Battery PACK simulator

Abstract

The invention discloses a battery PACK simulator which comprises an upper computer, a multi-cell cascade voltage simulation module, a multi-path NTC temperature simulation module and a PACK power simulation module. The multi-cell cascade voltage simulation module outputs the voltage of each cell and realizes an equalization function under the instruction of the upper computer through the MCU controller; the multi-path NTC temperature simulation interface outputs NTC voltages corresponding to different temperatures through the MCU controller under the instruction of the upper computer; and the PACK power interface outputs high-power PACK voltage through the driving control board under the instruction of the upper computer. The system completely simulates a battery PACK, can provide a multi-cell cascade voltage simulation interface, a multi-path NTC temperature simulation interface and a PACK power interface, has the advantages of high safety, low cost, high adjustability of voltage and NTC temperature simulation voltage values and convenience in cell balance test, and greatly improves the debugging and testing efficiency of an energy storage system.

Description

Technical Field

[0001] The invention relates to the technical field of energy storage, in particular to a simulation device of a battery module. Background Art

[0002] With the rapid development of the new energy storage industry, the application of energy storage related products is becoming more and more extensive. Energy storage PCS usually includes battery energy storage system, energy management system and power conversion system; battery energy storage system is responsible for storing electrical energy, energy management system is responsible for monitoring and controlling energy storage and release, and power conversion system is responsible for converting DC power in the battery into AC power or converting AC power into DC power.

[0003] One of the core components of the energy storage system is the battery. In the energy storage industry, multiple single cells are usually connected in series and packaged into a battery module, namely a battery PACK, in order to increase the output voltage.

[0004] During the development of energy storage products, the battery management subsystem BMS must collect the voltage of each single cell in the battery PACK and the multi-channel NTC voltage to conduct a balancing experiment between the cells; the energy management system must also connect the battery PACK power port to perform charge and discharge tests on the battery PACK. Generally, the charge and discharge current is tens of amperes or hundreds of amperes. If a real battery PACK is used for testing, not only will the battery PACK have the disadvantages of being bulky, unsafe, and costly, but the voltage and temperature values ​​are adjusted slowly during the test, and the imbalance simulation effect of the cells is also poor. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a battery PACK simulator with high safety performance and low cost, so as to facilitate the rapid adjustment of voltage and temperature values ​​during testing and test the balanced performance of battery cells, further improve test efficiency and reduce test costs.

[0006] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows.

[0007] A battery PACK simulator comprises a host computer and a multi-cell cascade voltage simulation module, a multi-channel NTC temperature simulation module and a PACK power simulation module which are respectively connected to and communicate with the host computer through wired or wireless means; the output end of the multi-cell cascade voltage simulation module is connected to a multi-cell cascade voltage simulation interface, and the multi-cell cascade voltage simulation module realizes the output of each cell voltage and voltage balance between each cell under the control of an MCU controller according to an instruction of the host computer; the output end of the multi-channel NTC temperature simulation module is connected to a multi-channel NTC temperature simulation interface, and the multi-channel NTC temperature simulation module outputs NTC voltages corresponding to different temperatures under the control of the MCU controller according to an instruction of the host computer; the output end of the PACK power simulation module is connected to the PACK power interface, and the PACK power simulation module outputs the PACK voltage under the control of a drive control board according to an instruction of the host computer.

[0008] Preferably: the multi-cell cascade voltage simulation module includes multiple simulated cells, each simulated cell is respectively connected to the MCU controller and the multi-cell cascade voltage simulation interface, the upper computer sends a cell instruction to the MCU controller, and the MCU controller controls each simulated cell to output the cell voltage to the multi-cell cascade voltage simulation interface.

[0009] Preferably: the negative end of the cell voltage at the simulated cell output end is connected to the positive end of the cell voltage at the previous level simulated cell output end, and the positive end of the cell voltage at the simulated cell output end is connected to the negative end of the cell voltage at the next level simulated cell output end, to achieve cascade simulation of multiple cell voltages.

[0010] Preferably: the analog battery cell includes a signal and power isolation circuit, a digital-to-analog conversion circuit DAC and a conditioning circuit which are electrically connected in sequence, the signal and power isolation circuit is interconnected with the MCU controller, and the output end of the conditioning circuit is connected to a multi-battery cell cascade voltage simulation interface.

[0011] Preferably: the analog battery cell also includes a sampling resistor connected in series between the negative end of the battery voltage at the analog battery cell output end and the multi-battery cell cascade voltage simulation interface, the sampling end of the sampling resistor is connected to the analog-to-digital conversion circuit ADC through a conditioning circuit, and the signal converted by the analog-to-digital conversion circuit ADC is processed by the signal and power isolation circuit and transmitted to the MCU controller.

[0012] Preferably: the multi-channel NTC temperature simulation module includes a multi-channel DAC-NTC simulation circuit; the host computer sends an NTC voltage instruction to the MCU controller, and the multi-channel DAC-NTC simulation circuit outputs a multi-channel NTC voltage to the multi-channel NTC temperature simulation interface under the control of the MCU controller.

[0013] Preferably: the PACK power simulation module is a three-phase bridge topology structure, including a three-phase bridge rectifier inverter circuit composed of three IGBT upper and lower bridge arms, a direct voltage support capacitor and a BUCK-BOOST circuit, the AC side of the three-phase bridge rectifier inverter circuit is connected to the AC power grid, and the DC side of the three-phase bridge rectifier inverter circuit is connected to the PACK power interface via the BUCK-BOOST circuit; the direct voltage support capacitor is connected in parallel to the DC side of the three-phase bridge rectifier inverter circuit; the upper computer sends a PACK port voltage instruction to the drive control board, the drive control board generates an IGBT control signal to control the three-phase bridge rectifier inverter circuit to output a PACK signal, and the PACK signal is filtered by the BUCK-BOOST circuit and output to the PACK power interface.

[0014] Preferably: the PACK power simulation module is a single-phase bridge topology structure, including a single-phase bridge rectifier inverter circuit composed of two IGBT upper and lower bridge arms, a direct voltage support capacitor and a BUCK-BOOST circuit, the AC side of the single-phase bridge rectifier inverter circuit is connected to the AC power grid, and the DC side of the single-phase bridge rectifier inverter circuit is connected to the PACK power interface via the BUCK-BOOST circuit; the direct voltage support capacitor is connected in parallel to the DC side of the single-phase bridge rectifier inverter circuit; the upper computer sends a PACK port voltage instruction to the drive control board, the drive control board generates an IGBT control signal to control the single-phase bridge rectifier inverter circuit to output a PACK signal, and the PACK signal is filtered by the BUCK-BOOST circuit and output to the PACK power interface.

[0015] Due to the adoption of the above technical scheme, the technical progress achieved by the present invention is as follows.

[0016] The present invention completely simulates the battery PACK, and can provide a multi-cell cascade voltage simulation interface, a multi-channel NTC temperature simulation interface and a PACK power interface. The three interfaces can be used separately or in combination as needed. The host computer can control the independent output of the multi-cascade cell voltage and the independent output of the multi-channel NTC temperature simulation voltage. The current of each cell is collected by the module and then uploaded to the host computer. The host computer controls the voltage change of each cell to realize the simulation of the balancing process between cells. The host computer can also control the energy exchange between the PACK power simulation module and the AC power grid to realize the simulated charging and discharging process of the PACK high-power current. The present invention has the advantages of high safety, low cost, strong adjustability of the voltage and NTC temperature simulation voltage values, and convenient cell balancing test, which greatly improves the debugging and testing efficiency of the energy storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural block diagram of the present invention;

[0018] Figure 2It is a schematic diagram of the structure of the multi-cell cascade voltage simulation module and the multi-channel NTC temperature simulation module circuit of the present invention;

[0019] Figure 3 It is a schematic diagram of the circuit structure of the three-phase bridge PACK power simulation module of the present invention;

[0020] Figure 4 It is a circuit structure schematic diagram of the single-phase bridge PACK power simulation module of the present invention. DETAILED DESCRIPTION

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Example 1

[0023] A battery PACK simulator, the structural block diagram of which is as follows Figure 1 As shown, it includes a host computer, an MCU controller, a drive control board, a multi-cell cascade voltage simulation module, a multi-channel NTC temperature simulation module and a PACK power simulation module.

[0024] The multi-cell cascade voltage simulation module and the multi-channel NTC temperature simulation module share the MCU controller and are connected to the MCU controller through control buses, such as Figure 2 As shown; the PACK power simulation module is connected to the drive control board through a control bus, such as Figure 3 As shown; the drive control board and the MCU controller communicate with the host computer through wired or wireless connections, and the wired method can be Ethernet or USB data cable, etc.

[0025] The output end of the multi-cell cascade voltage simulation module is connected to the multi-cell cascade voltage simulation interface. The multi-cell cascade voltage simulation module includes multiple simulated cells, and each simulated cell is connected to the MCU controller and the multi-cell cascade voltage simulation interface respectively.

[0026] The structure of the simulated battery cell is as follows Figure 2 As shown, it includes a signal and power isolation circuit, a digital-to-analog conversion circuit DAC and a conditioning circuit which are electrically connected in sequence. The signal and power isolation circuit is interconnected with the MCU controller, and the output end of the conditioning circuit is connected to a multi-cell cascade voltage analog interface.

[0027] The host computer sends the cell instruction to the MCU controller, and the MCU controller controls the digital-to-analog conversion circuit DAC of each analog cell through the control bus to output the end cell voltage respectively. The end cell voltage is conditioned by the conditioning circuit and output to the multi-cell cascade voltage analog interface.

[0028] A sampling resistor R is connected in series between the negative end of the cell voltage at the analog cell output end and the multi-cell cascade voltage analog interface, and the sampling end of the sampling resistor is connected to the analog-to-digital conversion circuit ADC through a conditioning circuit, and the analog-to-digital conversion circuit ADC is connected to the signal and power isolation circuit. After the terminal voltage signal of the sampling resistor is conditioned by the conditioning circuit, converted by the analog-to-digital conversion circuit ADC, and isolated by the signal and power isolation circuit, it is uploaded to the host computer through the MCU controller, and the host computer adjusts the cell voltage output by each analog cell according to the balanced current between each analog cell and the battery characteristic curve.

[0029] In order to improve the diversity of output voltage in the present invention, each simulated battery cell in the multi-battery cell cascade voltage simulation module can be cascaded, that is: the negative end of the battery cell voltage at the simulated battery cell output end is connected to the positive end of the battery cell voltage at the previous level simulated battery cell output end, and the positive end of the battery cell voltage at the simulated battery cell output end is connected to the negative end of the battery cell voltage at the next level simulated battery cell output end, thereby completing the cascade simulation of multi-battery cell voltages.

[0030] In this embodiment, the multi-cell cascade voltage simulation module includes n simulated cells, such as Figure 2 As shown, the negative terminal GND0 of the cell voltage at the output end of the simulated battery cell 1 serves as the negative terminal of the cascaded battery cell, and the positive terminal of the cell voltage at the output end of the simulated battery cell 1 is connected to the negative terminal GND1 of the cell voltage at the output end of the simulated battery cell 2; the positive terminal of the cell voltage at the output end of the simulated battery cell 2 is connected to the negative terminal GND2 of the cell voltage at the output end of the simulated battery cell 3; and so on; the positive terminal of the cell voltage at the output end of the simulated battery cell n-1 is connected to the negative terminal GNDn-1 of the cell voltage at the output end of the simulated battery cell n, and the positive terminal of the cell voltage at the output end of the simulated battery cell n serves as the positive terminal of the cascaded battery cell to realize multi-cell cascading.

[0031] The simulated cell 1 outputs the cell voltage V0-V1 to the multi-cell cascade voltage simulation interface, the simulated cell 2 outputs the cell voltage V1-V2 to the multi-cell cascade voltage simulation interface, ..., the simulated cell n outputs the cell voltage Vn-1-Vn to the multi-cell cascade voltage simulation interface.

[0032] A sampling resistor R0 is connected in series between the negative end of the cell voltage at the output end of the analog cell 1 and the multi-cell cascade voltage analog interface, and the analog-to-digital conversion circuit ADC of the analog cell 1 collects the voltage between the sampling resistor R0 and the multi-cell cascade voltage analog interface as a basis for calculating the balanced current of the analog cell 1; a sampling resistor R1 is connected in series between the negative end of the cell voltage at the output end of the analog cell 2 and the multi-cell cascade voltage analog interface, and the analog-to-digital conversion circuit ADC of the analog cell 2 collects the voltage between the sampling resistor R1 and the multi-cell cascade voltage analog interface as a basis for calculating the balanced current of the analog cell 2; and so on; a sampling resistor Rn-1 is connected in series between the negative end of the cell voltage at the output end of the analog cell n and the multi-cell cascade voltage analog interface, and the analog-to-digital conversion circuit ADC of the analog cell n collects the voltage between the sampling resistor Rn-1 and the multi-cell cascade voltage analog interface as a basis for calculating the balanced current of the analog cell n.

[0033] The output end of the multi-channel NTC temperature simulation module is connected to the multi-channel NTC temperature simulation interface, and the multi-channel NTC temperature simulation interface outputs NTC voltages corresponding to different temperatures under the instruction of the host computer through the MCU controller.

[0034] The multi-channel NTC temperature simulation module includes a multi-channel DAC-NTC simulation circuit, and the output end of the multi-channel DAC-NTC simulation circuit is connected to the multi-channel NTC temperature simulation interface; the host computer sends an NTC voltage instruction to the MCU controller, and the multi-channel DAC-NTC simulation circuit outputs the multi-channel NTC voltage to the multi-channel NTC temperature simulation interface under the control of the MCU controller. In this embodiment, the multi-channel DAC-NTC simulation circuit can output m NTC voltages N0-Nm, such as Figure 2 shown.

[0035] The PACK power simulation module includes a bridge rectifier inverter circuit, a direct voltage support capacitor, a BUCK-BOOST circuit and a PACK power interface. The PACK power interface outputs the PACK voltage under the command of the host computer through the drive control board.

[0036] In this embodiment, the PACK power simulation module is a three-phase bridge topology structure, such as Figure 3 As shown, it includes a three-phase bridge rectifier inverter circuit composed of three IGBT upper and lower bridge arms IGBT1-IGBT6, a direct voltage support capacitor C1 and a BUCK-BOOST circuit. The AC side of the three-phase bridge rectifier inverter circuit is connected to the AC three-phase power grid, which provides energy exchange during the PACK charge and discharge simulation process; the DC side of the three-phase bridge rectifier inverter circuit is connected to the PACK power interface via the BUCK-BOOST circuit; the direct voltage support capacitor C1 is connected in parallel to the DC side of the three-phase bridge rectifier inverter circuit.

[0037] The BUCK-BOOST circuit includes two transistors IGBT7-IGBT8, an inductor L and a capacitor C2; the controlled end of the transistor IGBT7-IGBT8 is connected to the output end of the drive control board, and the PACK signal output by the three-phase bridge rectifier inverter circuit can be amplified by the control of IGBT7-IGBT8, thereby increasing the adjustable range of the output voltage; the inductor L and the capacitor C2 are used to filter the adjusted output voltage.

[0038] In the present invention, the output end of the PACK power simulation module is also connected in series with a Hall current sensor H to collect the output current. Figure 3 shown.

[0039] The host computer uses the multi-cell cascade voltage as the PACK port voltage instruction. The drive control board generates a three-phase bridge rectifier inverter circuit IGBT drive signal according to the PACK port voltage instruction issued by the host computer, and drives the IGBT to output the instruction voltage. The output current collected by the Hall current sensor H is also uploaded to the host computer through the drive control board. The host computer calculates the battery state of charge SOC based on the output current collected by the Hall current sensor H and the battery characteristic curve, and adjusts the IGBT7-IGBT8 adjustment instruction output to the BUCK-BOOST circuit. Finally, the PACK voltage is output to the PACK power interface after filtering the harmonics. The drive control board collects the PACK power interface terminal voltage as output negative feedback to improve the output accuracy.

[0040] Example 2

[0041] The difference between this embodiment and embodiment 1 is that the PACK power simulation module is a single-phase bridge topology structure, and the single-phase bridge rectifier inverter circuit is composed of two IGBT upper and lower bridge arms, such as Figure 4 shown.

Claims

1. A battery PACK simulator, characterized in that: It includes a host computer and a multi-cell cascade voltage simulation module, a multi-channel NTC temperature simulation module and a PACK power simulation module which are respectively connected to and communicate with the host computer by wire or wirelessly; the output end of the multi-cell cascade voltage simulation module is connected to a multi-cell cascade voltage simulation interface, and the multi-cell cascade voltage simulation module realizes the output of each cell voltage and the voltage balance between each cell under the control of an MCU controller according to the host computer instruction; the output end of the multi-channel NTC temperature simulation module is connected to a multi-channel NTC temperature simulation interface, and the multi-channel NTC temperature simulation module outputs NTC voltages corresponding to different temperatures under the control of the MCU controller according to the host computer instruction; the output end of the PACK power simulation module is connected to a PACK power interface, and the PACK power simulation module outputs the PACK voltage under the control of a drive control board according to the host computer instruction.

2. A battery PACK simulator according to claim 1, characterized in that: The multi-cell cascade voltage simulation module includes multiple simulated cells, each simulated cell is connected to the MCU controller and the multi-cell cascade voltage simulation interface respectively, the upper computer sends a cell instruction to the MCU controller, and the MCU controller controls each simulated cell to output the cell voltage to the multi-cell cascade voltage simulation interface respectively.

3. A battery PACK simulator according to claim 2, characterized in that: The negative end of the cell voltage at the simulated cell output end is connected to the positive end of the cell voltage at the previous level simulated cell output end, and the positive end of the cell voltage at the simulated cell output end is connected to the negative end of the cell voltage at the next level simulated cell output end, thereby realizing cascade simulation of multiple cell voltages.

4. A battery PACK simulator according to claim 2, characterized in that: The analog battery cell includes a signal and power isolation circuit, a digital-to-analog conversion circuit DAC and a conditioning circuit which are electrically connected in sequence. The signal and power isolation circuit is interconnected with the MCU controller, and the output end of the conditioning circuit is connected to a multi-battery cell cascade voltage simulation interface.

5. A battery PACK simulator according to claim 4, characterized in that: The analog cell also includes a sampling resistor connected in series between the negative end of the cell voltage at the analog cell output end and the multi-cell cascade voltage simulation interface. The sampling end of the sampling resistor is connected to the analog-to-digital conversion circuit ADC through a conditioning circuit. The signal converted by the analog-to-digital conversion circuit ADC is processed by the signal and power isolation circuit and then transmitted to the MCU controller.

6. A battery PACK simulator according to claim 1, characterized in that: The multi-channel NTC temperature simulation module includes a multi-channel DAC-NTC simulation circuit; the host computer sends an NTC voltage instruction to the MCU controller, and the multi-channel DAC-NTC simulation circuit outputs a multi-channel NTC voltage to the multi-channel NTC temperature simulation interface under the control of the MCU controller.

7. A battery PACK simulator according to claim 1, characterized in that: The PACK power simulation module is a three-phase bridge topology structure, including a three-phase bridge rectifier inverter circuit composed of three IGBT upper and lower bridge arms, a direct voltage support capacitor and a BUCK-BOOST circuit. The AC side of the three-phase bridge rectifier inverter circuit is connected to the AC power grid, and the DC side of the three-phase bridge rectifier inverter circuit is connected to the PACK power interface via the BUCK-BOOST circuit; the direct voltage support capacitor is connected in parallel to the DC side of the three-phase bridge rectifier inverter circuit; the upper computer sends a PACK port voltage instruction to the drive control board, and the drive control board generates an IGBT control signal to control the three-phase bridge rectifier inverter circuit to output a PACK signal, and the PACK signal is filtered by the BUCK-BOOST circuit and output to the PACK power interface.

8. A battery PACK simulator according to claim 1, characterized in that: The PACK power simulation module is a single-phase bridge topology structure, including a single-phase bridge rectifier inverter circuit composed of two IGBT upper and lower bridge arms, a direct voltage support capacitor and a BUCK-BOOST circuit. The AC side of the single-phase bridge rectifier inverter circuit is connected to the AC power grid, and the DC side of the single-phase bridge rectifier inverter circuit is connected to the PACK power interface via the BUCK-BOOST circuit; the direct voltage support capacitor is connected in parallel to the DC side of the single-phase bridge rectifier inverter circuit; the upper computer sends a PACK port voltage instruction to the drive control board, and the drive control board generates an IGBT control signal to control the single-phase bridge rectifier inverter circuit to output a PACK signal, and the PACK signal is filtered by the BUCK-BOOST circuit and output to the PACK power interface.

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