storage battery system according to [1] to [7] above. Since such a storage battery system for railway vehicles can detect abnormal cells with excessive self-discharge at an early stage, availability can be improved by performing maintenance without delay, such as replacing only the detected abnormal batteries.
10:電池パック(組電池:Battery pack)、11:電池セル(Battery cell)、12:セルコン(Battery Cell Controllers)、13:電圧検出線(Voltage detection line)、14:熱電対(thermocouple)、15:電池制御装置(Battery control device)、16:通信線(Communication line)、17:電流センサ(Current sensor)、18:上位との通信線(Communication line with higher level)、19:上位コントローラ(Upper controller)、23:容量調整回路(バランシング回路)(Balancing circuit)、21:トランジスタ(Transistor)、22:バランシング抵抗(Balancing resistor)、B:目標指定回数閾値(Target specified number of times threshold)、C:バランシング目標指定回数の分布(Distribution of the number of times the balancing target is specified)、D:バランシング目標指定回数の分散閾値(Variance threshold of the number of times the balancing target is specified)、E:バランシング容量閾値(Balancing capacity threshold)、F:バランシング時間の分布(Balancing time distribution)、G:バランシング時間の分散閾値(Balancing time variance threshold)、H:劣化許容値(Deterioration tolerance)、J:電圧偏差閾値(Voltage deviation threshold)、K:異常発令カウンタ閾値(Abnormal announcement counter threshold)、L:最低電圧偏差閾値(Minimum voltage deviation threshold)、M:最高電圧偏差閾値(Maximum voltage deviation threshold)、N:異常発令時間(Abnormal announcement time)、P:エネルギー転送目標電圧(Energy transfer target voltage)、Q:バランシング放電指定セル(Balancing discharge designated cell)、S:バランシング充電指定セル(Balancing charge designated cell)、T:条件成立時間(Condition fulfillment time)、U:バランシング充電(Balancing charging)、V:平均電圧(Average cell voltage)、Vd:電圧偏差(Voltage deviation)、Vd’:電圧偏差移動平均(Voltage deviation moving average)、Vth:電圧閾値(Voltage threshold)、Y:バランシング充電閾値(Balancing charge threshold)、Z:バランシング放電(Balancing discharge)
10: Battery pack, 11: Battery cell, 12: Battery Cell Controllers, 13: Voltage detection line, 14: Thermocouple, 15 : Battery control device, 16: Communication line, 17: Current sensor, 18: Communication line with higher level, 19: Upper controller ), 23: capacity adjustment circuit (balancing circuit), 21: transistor, 22: balancing resistor, B: target specified number of times threshold, C: balancing Distribution of the number of times the balancing target is specified, D: Variance threshold of the number of times the balancing target is specified, E: Balancing capacity threshold capacity threshold), F: Balancing time distribution, G: Balancing time variance threshold, H: Deterioration tolerance, J: Voltage deviation threshold , K: Abnormal announcement counter threshold, L: Minimum voltage deviation threshold, M: Maximum voltage deviation threshold, N: Abnormal announcement Time (Abnormal announcement time), P: Energy transfer target voltage, Q: Balancing discharge designated cell, S: Balancing charge designated cell, T: Condition satisfied Time (Condition fulfillment time), U: Balancing charging, V: Average cell voltage, Vd: Voltage deviation, Vd': Voltage deviation moving average, Vth : Voltage threshold, Y: Balancing charge threshold, Z: Balancing discharge
10: Battery pack, 11: Battery cell, 12: Battery Cell Controllers, 13: Voltage detection line, 14: Thermocouple, 15 : Battery control device, 16: Communication line, 17: Current sensor, 18: Communication line with higher level, 19: Upper controller ), 23: capacity adjustment circuit (balancing circuit), 21: transistor, 22: balancing resistor, B: target specified number of times threshold, C: balancing Distribution of the number of times the balancing target is specified, D: Variance threshold of the number of times the balancing target is specified, E: Balancing capacity threshold capacity threshold), F: Balancing time distribution, G: Balancing time variance threshold, H: Deterioration tolerance, J: Voltage deviation threshold , K: Abnormal announcement counter threshold, L: Minimum voltage deviation threshold, M: Maximum voltage deviation threshold, N: Abnormal announcement Time (Abnormal announcement time), P: Energy transfer target voltage, Q: Balancing discharge designated cell, S: Balancing charge designated cell, T: Condition satisfied Time (Condition fulfillment time), U: Balancing charging, V: Average cell voltage, Vd: Voltage deviation, Vd': Voltage deviation moving average, Vth : Voltage threshold, Y: Balancing charge threshold, Z: Balancing discharge
Claims (14)
- 組電池を容量調整しながら運用する蓄電池システムであって、
前記組電池は、複数の電池セルが直列接続されており、
前記容量調整も可能なコントローラを備え、
該コントローラは、
前記複数の電池それぞれから電池状態を取得し、取得した電池状態に基づいて制御命令を生成し、
該制御命令により、前記組電池のうち許容範囲外の電圧となっている電池セルの容量を調整する過程で、当該組電池の平均電圧に対し、電圧の偏差が所定値以上の電池セルを異常電池として判断する、
蓄電池システム。 A storage battery system that operates while adjusting the capacity of an assembled battery,
The assembled battery includes a plurality of battery cells connected in series,
Equipped with a controller that can also adjust the capacity,
The controller is
obtaining a battery state from each of the plurality of batteries, generating a control command based on the obtained battery state;
According to the control command, in the process of adjusting the capacity of the battery cells whose voltage is out of the allowable range in the assembled battery, the battery cell whose voltage deviation is a predetermined value or more from the average voltage of the assembled battery is abnormal. judged as a battery,
battery system. - 各電池セルの電圧と前記組電池の前記平均電圧との偏差を演算し、
該偏差の分布の分散が所定値以上であれば自己放電が発生した異常電池と判断する、
請求項1に記載の蓄電池システム。 calculating the deviation between the voltage of each battery cell and the average voltage of the assembled battery;
If the dispersion of the deviation distribution is equal to or greater than a predetermined value, the battery is determined to be an abnormal battery in which self-discharge has occurred.
The storage battery system according to claim 1. - 前記コントローラの下部機能の容量調整回路をさらに有し、
該容量調整回路は、前記容量調整のために他より高い電池セルを短絡調整させてパッシブバランシング制御し、
前記組電池の平均電圧に対する各電池セルの電圧の前記偏差に代えて、
該パッシブバランシング制御の実行中に、単位時間あたり最低電圧となった回数を適用する、
請求項1又は2に記載の蓄電池システム。 further comprising a capacity adjustment circuit for the lower function of the controller;
The capacity adjustment circuit performs passive balancing control by short-circuiting a battery cell higher than others for the capacity adjustment,
Instead of the deviation of the voltage of each battery cell with respect to the average voltage of the assembled battery,
Applying the number of times the voltage is the lowest per unit time during the execution of the passive balancing control,
The storage battery system according to claim 1 or 2. - 前記組電池の平均電圧に対する各電池セルの電圧の前記偏差に代えて、
前記容量調整における、単位時間あたりの、実行時間、又は調整容量値を適用する、
請求項1又は2に記載の蓄電池システム。 Instead of the deviation of the voltage of each battery cell with respect to the average voltage of the assembled battery,
applying an execution time or an adjustment capacity value per unit time in the capacity adjustment;
The storage battery system according to claim 1 or 2. - 前記組電池の平均電圧に対する各電池セルの電圧の前記偏差に代えて、
前記容量調整の実行中の、前記平均電圧に対する、最高セル電圧と、最低セル電圧と、それぞれとの偏差を適用し、
前記最高セル電圧と前記平均電圧との偏差が所定値以下であり、前記平均電圧との偏差が所定値以上の前記最低セル電圧の電池セルがあれば、それを自己放電が発生した異常電池と判断する、
請求項1又は2に記載の蓄電池システム。 Instead of the deviation of the voltage of each battery cell with respect to the average voltage of the assembled battery,
applying the deviation of the highest cell voltage and the lowest cell voltage, respectively, from the average voltage during the performance of the capacity adjustment;
If the deviation between the highest cell voltage and the average voltage is a predetermined value or less, and if there is a battery cell with the lowest cell voltage whose deviation from the average voltage is a predetermined value or more, it is regarded as an abnormal battery in which self-discharge has occurred. to decide,
The storage battery system according to claim 1 or 2. - 前記容量調整回路は、前記容量調整のために他より低い電池セルに充電調整させてアクティブバランシング制御し、
前記組電池の平均電圧に対する各電池セルの電圧の前記偏差に代えて、
前記アクティブバランシング制御の実行中に、単位時間あたりの、充電された回数と、充電された容量と、少なくとも何れかが所定値以上の電池セルがあれば、それを自己放電が発生した異常電池と判断する、
請求項3に記載の蓄電池システム。 the capacity adjustment circuit performs active balancing control by adjusting the charging of battery cells lower than others for the capacity adjustment;
Instead of the deviation of the voltage of each battery cell with respect to the average voltage of the assembled battery,
During execution of the active balancing control, if there is a battery cell with at least one of the number of times of charging per unit time, the charged capacity, and a predetermined value or more, it is regarded as an abnormal battery in which self-discharge has occurred. to decide,
The storage battery system according to claim 3. - 前記コントローラは、取得した前記電池状態を示す情報に基づいて各電池セルの容量劣化率を推定可能であり、
容量劣化率平均値に対する偏差が所定値以下と規定された劣化許容値の範囲内に前記各電池セルの容量劣化率が含まれる場合に、前記各電池セルの何れかで異常が発生したと判断する、
請求項1に記載の蓄電池システム。 The controller is capable of estimating a capacity deterioration rate of each battery cell based on the obtained information indicating the battery state,
Determination that an abnormality has occurred in any of the battery cells when the capacity deterioration rate of each of the battery cells falls within a range of permissible deterioration values in which the deviation from the average capacity deterioration rate is equal to or less than a predetermined value. do,
The storage battery system according to claim 1. - 請求項1~7の何れか1項に記載の蓄電池システムを備えた鉄道車両。 A railway vehicle equipped with the storage battery system according to any one of claims 1 to 7.
- 複数の電池セルが直列接続された組電池をコントローラが容量調整しながら運用する異常電池検知方法であって、
前記コントローラは、取得した電池状態を示す情報と制御命令とを授受しながら前記電池セルを監視及び制御し、
前記コントローラは、前記組電池のうち許容範囲外の電圧となっている電池セルを前記容量調整するとともに、
前記組電池の平均電圧に対し、電圧の偏差が所定値以上の前記電池セルがあれば、それを自己放電が発生した異常電池と判断する、
異常電池検知方法。 An abnormal battery detection method in which a controller operates an assembled battery in which a plurality of battery cells are connected in series while adjusting the capacity,
The controller monitors and controls the battery cells while exchanging information indicating the obtained battery state and control commands,
The controller adjusts the capacity of a battery cell having a voltage outside the allowable range in the assembled battery,
If there is a battery cell whose voltage deviation is equal to or greater than a predetermined value with respect to the average voltage of the assembled battery, it is determined to be an abnormal battery in which self-discharge has occurred.
Abnormal battery detection method. - 各電池セルの電圧と前記組電池の前記平均電圧との偏差を演算し、
該偏差の分布の分散が所定値以上であれば自己放電が発生した異常電池と判断する、
請求項9に記載の異常電池検知方法。 calculating the deviation between the voltage of each battery cell and the average voltage of the assembled battery;
If the dispersion of the deviation distribution is equal to or greater than a predetermined value, the battery is determined to be an abnormal battery in which self-discharge has occurred.
The abnormal battery detection method according to claim 9. - 前記コントローラの下部機能の容量調整回路をさらに有し、
該容量調整回路は、前記容量調整のために他より高い電池セルを短絡調整させてパッシブバランシング制御し、
前記組電池の平均電圧に対する各電池セルの電圧の前記偏差に代えて、
該パッシブバランシング制御の実行中に、単位時間あたり最低電圧となった回数を適用する、
請求項9又は10に記載の異常電池検知方法。 further comprising a capacity adjustment circuit for the lower function of the controller;
The capacity adjustment circuit performs passive balancing control by short-circuiting a battery cell higher than others for the capacity adjustment,
Instead of the deviation of the voltage of each battery cell with respect to the average voltage of the assembled battery,
Applying the number of times the voltage is the lowest per unit time during the execution of the passive balancing control,
The abnormal battery detection method according to claim 9 or 10. - 前記組電池の平均電圧に対する各電池セルの電圧の前記偏差に代えて、
前記容量調整における、単位時間あたりの、実行時間、又は調整容量値を適用する、
請求項9又は10に記載の異常電池検知方法。 Instead of the deviation of the voltage of each battery cell with respect to the average voltage of the assembled battery,
applying an execution time or an adjustment capacity value per unit time in the capacity adjustment;
The abnormal battery detection method according to claim 9 or 10. - 前記組電池の平均電圧に対する各電池セルの電圧の前記偏差に代えて、
前記容量調整の実行中の、前記平均電圧に対する、最高セル電圧と、最低セル電圧と、それぞれとの偏差を適用し、
前記最高セル電圧と前記平均電圧との偏差が所定値以下であり、前記平均電圧との偏差が所定値以上の前記最低セル電圧の電池セルがあれば、それを自己放電が発生した異常電池と判断する、
請求項9又は10に記載の異常電池検知方法。 Instead of the deviation of the voltage of each battery cell with respect to the average voltage of the assembled battery,
applying the deviation of the highest cell voltage and the lowest cell voltage, respectively, from the average voltage during the performance of the capacity adjustment;
If the deviation between the highest cell voltage and the average voltage is a predetermined value or less, and if there is a battery cell with the lowest cell voltage whose deviation from the average voltage is a predetermined value or more, it is regarded as an abnormal battery in which self-discharge has occurred. to decide,
The abnormal battery detection method according to claim 9 or 10. - 前記容量調整回路は、前記容量調整のために他より低い電池セルに充電調整させてアクティブバランシング制御し、
前記組電池の平均電圧に対する各電池セルの電圧の前記偏差に代えて、
前記アクティブバランシング制御の実行中に、単位時間あたりの、充電された回数と、充電された容量と、少なくとも何れかが所定値以上の電池セルがあれば、それを自己放電が発生した異常電池と判断する、
請求項11に記載の異常電池検知方法。
the capacity adjustment circuit performs active balancing control by adjusting the charging of battery cells lower than others for the capacity adjustment;
Instead of the deviation of the voltage of each battery cell with respect to the average voltage of the assembled battery,
During execution of the active balancing control, if there is a battery cell with at least one of the number of times of charging per unit time, the charged capacity, and a predetermined value or more, it is regarded as an abnormal battery in which self-discharge has occurred. to decide,
The method for detecting an abnormal battery according to claim 11.
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