CN110676912A - Charging and discharging circuit controlled by double relays and control method - Google Patents
Charging and discharging circuit controlled by double relays and control method Download PDFInfo
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- CN110676912A CN110676912A CN201911088959.4A CN201911088959A CN110676912A CN 110676912 A CN110676912 A CN 110676912A CN 201911088959 A CN201911088959 A CN 201911088959A CN 110676912 A CN110676912 A CN 110676912A
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- power relay
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- 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
- H02J7/0068—Battery or charger load switching, e.g. concurrent charging and load supply
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- 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
- H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
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- Power Engineering (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention discloses a charge-discharge circuit controlled by double relays and a control method, wherein the charge-discharge circuit comprises: the battery charging and discharging main circuit comprises a battery pack, a current collector RL, a fuse RF, a power relay K1, a power relay K2, a circuit breaker QF and an inverter PCS which are connected in the circuit, and the relay detection control assembly comprises a cross type isolation acquisition circuit, a data processing unit, a control unit and an MCU. The invention can effectively monitor poor contact or adhesion of relay contacts caused by metal oxidation, avoid the out-of-control system protection after the adhesion of single relay contacts, fully utilize the application of relay directionality, exert the arc extinguishing capability of the relay, effectively protect the service life of the relay and ensure that the whole system is safer and more reliable.
Description
Technical Field
The invention relates to the technical field of charge-discharge circuits, in particular to a charge-discharge circuit controlled by double relays and a control method.
Background
In practical application, because of the inconsistency of the voltage, the temperature and the SOC among the batteries, the performance difference of the battery pack of the energy storage battery pack management system even reaches the upper limit and the lower limit of alarm protection, a fault is formed, and a relay acts. This has serious consequences for the system, even the whole system is burnt out, besides the type selection should pay attention to the arc extinguishing device of the device, the system should also adopt the actual effective control measures. In the energy storage battery pack management system, the relays are used as controllable high-voltage and high-current components and parts, and are connected in series in a main loop in a single relay mode, so that the energy storage battery pack management system is simple in structure and easy to control and is widely applied. However, the traditional relay connection mode and the traditional control method have the following defects in practical application, and the contact is easy to be subjected to metal oxidation at the moment of actuation/release of the relay, so that poor contact or adhesion is caused; after the contacts of the single relay are bonded, the system is out of control in protection; the high-power relay contact has directionality and cannot meet the charge-discharge bidirectional working requirement of the system; the double relays are connected in parallel in the reverse direction, so that charging and discharging can be realized, and once a certain contact is oxidized or bonded to cause system runaway, the risk is high, and the reliability is low.
Disclosure of Invention
The invention aims to solve the defects in the prior art and provides a charge-discharge circuit controlled by double relays and a control method.
In order to achieve the purpose, the invention adopts the following technical scheme: a dual relay controlled charge and discharge circuit comprising: the battery charging and discharging main loop and the relay detection control assembly;
the main circuit of the battery charge and discharge consists of a battery pack, a current collector RL, a fuse RF, a power relay K1, a power relay K2, a breaker QF and an inverter PCS which are connected in the circuit;
relay detection control assembly includes that collection circuit, data processing unit, the control unit and MCU are kept apart to the crossing, and the crossing output and the data processing unit that keep apart collection circuit and MCU are connected, and data processing unit output and the control unit connection of electric lines, the output of the control unit and power relay K1, power relay K2's input electric connection.
As a further description of the above technical solution:
the power relay K1 and the power relay K2 are both polar relays, and the inverter PCS is a bidirectional inverter for energy storage.
As a further description of the above technical solution:
the crossed isolation acquisition circuit is used for acquiring the states of the power relay K1 and the power relay K2 in real time, and is also used for transmitting acquired state information to the MCU.
As a further description of the above technical solution:
the MCU is used for analyzing and processing the state information of the relay and issuing a control command in real time according to the system requirement;
the MCU adopts an external power supply mode, improves the efficiency of the control circuit and the voltage constraint of power supply of the control chip, is more flexible to apply, reduces interference and improves the reliability of the control circuit.
As a further description of the above technical solution:
the data processing unit is used for receiving the control command issued by the MCU, processing the control command and transmitting the control command to the control unit;
the control unit is used for receiving the control signal transmitted by the data processing unit and controlling the opening and closing of the power relay K1 and the power relay K2.
A control method of a charge-discharge circuit controlled by double relays comprises a relay detection method and a charge-discharge circuit control method.
As a further description of the above technical solution:
the relay detection method comprises the following steps:
SS 1: when the relay normally enters the main loop for detection, the power relay K1, the power relay K2 and the breaker QF are all in a closed state;
SS 2: the inverter is in a shutdown or standby state, the system opens the power relay K1, closes the power relay K2, detects Uad voltage and judges whether the power relay K1 is bonded or not according to a detection program;
SS 3: and (3) disconnecting the power relay K2, closing the power relay K1, detecting Ubc voltage, judging whether the power relay K2 is bonded or not, and uploading detection data to the MCU for analysis and processing in real time.
As a further description of the above technical solution:
the charge-discharge circuit control method comprises the following steps:
SS 1: when the main loop is in a charging state and is required to be forcibly disconnected, the power relay K2 must be disconnected according to system definition, the system stops working, a cross type isolation acquisition circuit detects a disconnection signal of the power relay K2, and whether the contact performance after the current power relay K2 acts is normal is detected;
SS 2: when the main loop is in a discharging state and is required to be forcibly disconnected, the power relay K1 needs to be disconnected according to system definition, the system stops working, a cross type isolation acquisition circuit detects a disconnection signal of the power relay K1, and whether the contact performance after the current power relay K1 acts is normal is detected;
SS 3: main loop closing process: according to the requirements of the system, after the power relay K1 and the power relay K2 are normally closed, and the power relay K1 and the power relay K2 are normally detected through the system, the system can normally operate, and the next charging and discharging process is started.
As a further description of the above technical solution:
the system in the charge and discharge circuit control method for detecting whether the contact performances of the power relay K1 and the power relay K2 are normal comprises the following steps:
s1: and (3) charging abnormity control and detection:
at the time of t1, when the system works normally, the power relay K1 and the power relay K2 are in a closed state, and the inverter PCS works normally;
at the time of t2, due to system alarm protection, the power relay K2 is opened, a power relay K1 is normally closed, the inverter PCS is in standby or stopped, during the period, the detection circuit automatically tests the contact state of the power relay K2, the detection result is processed by the data unit and then uploaded to the MCU for analysis and processing, the power relay K2 is normal and closed, the power relay K2 is abnormal, the open state is kept, and manual replacement is carried out;
the power relay K2 is detected to be normal at the moment of t3, the power relay K2 is closed, and the inverter PCS can be started to work normally after time delay according to system requirements;
s2: discharge abnormality control and detection:
at the time of t1, when the system normally works, the power relay K1 and the power relay K2 are in a closed state, and the PCS normally works.
At the time of t2, due to system alarm protection, the power relay K1 acts to be disconnected, the power relay K2 is normally closed, and the PCS is in standby or stopped. Therein, the
In the period, the detection circuit automatically tests the contact state of the power relay K1, the detection result is processed by the data unit and then uploaded to the MCU for analysis and processing, the power relay K1 is normal and closed, and the power relay K1 is abnormal, keeps an open state and is manually replaced;
and (4) detecting that the power relay K1 is normal and closed at the time of t3, and delaying to start the PCS to normally work according to the system requirement.
Advantageous effects
The invention provides a charge-discharge circuit controlled by double relays and a control method. The method has the following beneficial effects:
the charge-discharge circuit controlled by the double relays can effectively monitor poor contact or adhesion of relay contacts due to metal oxidation, system protection out of control after adhesion of single relay contacts is avoided, directional application of the relays is fully utilized, arc extinguishing capability of the relays is exerted, service lives of the relays are effectively protected, the whole system is safer and more reliable, and the charge-discharge circuit controlled by the double relays is controlled by a control method, management and control on the relays in a time sequence are carried out, application range of the polar relays is widened, speed of response of system control is increased, product cost is saved, arc extinguishing capability of the relays is improved, application of the charge-discharge circuit controlled by the double relays in an actual system is really realized, and real value of the whole system in safety, reliability and flexibility is realized.
Drawings
Fig. 1 is a system structure block diagram of a charge-discharge circuit controlled by a double relay and a control method provided by the invention;
FIG. 2 is a logic diagram of a relay according to the present invention;
FIG. 3 is a logic timing diagram of a relay according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
As shown in fig. 1 to 3, a charge and discharge circuit controlled by a dual relay includes: the battery charging and discharging main loop and the relay detection control assembly;
the main circuit of battery charging and discharging is composed of a battery pack, a current collector RL, a fuse RF, a power relay K1, a power relay K2, a breaker QF and an inverter PCS which are connected in the circuit;
in the charging and discharging process of the battery pack, bidirectional current exists in the actual circuit work, namely a charging loop and a discharging loop, a power relay K1 and a power relay K2 are respectively connected into a positive power line and a negative power line in a main loop, and due to the performance difference of relay parameters, the power relay K1 and the power relay K2 cannot be disconnected or closed at the same time, so that the impact stress of large current and voltage of the main loop is effectively avoided;
relay detection control assembly includes that collection circuit, data processing unit, the control unit and MCU are kept apart to the crossing, and the crossing output and the data processing unit of keeping apart collection circuit and MCU are connected, and data processing unit output and the control unit connection of electric lines, the output of the control unit and power relay K1, power relay K2's input electric connection.
The power relay K1 and the power relay K2 are both polar relays, have the advantages of good arc extinguishing performance, high opening and closing speed and the like, realize the quick response control of the circuit and the safety and reliability of a system, and the PCS is a bidirectional inverter for energy storage.
The cross-type isolation acquisition circuit is used for acquiring the states of the power relay K1 and the power relay K2 in real time, and is also used for transmitting acquired state information to the MCU.
The MCU is used for analyzing and processing the state information of the relay and issuing a control command in real time according to the system requirement;
MCU adopts outside power supply mode, improves control circuit efficiency itself and the voltage constraint of control chip power supply, uses more in a flexible way, and the interference reduces, increases control circuit reliability.
The data processing unit is used for receiving the control command issued by the MCU, processing the control command and transmitting the control command to the control unit;
the control unit is used for receiving the control signal transmitted by the data processing unit and controlling the opening and closing of the power relay K1 and the power relay K2.
A control method of a charge-discharge circuit controlled by double relays comprises a relay detection method and a charge-discharge circuit control method.
The relay detection method comprises the following steps:
SS 1: when the relay normally enters the main loop for detection, the power relay K1, the power relay K2 and the breaker QF are all in a closed state;
SS 2: the inverter is in a shutdown or standby state, the system opens the power relay K1, closes the power relay K2, detects Uad voltage and judges whether the power relay K1 is bonded or not according to a detection program;
SS 3: and (3) disconnecting the power relay K2, closing the power relay K1, detecting Ubc voltage, judging whether the power relay K2 is bonded or not, and uploading detection data to the MCU for analysis and processing in real time.
The charge-discharge circuit control method comprises the following steps:
SS 1: when the main loop is in a charging state and is required to be forcibly disconnected, the power relay K2 must be disconnected according to system definition, the system stops working, a cross type isolation acquisition circuit detects a disconnection signal of the power relay K2, and whether the contact performance after the current power relay K2 acts is normal is detected;
SS 2: when the main loop is in a discharging state and is required to be forcibly disconnected, the power relay K1 needs to be disconnected according to system definition, the system stops working, a cross type isolation acquisition circuit detects a disconnection signal of the power relay K1, and whether the contact performance after the current power relay K1 acts is normal is detected;
SS 3: main loop closing process: according to the requirements of the system, after the power relay K1 and the power relay K2 are normally closed, and the power relay K1 and the power relay K2 are normally detected through the system, the system can normally operate, and the next charging and discharging process is started.
The system detects the open (close) state of the relay contact in real time in the charging and discharging process or the static state of the main loop, the state of the relay is uploaded to the MUC in real time by adopting the cross type isolation detection technology, the MCU analyzes and processes the state information of the power relay K1 and the power relay K2, and issues a control command in real time according to the system requirement, thereby ensuring the safety and reliability of the main loop system
The system in the charge-discharge circuit control method for detecting whether the contact performances of the power relay K1 and the power relay K2 are normal comprises the following steps:
s1: and (3) charging abnormity control and detection:
at the time of t1, when the system works normally, the power relay K1 and the power relay K2 are in a closed state, and the inverter PCS works normally;
at the time of t2, due to system alarm protection, the power relay K2 is opened, a power relay K1 is normally closed, the inverter PCS is in standby or stopped, during the period, the detection circuit automatically tests the contact state of the power relay K2, the detection result is processed by the data unit and then uploaded to the MCU for analysis and processing, the power relay K2 is normal and closed, the power relay K2 is abnormal, the open state is kept, and manual replacement is carried out;
the power relay K2 is detected to be normal at the moment of t3, the power relay K2 is closed, and the inverter PCS can be started to work normally after time delay according to system requirements;
s2: discharge abnormality control and detection:
at the time of t1, when the system normally works, the power relay K1 and the power relay K2 are in a closed state, and the PCS normally works.
At the time of t2, due to system alarm protection, the power relay K1 acts to be disconnected, the power relay K2 is normally closed, and the PCS is in standby or stopped. Therein, the
In the period, the detection circuit automatically tests the contact state of the power relay K1, the detection result is processed by the data unit and then uploaded to the MCU for analysis and processing, the power relay K1 is normal and closed, and the power relay K1 is abnormal, keeps an open state and is manually replaced;
and (4) detecting that the power relay K1 is normal and closed at the time of t3, and delaying to start the PCS to normally work according to the system requirement.
Main loop power relay K1 and power relay K2 control through MCU, according to the different working methods of main loop, for example charge, discharge and take different control time sequences, carry out disconnection (closure) operation to the relay respectively, when guaranteeing that the relay unilateral keeps good arc extinguishing ability, prevent main loop disconnection (closure) instantaneous peak voltage and the stress of electric current, prevent that the relay contact from oxidizing, gluing.
In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (9)
1. A charge-discharge circuit controlled by double relays is characterized by comprising: the battery charging and discharging main loop and the relay detection control assembly;
the main circuit of the battery charge and discharge consists of a battery pack, a current collector RL, a fuse RF, a power relay K1, a power relay K2, a breaker QF and an inverter PCS which are connected in the circuit;
relay detection control assembly includes that collection circuit, data processing unit, the control unit and MCU are kept apart to the crossing, and the crossing output and the data processing unit that keep apart collection circuit and MCU are connected, and data processing unit output and the control unit connection of electric lines, the output of the control unit and power relay K1, power relay K2's input electric connection.
2. The charging and discharging circuit controlled by the double relays and the control method thereof as claimed in claim 1, wherein the power relay K1 and the power relay K2 are both polar relays, and the inverter PCS is a bidirectional inverter for energy storage.
3. The charge-discharge circuit controlled by two relays and the control method according to claim 1, wherein the cross isolation acquisition circuit is used for acquiring the states of the power relay K1 and the power relay K2 in real time, and the cross isolation acquisition circuit is further used for transmitting the acquired state information to the MCU.
4. The charge-discharge circuit and the control method for controlling the double relays as claimed in claim 1, wherein the MCU is used for analyzing and processing the state information of the relays and issuing control commands in real time according to system requirements;
the MCU adopts an external power supply mode, improves the efficiency of the control circuit and the voltage constraint of power supply of the control chip, is more flexible to apply, reduces interference and improves the reliability of the control circuit.
5. The charge-discharge circuit and the control method for the double-relay control as claimed in claim 1, wherein the data processing unit is configured to receive a control command issued by the MCU, process the control command and transmit the processed control command to the control unit;
the control unit is used for receiving the control signal transmitted by the data processing unit and controlling the opening and closing of the power relay K1 and the power relay K2.
6. A control method of a charge-discharge circuit controlled by double relays is characterized by comprising a relay detection method and a charge-discharge circuit control method.
7. The method for controlling the charge-discharge circuit controlled by the double relays according to claim 6, wherein the relay detection method comprises the following steps:
SS 1: when the relay normally enters the main loop for detection, the power relay K1, the power relay K2 and the breaker QF are all in a closed state;
SS 2: the inverter is in a shutdown or standby state, the system opens the power relay K1, closes the power relay K2, detects Uad voltage and judges whether the power relay K1 is bonded or not according to a detection program;
SS 3: and (3) disconnecting the power relay K2, closing the power relay K1, detecting Ubc voltage, judging whether the power relay K2 is bonded or not, and uploading detection data to the MCU for analysis and processing in real time.
8. The method for controlling the charge-discharge circuit controlled by the double relays according to claim 6, wherein the method for controlling the charge-discharge circuit comprises the following steps:
SS 1: when the main loop is in a charging state and is required to be forcibly disconnected, the power relay K2 must be disconnected according to system definition, the system stops working, a cross type isolation acquisition circuit detects a disconnection signal of the power relay K2, and whether the contact performance after the current power relay K2 acts is normal is detected;
SS 2: when the main loop is in a discharging state and is required to be forcibly disconnected, the power relay K1 needs to be disconnected according to system definition, the system stops working, a cross type isolation acquisition circuit detects a disconnection signal of the power relay K1, and whether the contact performance after the current power relay K1 acts is normal is detected;
SS 3: main loop closing process: according to the requirements of the system, after the power relay K1 and the power relay K2 are normally closed, and the power relay K1 and the power relay K2 are normally detected through the system, the system can normally operate, and the next charging and discharging process is started.
9. The method for controlling the charge and discharge circuit controlled by the double relays as claimed in claim 8, wherein the system for detecting whether the contact performances of the power relay K1 and the power relay K2 are normal in the charge and discharge circuit control method comprises the following steps:
s1: and (3) charging abnormity control and detection:
at the time of t1, when the system works normally, the power relay K1 and the power relay K2 are in a closed state, and the inverter PCS works normally;
at the time of t2, due to system alarm protection, the power relay K2 is opened, a power relay K1 is normally closed, the inverter PCS is in standby or stopped, during the period, the detection circuit automatically tests the contact state of the power relay K2, the detection result is processed by the data unit and then uploaded to the MCU for analysis and processing, the power relay K2 is normal and closed, the power relay K2 is abnormal, the open state is kept, and manual replacement is carried out;
the power relay K2 is detected to be normal at the moment of t3, the power relay K2 is closed, and the inverter PCS can be started to work normally after time delay according to system requirements;
s2: discharge abnormality control and detection:
at the time of t1, when the system normally works, the power relay K1 and the power relay K2 are in a closed state, and the PCS normally works.
At the time of t2, due to system alarm protection, the power relay K1 acts to be disconnected, the power relay K2 is normally closed, and the PCS is in standby or stopped. Therein, the
In the period, the detection circuit automatically tests the contact state of the power relay K1, the detection result is processed by the data unit and then uploaded to the MCU for analysis and processing, the power relay K1 is normal and closed, and the power relay K1 is abnormal, keeps an open state and is manually replaced;
and (4) detecting that the power relay K1 is normal and closed at the time of t3, and delaying to start the PCS to normally work according to the system requirement.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911088959.4A CN110676912A (en) | 2019-11-08 | 2019-11-08 | Charging and discharging circuit controlled by double relays and control method |
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| CN201911088959.4A CN110676912A (en) | 2019-11-08 | 2019-11-08 | Charging and discharging circuit controlled by double relays and control method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111404111A (en) * | 2020-03-16 | 2020-07-10 | 阳光电源股份有限公司 | Driving method and driving circuit of relay |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111404111A (en) * | 2020-03-16 | 2020-07-10 | 阳光电源股份有限公司 | Driving method and driving circuit of relay |
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