CN203063709U

CN203063709U - Electromobile power battery voltage monitoring circuit

Info

Publication number: CN203063709U
Application number: CN2012206976875U
Authority: CN
Inventors: 罗敏; 孙卫明; 肖勇; 王志平; 胡战虎; 赵伟
Original assignee: Electric Power Research Institute of Guangdong Power Grid Co Ltd
Current assignee: Electric Power Research Institute of Guangdong Power Grid Co Ltd
Priority date: 2012-12-17
Filing date: 2012-12-17
Publication date: 2013-07-17
Anticipated expiration: 2022-12-17

Abstract

An electromobile power battery voltage monitoring circuit comprises a battery collecting circuit and a main controller used for carrying out communication with the battery collecting circuit and an upper computer. The battery collecting circuit is composed of a series body which is composed of a plurality of integrated chips, wherein the plurality of integrated chips are connected in series. The integrated chips are an integrated circuit integrated with a temperature signal processing module, a battery voltage collecting module and a battery electric quantity balancing module, every two adjacent integrated chips are connected through a single program initiation (SPI) bus, an integrated chip arranged at one end portion of the series body is connected with the main controller through the SPI bus, and a serial interface of the main controller is further connected with a general packet radio service (GPRS) wireless communication module through a MAX232 drive chip. Due to the fact that the battery collecting circuit is composed of a plurality of integrated chips integrated with the temperature signal processing module, the battery voltage collecting module and the battery electric quantity balancing module, the electromobile power battery voltage monitoring circuit is not only capable of meeting the requirementof monitoring the battery voltage of the electromobile by the electromobile, but also capable of effectively reducing the size of a circuit, simplifying line connection, and improving disturbance-resisting capability.

Description

The electric automobile power battery electric voltage observation circuit

Technical field

The utility model relates to a kind of electric automobile power battery electric voltage observation circuit.

Background technology

Along with electronlmobil moves towards commercialization day by day, the importance of electric automobile power battery is also more and more outstanding.Electric automobile power battery is the battery pack that is in series by several battery modules, and each battery module is again to be in series by several cells.The operating voltage of electronlmobil cell generally at 2.0V between the 4.2V, the interval is very narrow, the rangeability that battery dump energy changes the battery terminal voltage cause is very little, therefore the measurement to battery terminal voltage requires to have very high precision.

In addition owing to connect between the cell in the battery pack, fill, in the square electric process, the voltage problem of uneven distribution appears easily, and over-charging of battery, cross and to put the decline that all can cause battery life, even cause burning or explosion accident, cause serious consequence.So present electric automobile power battery electric voltage observation circuit not only requires its survey precision height, but also will have the function of balancing battery electric weight, put phenomenon to prevent over-charging of battery or to cross.Also have, electronlmobil is also restricted to the operating temperature of its electrokinetic cell, so above-mentioned battery voltage supervisory circuit also should have the temperature monitoring part.

Electrokinetic cell electric voltage observation circuit of the prior art generally comprises master controller and battery Acquisition Circuit.The battery Acquisition Circuit comprises a treater and respectively with the battery temperature sampling module of described treater communication, battery electric quantity balance module and be used for gathering the cell pressure acquisition module of every joint monomer battery voltage.Master controller is the core component of entire cell electric voltage observation circuit, and it is mainly used in carrying out communication with described battery Acquisition Circuit and upper computer, receives the data that the battery Acquisition Circuit transmits on the one hand, and the data of gathering are carried out real time operation and condition discrimination ,Each module in the battery Acquisition Circuit transmits control command on the other hand, corresponding data is passed to the control command of described upper computer and reception upper computer.

Aspect the cell pressure collection, the mode that traditional cell pressure acquisition module generally adopts multiple way switch to switch, back level electric resistance partial pressure adopts time-sharing format that the terminal voltage of several cells is sampled by same analog to digital conversion circuit ADC.The advantage of this method is, cost is lower, and a plurality of cells share an ADC, and error is less between the magnitude of voltage, and calibration easily.But also there are a lot of shortcomings in it, asynchronous as the sampling time, the sum of errors deviation of adc circuit can influence the measurement of a plurality of monomer battery voltages, reliability is low, and carry out the employing of battery module voltage and need the huge and complicated wire harness of quantity, cause the installation, maintenance difficulty, anti-electromagnetic interference capability difference etc.

The utility model content

Technical problem to be solved in the utility model is, a kind of battery voltage supervisory circuit with high integration degree is provided, and battery voltage supervisory circuit of the present utility model can effectively dwindle the volume of circuit, simplifies the external cabling of circuit.

Above-mentioned technical matters is achieved through the following technical solutions: a kind of electric automobile power battery electric voltage observation circuit, comprise the battery Acquisition Circuit and be used for the master controller that carries out communication with described battery Acquisition Circuit and upper computer, it is characterized in that, the described battery Acquisition Circuit concatermer that the integrated chip of several series connection is formed of serving as reasons, described integrated chip is one to be integrated with the processes temperature signal module, the cell pressure acquisition module, the integrated circuit of battery electric quantity balance module, link to each other by spi bus between every two adjacent integrated chips, the integrated chip that is in described concatermer one end links to each other with described master controller by spi bus, and a serial interface of described master controller also connects a GPRS wireless communication module by driving chip MAX232.

As preferred implementation of the present utility model, described integrated chip is battery monitoring IC.

Described integrated chip is battery monitoring IC LTC6803.

The utlity model has following beneficial effect: 1) battery Acquisition Circuit of the present utility model is made up of the some integrated chips that are integrated with processes temperature signal module, cell pressure acquisition module, battery electric quantity balance module, not only can satisfy electronlmobil to the requirement of its battery voltage supervisory circuit, and can effectively dwindle the volume of circuit, simplifying circuit connects, improve antijamming capability, make things convenient for the I﹠M of circuit; In addition, master controller of the present utility model is by the communication of GPRS wireless communication module realization with upper computer, the external connection line road that can effectively simplify circuit; Also have, above-mentioned integrated chip adopts series system to link to each other, and only the chip by an end links to each other with master controller, and the more chip of convenient expansion is to adapt to the variation of battery pack scale; Also have, integrated chip in the utility model concatermer links to each other by spi bus, and concatermer has only an end to link to each other with master controller by spi bus, and this structure makes the concatermer other end conveniently connect more integrated chips to adapt to the expansion demand of power battery pack by spi bus;

2) the utility model adopts battery monitoring IC LTC6803 as integrated chip of the present utility model, improved the antijamming capability of circuit, built-in a plurality of A and D converter ADC among each battery monitoring IC LTC6803, the terminal voltage signal of each cell passes through an independently A and D converter ADC, but make the voltage of a plurality of cells of battery Acquisition Circuit synchronized sampling of the present utility model, improved sample rate, also helped and improve the reliability that cell pressure is gathered.

Description of drawings

Fig. 1 is functional block diagram of the present utility model;

Fig. 2 is the peripheral interconnecting wiring diagram of integrated chip LTC-6803 of the present utility model.

The specific embodiment

As shown in Figure 1, electric automobile power battery electric voltage observation circuit of the present utility model comprises the battery Acquisition Circuit and is used for the master controller that carries out communication with battery Acquisition Circuit and upper computer that one serial interface of master controller connects a GPRS wireless communication module by driving chip MAX232.In the present embodiment, master controller adopts the C51 micro controller system, collect the voltage that voltage collection circuit is gathered on the one hand, can judge after the operational analysis whether this cell pressure exceeds specified maximum voltage value and control battery Acquisition Circuit balancing battery voltage, thereby on the other hand the voltage data of battery Acquisition Circuit collection being transferred to the GPRS module by serial interface is sent in the wireless network, thereby realize and the wireless telecommunications that can receive the upper computer of wireless signal, give upper computer to realize complex calculations, further simplified control circuit.

The battery Acquisition Circuit concatermer that the integrated chip of several series connection is formed of serving as reasons, described integrated chip is one to be integrated with the integrated circuit of processes temperature signal module, cell pressure acquisition module, battery electric quantity balance module, as shown in Figure 1, link to each other by spi bus between every two adjacent integrated chips, be in concatermer integrated chip topmost and link to each other with master controller by spi bus, each integrated chip also links to each other with the power battery pack of electronlmobil respectively.

That the described integrated chip in the present embodiment adopts is battery monitoring IC LTC-6803, LTC-6803 is that the completed cell of the second generation monitors IC, built-in 12 A and D converter ADC, an accuracy voltage reference, a high potential input multiplexer and a serial interface.Each LTC-6803 can measure the nearly voltage of 12 joint series-connected cells, and an input multiplexer is connected to one 12 with battery

Figure 2012206976875100002DEST_PATH_IMAGE002

A and D converter ADC.An inside

Voltage reference combines with this ADC, makes LTC-6803 have outstanding accuracy of measurement.

A and D converter ADC compares with the conv of other types, though all be in the process of a conversion input repeatedly to be sampled, carries out filtering or average treatment then to produce digital code output, for a given sampling frequency, A and D converter can be realized the noise suppressing function of Zhuo Chao and can have very strong antijamming capability under complete stability within the single change-over period.

In the LTC-6803 chip, each battery input has a MOSFET source switch that is associated, and MOSFET is used for the battery that overcharges is discharged as battery electric quantity balance module of the present utility model, also can be used for controlling the external balance circuit, thereby realize the equilibrium of battery voltage.LTC-6803 does not determine connection and the shutoff of inner MOSFET, and the connection of inner MOSFET is controlled by master controller fully with turn-offing, and master controller writes a configuration register among the LCT-6803 with the open and close of control MOSFET with numerical value.

LTC-6803 is integrated battery electric quantity balance module and cell pressure acquisition module can it carries out the collection of voltage and the equilibrium of voltage by main controller controls simultaneously.Processes temperature signal module that LTC-6803 is also integrated can receive the input of temperature sensor and thermally dependent resistor, to realize the monitoring to battery operated temperature.

The LTC-6803 chip has a spi bus compatible type serial interface, can adopt the mode of daisy chain that a plurality of LTC-6803 chips are together in series, to monitor the voltage of every joint cell in the long string serial connection battery.The LTC-6803 chip has two groups of serial port pins, be designated as downside and high side, downside and high side ports make it possible to the mode of a plurality of LTC-6803 chips with daisy chain coupled together, when adopting this layout structure, master controller can carry out read-write operation to the LTC-6803 chip of series connection, just looks like that they have formed a long shift register.LTC-6803 is responsible for changing voltage of signals level between downside and the high side ports, with along the upper and lower transmission data of battery pack.According to the spi bus agreement, can read and write data by programming input control order control serial interface, on the one hand the voltage data of gathering is read, can read in the voltage control data on the other hand, the switch of the MOSFET power supply of control LTC-6803 chip internal, be used for the battery that overcharges is discharged, thereby realize the equilibrium of battery voltage.

The LTC-6803 chip can be gathered 10 to 12 road monomer battery voltages and carry out respectively behind the analogue to digital conversion numerical information being stored in its built-in holder, is conducive to improve the speed of voltage acquisition and the reliability of battery voltage measurement.As shown in Figure 2, the peripheral circuit of integrated chip LTC-6803 is very simple, with prior art and indifference.As shown in the figure, wherein pin C1-C12 is the battery voltage measurement pin, is used for the input of monitoring battery voltage, external cell, and every joint cell of serial connection all must have one more than or equal to the common-mode voltage of the cell pressure that is positioned at its below.Pin S1-S12 is balanced control pin, the electric weight that is used for battery in the balancing battery group, if the batteries in the series-connected cell overcharges, then the discharged N-channel MOS FET of the inside of S output can be used for this joint cell discharge, and the maximum conducting resistance of this NMOS is generally 20 Ω.In order to strengthen the heat sinking function of LTC-6803, also can give described NMOS the heat sink resistance of connecting.

LTC-6803 has two groups of serial port pins, be designated as downside and high side, the downside pin is CSBI, SCKI, SDI and SDO, and high side pin is CSBO, SCKO and SDOI, CSBI, SCKI pin perseverance are input, are driven by that LTC-6803 that is positioned at its below in master controller or the concatermer.CSBO, SCKO are permanent in output, can drive that LTC-6803 that wears the side of being located thereon in the disjunctor.In order to communicate between the LTC-6803 of daisy chained connection taking, the high side ports pin (CSBO, SCKO and SDOI) of the LTC-6803 that position is lower should be connected to the corresponding downside port pinout of that LTC-6803 that is adjacent, the position is higher (CSBI, SCKI, SDI and SDO) by high-voltage diode, in this configuration, LTC-6803 adopts electric current (rather than voltage) to communicate.

Claims

1. electric automobile power battery electric voltage observation circuit, comprise the battery Acquisition Circuit and be used for the master controller that carries out communication with described battery Acquisition Circuit and upper computer, it is characterized in that, the described battery Acquisition Circuit concatermer that the integrated chip of several series connection is formed of serving as reasons, described integrated chip is one to be integrated with the processes temperature signal module, the cell pressure acquisition module, the integrated circuit of battery electric quantity balance module, link to each other by spi bus between every two adjacent integrated chips, the integrated chip that is in described concatermer one end links to each other with described master controller by spi bus, and a serial interface of described master controller also connects a GPRS wireless communication module by driving chip MAX232.

2. electric automobile power battery electric voltage observation circuit according to claim 1 is characterized in that, described integrated chip is battery monitoring IC.

3. electric automobile power battery electric voltage observation circuit according to claim 2 is characterized in that, described integrated chip is battery monitoring IC LTC6803.