A new energy vehicle battery management system

Abstract

The present invention discloses a new energy vehicle battery management system, which belongs to the technical field of new energy vehicles. The system includes: a single pack main controller: used for performing a primary power estimation and fault detection on a single battery pack according to single cell data and single battery pack data, and obtaining a primary power estimation value and fault detection result of a single battery pack; a total main controller: used for performing a secondary power estimation on a single battery pack according to single cell data and single battery pack data, and obtaining a secondary power estimation value of a single battery pack; performing power estimation on all battery packs according to the total data of all battery packs, and obtaining power estimation values ​​of all battery packs; performing a double check on the primary power estimation value of a single battery pack according to the secondary power estimation value of a single battery pack and the power estimation values ​​of all battery packs. The system is applicable to a variety of battery packs, can solve the problems of difficult troubleshooting and long maintenance cycle, and can improve the accuracy of power estimation.

Description

Technical Field

[0001] The invention relates to a new energy vehicle battery management system, belonging to the technical field of new energy vehicles. Background Art

[0002] The Battery Management System (BMS) is the brain of the electric vehicle's power battery, responsible for monitoring and managing the working status of the battery pack.

[0003] BMS collects, processes, and stores important information during the operation of the battery pack, such as voltage, current, temperature, etc., in real time to ensure that the battery pack operates within a safe and efficient range. BMS can also prevent the battery from overcharging or over-discharging, ensuring the safety and life of electric vehicles.

[0004] The current mainstream battery management system master-slave architecture is applicable to a relatively single battery pack product, making troubleshooting difficult, with a long maintenance cycle, and lacking full life cycle battery data information monitoring. Overall, it lacks applicability to a variety of battery pack products and the ability to remotely monitor upgrades and adjustments. Summary of the invention

[0005] The purpose of the present invention is to provide a new energy vehicle battery management system that is applicable to a variety of battery packs, can solve the problems of difficult troubleshooting and long maintenance cycle, and can improve the accuracy of power estimation.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention provides a new energy vehicle battery management system, wherein the new energy vehicle battery includes a plurality of battery packs, each battery pack includes a plurality of single cells, and the system includes:

[0008] Single cell data collection controller: used to collect single cell battery data;

[0009] Single-pack acquisition controller: used to collect data of a single battery pack;

[0010] Single pack main controller: used to estimate the power of a single battery pack and detect faults based on the data of the single battery and the single battery pack, and obtain the power estimation value and fault detection result of the single battery pack;

[0011] Single-pack remote transmission controller: used to transmit single-cell battery data, single battery pack data, and single battery pack power estimation value and fault detection results to the background for storage;

[0012] Total acquisition controller: used to collect total data of all battery packs;

[0013] The main controller is used to perform a secondary estimation of the power of a single battery pack based on the data of the single battery cell and the data of a single battery pack, and obtain the secondary estimation value of the power of the single battery pack; perform a power estimation of all battery packs based on the total data of all battery packs, and obtain the estimated power values ​​of all battery packs; perform a double check on the primary estimation value of the power of a single battery pack based on the secondary estimation value of the power of a single battery pack and the estimated power values ​​of all battery packs;

[0014] Total remote transmission controller: used to transmit the total data of all battery packs, the secondary estimated value of the power of a single battery pack, and the estimated value of the power of all battery packs to the background for storage.

[0015] Furthermore, the controllers are communicatively connected via a controller area network bus.

[0016] Furthermore, the single cell data includes the voltage and temperature of the single cell; the single battery pack data includes the high voltage voltage, current, and insulation resistance value of the single battery pack; and the total data of all battery packs includes the total high voltage voltage, total current, and total insulation resistance value of all battery packs.

[0017] Furthermore, the single cell acquisition controller performs voltage acquisition and balancing control on the single cell through the first preset chip to obtain the voltage of the single cell, and performs temperature acquisition on the single cell by connecting the temperature sensor through the first preset chip to obtain the temperature of the single cell;

[0018] Wherein, the first preset chip is an AFE chip.

[0019] Furthermore, the single-pack acquisition controller collects high-voltage voltage, current, and insulation resistance values ​​of a single battery pack through a second preset chip to obtain the high-voltage voltage, current, and insulation resistance values ​​of the single battery pack;

[0020] Wherein, the second preset chip is the MC33772C chip.

[0021] Furthermore, the total acquisition controller acquires the total high voltage voltage and total insulation resistance value of all battery packs by collecting the high voltage voltage and insulation resistance value of the main lines connecting all battery packs, and acquires the branch current of each battery pack by collecting the current of the branch lines connecting each battery pack through the Hall current sensor provided in each battery pack, and acquires the branch current of each battery pack, and acquires the total current of all battery packs by adding the branch currents of each battery pack.

[0022] Furthermore, the single-pack main controller uses the third preset chip as the central processor and the fourth preset chip as the battery management chip, and processes the single cell data and single battery pack data through the third preset chip and the fourth preset chip to obtain a single battery pack power estimate and fault detection results.

[0023] Furthermore, the single-packet main controller wakes up the fourth preset chip through the fifth preset chip to perform battery management.

[0024] Further, the fault detection includes sensor fault detection, network fault detection, battery overcharge / overdischarge / overcurrent detection, and insulation fault detection;

[0025] The sensors include a temperature sensor in the single-cell acquisition controller for acquiring the temperature of a single cell, a shunt in the single-pack acquisition controller for acquiring the current of a single battery pack, and a Hall current sensor in the total acquisition controller for acquiring the branch current of each battery pack;

[0026] The network failure includes a daisy chain communication connection failure between chips in each of the controllers and a controller area network bus communication connection failure between each of the controllers.

[0027] Furthermore, the main controller uses the third preset chip as the central processing unit and the fourth preset chip as the battery management chip, and processes the single cell data, the single battery pack data, and the total data of all battery packs through the third preset chip and the fourth preset chip to obtain the secondary estimated value of the power of a single battery pack and the estimated value of the power of all battery packs, and based on the secondary estimated value of the power of a single battery pack and the estimated value of the power of all battery packs, double-check the primary estimated value of the power of a single battery pack.

[0028] Furthermore, the overall main controller wakes up the fourth preset chip through the fifth preset chip to perform battery management.

[0029] Furthermore, the main controller exchanges information with the charging pile to determine the access status of the charging gun. When the charging gun is connected, it sends the currently required charging current and charging voltage to the charging pile, receives the current charging current and charging voltage fed back by the charging pile, and performs fault diagnosis on the charging faults generated during the charging process, and sends an alarm prompt to the entire vehicle based on the fault diagnosis results.

[0030] Furthermore, the overall main controller sends a high-voltage power-on control signal or a high-voltage power-off control signal to the single-package main controller according to the fault detection result, and the single-package main controller controls the main positive contactor and the main negative contactor to close according to the high-voltage power-on control signal to supply high voltage, or controls the main positive contactor and the main negative contactor to open according to the high-voltage power-off control signal to cut off high voltage power.

[0031] Furthermore, the main controller sends a heat dissipation signal to the vehicle multi-source thermal management system based on the temperature of the single cell collected by the single cell collection controller, and the vehicle multi-source thermal management system dissipates heat based on the heat dissipation signal; wherein the heat dissipation signal includes an enable signal and a preset temperature signal.

[0032] Furthermore, the third preset chip is a TC387 chip, and the fourth preset chip is a TLF35584 chip.

[0033] Furthermore, the fifth preset chip is an RTC chip.

[0034] Furthermore, the single-package main controller and the master main controller can remotely upgrade the software through over-the-air download technology and mobile network communication, and both have software backup, software AB partitioning, and software rollback functions.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The new energy vehicle battery management system provided by the present invention is a single-pack master controller that performs a primary power estimation and fault detection on a single battery pack based on the data of the single cell and the data of a single battery pack. The three-level architecture of the master master-single-pack master-slave controller is formed by the master master controller, the single-pack master controller and each acquisition controller. Single-pack battery management can be performed without a master controller, and multiple different forms of battery packs can be compatible without changing the hardware, solving the problems of the existing master-slave architecture that is applicable to a single battery pack, difficult fault troubleshooting, and a long maintenance cycle, and improving the versatility of the battery management system. The single-pack master controller performs a primary power estimation on a single battery pack, the master master controller performs a secondary power estimation on a single battery pack, and the power estimation is performed on all battery packs. The primary power estimation value of a single battery pack is double-checked based on the secondary power estimation value of a single battery pack and the power estimation values ​​of all battery packs, which can improve the accuracy of power estimation. Through the single-pack remote transmission controller and the total remote transmission controller, data transmission of a single battery pack and all battery packs can be achieved simultaneously. The single-cell data, single battery pack data, primary estimated value of power of a single battery pack, secondary estimated value of power, fault detection results and total data of all battery packs, and estimated value of power of all battery packs are transmitted to the background for storage, which makes it easy to query the historical data of a single battery pack and all battery packs, and realize full life cycle battery data information monitoring.

[0037] The new energy vehicle battery management system provided by the present invention, the chips used by the single-cell acquisition controller and the single-package acquisition controller have an automatic addressing function, the single-package master controller and the total master controller have corresponding addressing interfaces, can automatically address multiple slave controllers, number multiple slave controllers, and distinguish the information fed back by each slave controller.

[0038] The new energy vehicle battery management system provided by the present invention, the single-pack main controller and the total main controller can remotely upgrade the software through the over-the-air download technology and mobile network communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is an electrical schematic diagram of a single-pack battery management system provided by an embodiment of the present invention;

[0040] Figure 2 is an electrical schematic diagram of a multi-pack battery management system provided by an embodiment of the present invention;

[0041] Figure 3 It is a schematic diagram of the information flow of SRDB and MRDB data transmission provided by an embodiment of the present invention;

[0042] Figure 4 is a schematic diagram of the functional architecture of a CSC system provided by an embodiment of the present invention;

[0043] Figure 5 is a schematic diagram of the functional architecture of a CVS system provided by an embodiment of the present invention;

[0044] Figure 6 is a schematic diagram of the functional architecture of the SBMU system provided by an embodiment of the present invention;

[0045] Figure 7 is a schematic diagram of the functional architecture of an MBMU system provided by an embodiment of the present invention;

[0046] Figure 8 is a schematic diagram of a circuit for connecting an AFE chip pin and a temperature sensor provided by an embodiment of the present invention;

[0047] Fig. 9 is a schematic diagram of a high voltage acquisition circuit provided by an embodiment of the present invention, wherein (a) represents a positive high voltage acquisition circuit, and (b) represents a bipolar high voltage acquisition circuit;

[0048] Fig.10 is a schematic diagram of a current collection circuit provided by an embodiment of the present invention;

[0049] Fig.11 is a schematic diagram of an insulation resistance detection circuit provided by an embodiment of the present invention;

[0050] Fig.12 is a schematic diagram of an equivalent circuit for the first measurement of insulation resistance provided by an embodiment of the present invention;

[0051] Fig.13 It is a schematic diagram of an equivalent circuit for the second measurement of insulation resistance provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0052] The technical solution of the present application is further described in detail below in conjunction with specific implementation methods.

[0053] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as limitations on the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments may be combined with each other.

[0054] Embodiment 1:

[0055] This embodiment provides a new energy vehicle battery management system. The new energy vehicle battery includes a plurality of battery packs, each battery pack includes a plurality of single cells, and the system includes:

[0056] Single cell data collection controller: used to collect single cell battery data;

[0057] Single-pack acquisition controller: used to collect data of a single battery pack;

[0058] Single pack main controller: used to estimate the power of a single battery pack and detect faults based on the data of the single battery and the single battery pack, and obtain the power estimation value and fault detection result of the single battery pack;

[0059] Single-pack remote transmission controller: used to transmit single-cell battery data, single battery pack data, and single battery pack power estimation value and fault detection results to the background for storage;

[0060] Total acquisition controller: used to collect total data of all battery packs;

[0061] The main controller is used to perform a secondary estimation of the power of a single battery pack based on the data of the single battery cell and the data of a single battery pack, and obtain the secondary estimation value of the power of the single battery pack; perform a power estimation of all battery packs based on the total data of all battery packs, and obtain the estimated power values ​​of all battery packs; perform a double check on the primary estimation value of the power of a single battery pack based on the secondary estimation value of the power of a single battery pack and the estimated power values ​​of all battery packs;

[0062] Total remote transmission controller: used to transmit the total data of all battery packs, the secondary estimated value of the power of a single battery pack, and the estimated value of the power of all battery packs to the background for storage.

[0063] In this embodiment, the controllers are connected to each other through a controller area network bus.

[0064] The single cell data includes the voltage and temperature of the single cell; the single battery pack data includes the high voltage voltage, current, and insulation resistance value of the single battery pack; the total data of all battery packs includes the total high voltage voltage, total current, and total insulation resistance value of all battery packs.

[0065] The single cell acquisition controller acquires the voltage of the single cell and performs equalization control on the single cell through the first preset chip to obtain the voltage of the single cell, and acquires the temperature of the single cell by connecting the temperature sensor to the single cell through the first preset chip to obtain the temperature of the single cell.

[0066] In other possible embodiments, the first preset chip is an AFE chip.

[0067] The single-pack acquisition controller collects high-voltage voltage, current, and insulation resistance values ​​of a single battery pack through a second preset chip to obtain the high-voltage voltage, current, and insulation resistance values ​​of the single battery pack.

[0068] In other possible embodiments, the second preset chip is a MC33772C chip.

[0069] The total acquisition controller acquires the total high voltage voltage and total insulation resistance value of all battery packs by collecting the high voltage voltage and insulation resistance value of the main lines connecting all battery packs, and acquires the branch current of each battery pack by collecting the current of the branch lines connecting each battery pack through the Hall current sensor provided in each battery pack. The branch current of each battery pack is added together to acquire the total current of all battery packs.

[0070] The single-pack main controller uses the third preset chip as the central processor and the fourth preset chip as the battery management chip. The third preset chip and the fourth preset chip process the single cell data and the single battery pack data to obtain a single battery pack power estimate and fault detection results.

[0071] Fault detection includes sensor fault detection, network fault detection, battery overcharge / overdischarge / overcurrent detection, and insulation fault detection.

[0072] The sensors include a temperature sensor in a single cell acquisition controller for acquiring the temperature of a single cell, a shunt in a single pack acquisition controller for acquiring the current of a single battery pack, and a Hall current sensor in a total acquisition controller for acquiring the branch current of each battery pack.

[0073] Network failures include daisy chain communication connection failures between chips in each controller and controller area network bus communication connection failures between controllers.

[0074] In other possible embodiments, the single-packet main controller wakes up the fourth preset chip through the fifth preset chip to perform battery management.

[0075] The main controller uses the third preset chip as the central processing unit and the fourth preset chip as the battery management chip. The third preset chip and the fourth preset chip are used to process the single cell data, the single battery pack data, and the total data of all battery packs to obtain the secondary estimated value of the power of a single battery pack and the estimated value of the power of all battery packs. Based on the secondary estimated value of the power of a single battery pack and the estimated value of the power of all battery packs, a double check is performed on the primary estimated value of the power of a single battery pack.

[0076] The main controller exchanges information with the charging pile to determine the access status of the charging gun. When the charging gun is connected, it sends the currently required charging current and charging voltage to the charging pile, receives the current charging current and charging voltage fed back by the charging pile, and diagnoses the charging faults generated during the charging process, and sends an alarm prompt to the entire vehicle based on the fault diagnosis results.

[0077] The main controller sends a high-voltage power-on control signal or a high-voltage power-off control signal to the single-package main controller according to the fault detection result, and the single-package main controller controls the main positive contactor and the main negative contactor to close and supply high voltage power according to the high-voltage power-on control signal, or controls the main positive contactor and the main negative contactor to disconnect and disconnect the high voltage according to the high-voltage power-off control signal. The high-voltage power-on control signal and the high-voltage power-off control signal are signals used to control the on and off of the high-voltage power supply. The high-voltage power-on control signal is a signal used to close the high-voltage power supply control loop. When the high-voltage power-on control signal is received, the related high-voltage electrical components (such as relays, contactors, etc.) will close, so that the high-voltage power supply is turned on, and the high-voltage power-on operation is realized, and the high-voltage power supply is provided to the system. The high-voltage power-off control signal is a signal used to disconnect the high-voltage power supply control loop. When the high-voltage power-off control signal is received, the related high-voltage electrical components (such as relays, contactors, etc.) will disconnect, so that the high-voltage power supply is disconnected, and the high-voltage power-off operation is realized, and the high-voltage power supply of the system is cut off.

[0078] The main controller sends a heat dissipation signal to the vehicle multi-source thermal management system based on the temperature of the single battery collected by the single battery collection controller, and the vehicle multi-source thermal management system dissipates heat based on the heat dissipation signal; wherein the heat dissipation signal includes an enable signal and a preset temperature signal.

[0079] In other possible embodiments, the main main controller wakes up the fourth preset chip through the fifth preset chip to perform battery management.

[0080] In other possible embodiments, the third preset chip is a TC387 chip, and the fourth preset chip is a TLF35584 chip.

[0081] In other possible embodiments, the fifth preset chip is an RTC chip.

[0082] In other possible embodiments, the single-package main controller and the master main controller both remotely upgrade the software through Over-the-Air Technology (OTA) and mobile network communication, and both have software backup, software AB partitioning, and software rollback functions.

[0083] Embodiment 2:

[0084] This embodiment provides a new energy vehicle battery management system, which is applied to a single battery pack, such as Figure 1 As shown in the figure, it includes the main master controller MBMU, the main acquisition controller MHVB, the main remote transmission controller MRDB, the single packet master controller SBMU, the single packet acquisition controller CVS, the single acquisition controller CSC, and the single packet remote transmission controller SRDB. The controllers are connected through the controller area network bus CAN communication to ensure the stability of information exchange between the controllers and form a stable CAN network. Figure 1 As shown, MBMU is connected to charging CAN, debugging CAN, vehicle CAN and master-slave CAN respectively. Figure 1 In the figure, HV+ and HV- represent the high voltage positive electrode and the high voltage negative electrode, I / O&AD represents input / output & analog-to-digital conversion, H / LSD represents high-side and low-side drive output, C1 and Cn represent battery cells, MSD represents maintenance switch, V&T represents single cell voltage & battery temperature, PDM represents power management module, KL30 and KL31 represent the low voltage power supply positive electrode and the low voltage power supply negative electrode, and Power represents CVS low voltage power supply.

[0085] This embodiment provides a new energy vehicle battery management system, which is applied to multiple battery packs. For example, three battery packs are used. Figure 2 As shown, the battery pack 1 and Figure 1 The internal structure of the battery packs is the same, and the internal structure of battery packs 2 and 3 is the same as that of battery pack 1. The controllers of each battery pack are connected through the controller area network bus CAN communication to ensure the stability of information exchange between the controllers and form a stable CAN network. Figure 2 In the figure, HV+ and HV- represent the high voltage positive electrode and the high voltage negative electrode, I / O&AD represents input / output & analog-to-digital conversion, H / LSD represents high-side and low-side drive output, C1 and Cn represent battery cells, MSD represents maintenance switch, V&T represents single cell voltage & battery temperature, PDM represents power management module, KL30 and KL31 represent the low voltage power supply positive electrode and the low voltage power supply negative electrode, and Power represents CVS low voltage power supply.

[0086] In this embodiment, the new energy vehicle has three battery packs, each of which contains 250 single cells.

[0087] like Figure 2 As shown, there is one SBMU in each battery pack, and three SBMUs are connected to the MBMU via CAN communication.

[0088] There is one CVS in each battery pack, and the CVS communicates with the SBMU via the CAN in the single pack.

[0089] There are 4 CSCs in each battery pack, and the 4 CSCs are connected to the SBMU through the CAN in a single pack.

[0090] There is one SRDB in each battery pack, and the SRDB communicates with the SBMU via the CAN in the single pack.

[0091] MBMU communicates and interacts with the battery management system host computer through a single CAN channel, which can calibrate, control, record and analyze the battery status, and can also be used for offline detection control.

[0092] MBMU collects and manages the data of total battery voltage, total current, cell voltage, cell temperature, insulation resistance value, collision status, and smoke status, and then estimates the battery power SOC and battery health status SOH based on the corresponding data, and detects sensor failure, network failure, battery failure, battery overcharge / overdischarge / overcurrent, and insulation failure online, and performs charging control, high-voltage power-on and power-off control, and thermal management control. MBMU is the information processing and control core of the entire battery management system and the brain of the entire battery management system. High-voltage power-on and power-off control refers to controlling the on and off of the high-voltage power supply. High-voltage power-on control refers to controlling the closing of related high-voltage electrical components (such as relays, contactors, etc.) to turn on the high-voltage power supply, realize high-voltage power-on operation, and provide high-voltage power supply for the system. High-voltage power-off control refers to controlling the disconnection of related high-voltage electrical components (such as relays, contactors, etc.) to disconnect the high-voltage power supply, realize high-voltage power-off operation, and cut off the high-voltage power supply of the system.

[0093] MHVB collects the total voltage and current of each battery pack, performs insulation detection on the high voltage, and sends the voltage value, current value, and insulation resistance value to MBMU via CAN, which determines the status.

[0094] MBMU sends the battery data and status to MRDB via CAN. MRDB transmits the battery data and status to the background through the mobile communication network for data monitoring and storage. It remotely monitors the battery pack status of each vehicle in real time, understands the battery working status, and can retrieve historical records. For battery failures, data analysis can be performed based on historical records to help find the root cause of the failure.

[0095] As the master controller of a single battery pack, SBMU can control the high-voltage output of the battery pack, estimate the SOC of a single battery, collect the single cell voltage temperature, the total current, high-voltage voltage, and insulation resistance value data of a single battery pack, and send the data to MBMU via CAN. The two controllers MBMU and SBMU verify each other to improve the accuracy of power estimation.

[0096] CVS collects the high voltage, total current, and insulation resistance value of a single battery pack and sends the data to the SBMU via CAN communication within the single pack.

[0097] The CSC collects temperature and voltage data and performs balancing control on the battery cells in the battery pack, and sends the data to the SBMU via the CAN in the single pack.

[0098] SBMU sends the battery data and status to SRDB via CAN, and SRDB transmits the battery data and status to the background through the mobile communication network for data monitoring and storage.

[0099] As a remote data bridge, SRDB's main function is to transmit the battery information of BMS to the background data center.

[0100] The information flow of SRDB and MRDB data transmission is as follows Figure 3 As shown, SRDB and MRDB are connected to routers via code division multiple access (CDMA) and the Internet to transmit battery information to a monitoring station, a program service station or perform data analysis.

[0101] like Figure 4 As shown, the CSC board uses the AFE chip MC33774 to collect single cell voltage, single cell temperature, and single cell balancing control. Four AFE chips are used on one board, and one AFE chip can collect 18 single cell voltages and 9 single cell temperatures. Daisy chain communication is used between the AFE chips. The battery management communication gateway and the transformer physical layer (TPL) transceiver MC33665A are used to convert the TPL signal into a CAN signal. The MC33774 and MC33665A are isolated from each other through a network transformer. Four CSC boards are used in one battery pack, and the boards interact with each other through CAN communication. The boards retain the function of interacting through daisy chain signals. The CSC board can interact using both CAN and daisy chain methods to meet the needs of products with different working conditions and different cost requirements, and has the function of automatic addressing of multiple CSCs.

[0102] The circuit connecting the AFE chip pin and the temperature sensor is as follows Figure 8 shown. Figure 8In the figure, NTC indicates the connected temperature sensor, GPIO indicates the connected AFE chip pin, VA1 indicates ground, VAUX indicates power supply, D1 indicates clamping diode, R1 indicates voltage divider resistor, R2 indicates current limiting resistor, and C1 and C2 indicate filter capacitors.

[0103] The storage value in SECM_APP_AINx of the temperature sensor is A, 0.154 is the conversion coefficient of MC33774, the input voltage value is VGPIO, the power supply voltage is VVAUX, the temperature sensor resistance is Rt, VGPIO=A×0.154mV, Rt=VGPIO×R1 / (VVAUX-VGPIO), and then according to the RT table of the temperature sensor, find the temperature value corresponding to the Rt value.

[0104] like Figure 5 As shown, CVS uses MC33772C chip. Each MC33772C can collect 1 shunt current and 7 high-voltage inputs, and has the function of insulation resistance value detection. Each board has 3 MC3377Cs, which can collect 21 channels of high-voltage voltage. The board power uses DCDC isolated power supply to convert the low-voltage power supply 12V into high-voltage power supply 12V to ensure that the low-voltage power supply is isolated from the high-voltage power supply. The low-voltage 12V power supply supplies power to MC33665A, and the isolated high-voltage 12V power supply supplies power to MC33772C. The board sends the collected high-voltage voltage, high-voltage current and insulation resistance value to SBMU through CAN communication.

[0105] The MC33772C chip (6-channel lithium-ion battery controller IC) includes multiple functions: high voltage acquisition, current acquisition, insulation resistance detection, etc. This embodiment introduces in detail the calculation standards for the data results generated by the three functions.

[0106] 1. High voltage collection:

[0107] like Figure 5 As shown, CVS is provided with 8 high voltage acquisition channels, of which 6 are positive high voltage acquisition channels. The positive high voltage acquisition circuit is shown in Fig. 9 As shown in (a), 2 channels are bipolar high voltage acquisition. The bipolar high voltage acquisition circuit is as follows: Fig. 9 As shown in (b).

[0108] SW: High-voltage switch. In order to reduce the leakage current in the resistor without measurement, SW can disconnect the bridge to ensure that the BMS does not collect high voltage at the same time as other devices (such as charging piles) to eliminate safety hazards. Fig. 9 As shown, SW is controlled by MC33772C digital output and level converter.

[0109] : bridge. The high voltage is gradually attenuated to the input voltage range of MC33772C. The resistor needs to meet the requirements of high resistance, high precision and high power. Fig. 9 Five resistors with a resistance value of 402kΩ, an accuracy of 0.1%, and a power of 1 / 3W are connected in series. .

[0110] : Sampling resistor. Voltage divider value As the collected data, it is transmitted to MC33772C. There are two cases: ① Positive high voltage collection. Fig. 9 Middle (a) Middle Select a resistor with a resistance value of 10kΩ, an accuracy of 1%, and a power of 1 / 10W. ② Bipolar high voltage acquisition. Fig. 9 Middle (b) Middle A resistor with a resistance value of 5.1kΩ, an accuracy of 1%, and a power of 1 / 10W is selected.

[0111] :Current limiting resistor. There are two cases: ① Positive high voltage collection. Fig. 9 Middle (a) Middle The resistor with a resistance value of 2.7kΩ, an accuracy of 1%, and a power of 1 / 10W is selected. ② Bipolar high voltage acquisition. Fig. 9 Middle (b) Middle Select a resistor with a resistance value of 1.8kΩ, an accuracy of 1%, and a power of 1 / 10W.

[0112] :Filter capacitor. There are two cases: ① Positive high voltage collection. Fig. 9 Middle (a) Middle Select a capacitor with a capacitance value of 22nF, an accuracy of 10%, and a rated voltage of 50V. ② Bipolar high voltage acquisition. Fig. 9 Middle (b) Middle A capacitor with a capacitance value of 47nF, an accuracy of 10%, and a rated voltage of 50V is selected.

[0113] : Voltage reference in bipolar high voltage acquisition. Fig. 9 Middle (b) Middle is 2.5V.

[0114] Positive high voltage acquisition range: 0V~+1000V.

[0115] Bipolar high voltage acquisition range: -1000V~+1000V.

[0116] The limit value for SW to close is -1500V~+1500V.

[0117] Voltage measurement stabilization time: 5ms.

[0118] In order to unify the formula for positive high voltage acquisition and bipolar high voltage acquisition, it is assumed that Fig. 9 In (a), there is a voltage equivalent to 0V. .

[0119] In the MC33772C chip manual: After voltage measurement, the MC33772C returns a 15-bit signed value, which is stored in the MEAS_ANx or MEAS_CT1 register, depending on the channel. After voltage measurement, the MC33772C converter returns a 15-bit signed value, which is stored in the MEAS_ANx or MEAS_CT1 register depending on the channel. This conversion method allows the MC33772C to handle high voltage measurements, ensuring the accuracy and reliability of the measurements. In this way, voltage measurement data in high voltage systems can be effectively managed and controlled, thereby supporting the needs for high voltage measurements in various applications.

[0120] Right now , the specific formula is derived as follows:

[0121] ① Positive high voltage collection:

[0122] ;

[0123] .

[0124] ② Bipolar high voltage acquisition:

[0125] ;

[0126] ;

[0127] ;

[0128] ;

[0129] ;

[0130] ;

[0131] in, Indicates the input voltage of MC33772C after the high voltage acquisition channel. It indicates the high voltage acquisition result obtained through calculation based on the high voltage acquisition data.

[0132] The specification constraints are shown in Table 1.

[0133] Table 1 Voltage conversion parameters

[0134] .

[0135] 2. Current collection:

[0136] like Fig.10 As shown, using a shunt Connect in series after the last single cell of the high-voltage battery pack and before the negative electrode of the high-voltage battery pack, using a small resistance resistor Convert the total current of the battery pack into a voltage value within an appropriate range for measurement. Fig.10 In the figure, CELL1 and CELL2 represent single cells. , , , , , Represents the filter capacitor, , , Represents the current limiting resistor, Indicates anti-static diode, , Indicates the balancing resistor, CT_1, CB_1, CT_2, CB_2, CB_2:1_C, CT_REF, ISENSE+, ISENSE-, AGND are the MC33772C chip pins, , It is a balanced field effect transistor integrated inside the MC33772C chip.

[0137] The symbol meaning and value range of current acquisition are shown in Table 2.

[0138] Table 2 Symbols and value ranges for current acquisition

[0139] .

[0140] The specific formula is derived as follows:

[0141] ;

[0142] Right now:

[0143] ;

[0144] in, It indicates the current collection result obtained by calculation based on the current collection data. It represents the collected data of the analog-to-digital converter ADC of MC33772C. Indicates the accuracy of the current measurement ADC.

[0145] 3. Insulation resistance detection:

[0146] Insulation resistance detection circuit Fig.11 As shown, Fig.11 In the embodiment, the vehicle chassis is grounded, SW1, SW2, and SW3 represent a first high voltage switch, a second high voltage switch, and a third high voltage switch. The present application improves the existing insulation resistance detection steps, and the improved insulation resistance detection steps are shown in Table 3.

[0147] Table 3 Improved insulation resistance test steps

[0148] .

[0149] The symbol meaning and value range of insulation resistance detection are shown in Table 4.

[0150] Table 4 Symbols and value ranges for insulation resistance testing

[0151] .

[0152] : Total voltage of battery pack PACK.

[0153] :first value.

[0154] : Second time value.

[0155] :Right now , insulation resistance of the upper half bridge.

[0156] :Right now , insulation resistance of the lower half bridge.

[0157] ‌MC33772C chip manual:

[0158] The formula for the insulation resistance to vary with the measured value is:

[0159] ;

[0160] in, , Represents the conductivity of the insulation resistance of the upper and lower half bridges, , , , Represents resistance , , , Conductivity.

[0161] The first measurement equivalent circuit is as follows Fig.12 As shown:

[0162] (1);

[0163] (2);

[0164] (3);

[0165] Substituting formula (2) and formula (3) into formula (1), we get:

[0166] (4);

[0167] in, , Represents the upper and lower half bridge voltages, , Represents the upper and lower half-bridge resistances, represents the measured resistance, Represents the half-bridge current.

[0168] The equivalent circuit of the second measurement is as follows Fig.13 As shown:

[0169] (5);

[0170] (6);

[0171] (7);

[0172] Substituting formula (6) and formula (7) into formula (5), we get:

[0173] (8);

[0174] Simplifying formula (4) and formula (8), we get:

[0175] (9);

[0176] (10);

[0177] Transforming equations (9) and (10) into conductance, we obtain:

[0178] (11);

[0179] (12);

[0180] Dividing formula (11) by formula (12), we get:

[0181] ;

[0182] in, , Indicates the conductance corresponding to the insulation resistance of the upper and lower half bridges.

[0183] Set the intermediate variable , , simplifying to get:

[0184] ;

[0185] ;

[0186] ;

[0187] ;

[0188] ;

[0189] ;

[0190] ;

[0191] ;

[0192] Substitution , ,get:

[0193] ;

[0194] ;

[0195] By simplifying formula (11), we can get:

[0196] ;

[0197] ;

[0198] ;

[0199] ;

[0200] Substitution ,get:

[0201] ;

[0202] ;

[0203] ;

[0204] ;

[0205] ;

[0206] ;

[0207] ;

[0208] ;

[0209] .

[0210] Fig.12 , Fig.13 In the text, Chassis refers to the chassis of the vehicle.

[0211] Compare to the MC33772C chip manual:

[0212] The formula for the insulation resistance to vary with the measured value is:

[0213] .

[0214] The only difference is the manual , this standard , second measurement, parallel resistance , total battery voltage unchanged, the lower half bridge voltage Reduce, and The voltage division ratio of the series part remains unchanged, which eventually results in Must be less than .

[0215] The specification constraints are shown in Table 5.

[0216] Table 5 Isolation measurement conversion parameters

[0217] .

[0218] like Figure 6 As shown, SBMU uses Infineon TC387 chip as the core CPU, TLF35584 chip as the board power management chip, and RTC chip PCF8563 with wake-up function, which can wake up the controller regularly for battery management. It has multiple digital input, digital output, analog input channels, charging detection port, 4-way CAN communication, and high-voltage interlocking function. SBMU can independently perform single-pack battery management, SOC estimation, and high-voltage power-on and power-off control, and send information to MBMU in real time, and has the function of automatic addressing of multiple SBMUs. Figure 6 In the figure, RX / TX means receive / transmit, CANH and CANL mean high potential and low potential data lines in the CAN bus, and PWM means pulse width modulator.

[0219] MRDB has the same hardware card board as SBMU. MRDB sends the status information of the entire battery management system to the background data center.

[0220] MHVB is integrated into the vehicle's all-in-one controller. Each battery pack has a current Hall sensor. Current detection can be performed on each branch battery pack. MHVB collects the information from the current Hall sensor and converts it into a current value. Then the currents of all branches are added together to get the total current value. MHVB collects the high voltage and insulation resistance of each main line and sends the collected data to MBMU via CAN communication.

[0221] like Figure 7 As shown in the figure, the hardware boards of MBMU and SBMU are the same, which realizes the uniformity of hardware and reduces the development, design and production costs. MBMU is the brain of the entire battery management system, responsible for the information processing, diagnosis, estimation of all battery packs and the verification of SBMU for single pack management. Figure 7 In the figure, RX / TX means receive / transmit, CANH and CANL mean high potential and low potential data lines in the CAN bus, and PWM means pulse width modulator.

[0222] MBMU serves as the main control of the battery management system, and SBMU serves as the main control of a single battery pack. Both have the function of remotely upgrading the software through over-the-air download technology and mobile network communication, and both have the functions of software backup, software AB partitioning, and software rollback. The program upgrade methods are diversified and highly redundant, which improves the security of program upgrades. In addition, they have dual-gun charging and quad-gun charging functions. In the dual-gun charging state, one charging gun can be charged while the other gun can be plugged in and out at any time.

[0223] The dual-charger function means that one charging gun can be charged while the other gun can be plugged in and out at any time, which can improve the utilization rate of charging conditions, increase charging speed, and reduce charging time. Four charging signal detection hardware interfaces can detect four charging gun connection signals and realize the function of charging with four charging guns.

[0224] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware. Moreover, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0225] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram and the combination of the processes and / or blocks in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0226] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0227] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0228] The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A new energy vehicle battery management system, wherein the new energy vehicle battery comprises a plurality of battery packs, each battery pack comprises a plurality of single cells, characterized in that: The system comprises: Single cell data collection controller: used to collect single cell battery data; Single-pack acquisition controller: used to collect data of a single battery pack; Single pack main controller: used to estimate the power of a single battery pack and detect faults based on the data of the single battery and the single battery pack, and obtain the power estimation value and fault detection result of the single battery pack; Single-pack remote transmission controller: used to transmit single-cell battery data, single battery pack data, and single battery pack power estimation value and fault detection results to the background for storage; Total acquisition controller: used to collect total data of all battery packs; The main controller is used to perform a secondary estimation of the power of a single battery pack based on the data of the single battery cell and the data of a single battery pack, and obtain the secondary estimation value of the power of the single battery pack; perform a power estimation of all battery packs based on the total data of all battery packs, and obtain the estimated power values ​​of all battery packs; perform a double check on the primary estimation value of the power of a single battery pack based on the secondary estimation value of the power of a single battery pack and the estimated power values ​​of all battery packs; Total remote transmission controller: used to transmit the total data of all battery packs, the secondary estimated value of the power of a single battery pack, and the estimated value of the power of all battery packs to the background for storage; The single cell data includes the voltage and temperature of the single cell; the single battery pack data includes the high voltage voltage, current, and insulation resistance value of the single battery pack; the total data of all battery packs includes the total high voltage voltage, total current, and total insulation resistance value of all battery packs.

2. The new energy vehicle battery management system according to claim 1, characterized in that: The controllers are connected to each other through a controller area network bus.

3. The new energy vehicle battery management system according to claim 1, characterized in that: The single cell acquisition controller acquires voltage and performs equalization control on the single cell through the first preset chip to obtain the voltage of the single cell, and acquires temperature of the single cell by connecting the temperature sensor to the single cell through the first preset chip to obtain the temperature of the single cell; Wherein, the first preset chip is an AFE chip.

4. The new energy vehicle battery management system according to claim 1, characterized in that: The single-pack acquisition controller acquires the high-voltage voltage, current, and insulation resistance value of a single battery pack through a second preset chip to obtain the high-voltage voltage, current, and insulation resistance value of the single battery pack; Wherein, the second preset chip is the MC33772C chip.

5. The new energy vehicle battery management system according to claim 1, characterized in that: The total acquisition controller acquires the total high voltage voltage and total insulation resistance value of all battery packs by collecting the high voltage voltage and insulation resistance value of the main lines connecting all battery packs, and acquires the branch current of each battery pack by collecting the current of the branch lines connecting each battery pack through the Hall current sensor provided in each battery pack, and acquires the branch current of each battery pack. The branch current of each battery pack is added together to acquire the total current of all battery packs.

6. The new energy vehicle battery management system according to claim 1, characterized in that: The single-pack main controller uses the third preset chip as the central processor and the fourth preset chip as the battery management chip. The third preset chip and the fourth preset chip process the single cell data and the single battery pack data to obtain a primary estimated value of the power of the single battery pack and a fault detection result.

7. The new energy vehicle battery management system according to claim 6, characterized in that: The single-packet main controller wakes up the fourth preset chip through the fifth preset chip to perform battery management.

8. The new energy vehicle battery management system according to claim 6, characterized in that: The fault detection includes sensor fault detection, network fault detection, battery overcharge / overdischarge / overcurrent detection, and insulation fault detection; The sensors include a temperature sensor in the single-cell acquisition controller for acquiring the temperature of a single cell, a shunt in the single-pack acquisition controller for acquiring the current of a single battery pack, and a Hall current sensor in the total acquisition controller for acquiring the branch current of each battery pack; The network failure includes a daisy chain communication connection failure between chips in each of the controllers and a controller area network bus communication connection failure between each of the controllers.

9. The new energy vehicle battery management system according to claim 1, characterized in that: The main controller uses the third preset chip as the central processing unit and the fourth preset chip as the battery management chip. The third preset chip and the fourth preset chip are used to process the single cell data, the single battery pack data, and the total data of all battery packs to obtain the secondary estimated value of the power of the single battery pack and the estimated value of the power of all battery packs. Based on the secondary estimated value of the power of the single battery pack and the estimated value of the power of all battery packs, a double check is performed on the primary estimated value of the power of the single battery pack.

10. The new energy vehicle battery management system according to claim 9, characterized in that: The overall main controller wakes up the fourth preset chip through the fifth preset chip to perform battery management.

11. The new energy vehicle battery management system according to claim 9, characterized in that: The main controller exchanges information with the charging pile to determine the access status of the charging gun. When the charging gun is connected, it sends the currently required charging current and charging voltage to the charging pile, receives the current charging current and charging voltage fed back by the charging pile, performs fault diagnosis on charging faults generated during the charging process, and sends an alarm prompt to the entire vehicle based on the fault diagnosis results.

12. The new energy vehicle battery management system according to claim 9, characterized in that: The overall main controller sends a high-voltage power-on control signal or a high-voltage power-off control signal to the single-package main controller according to the fault detection result, and the single-package main controller controls the main positive contactor and the main negative contactor to close for high-voltage power supply according to the high-voltage power-on control signal, or controls the main positive contactor and the main negative contactor to open for high-voltage power-off according to the high-voltage power-off control signal.

13. The new energy vehicle battery management system according to claim 9, characterized in that: The main controller sends a heat dissipation signal to the vehicle multi-source thermal management system according to the temperature of the single battery collected by the single battery collection controller, and the vehicle multi-source thermal management system dissipates heat according to the heat dissipation signal; wherein the heat dissipation signal includes an enable signal and a preset temperature signal.

14. The new energy vehicle battery management system according to any one of claims 6 to 13, characterized in that: The third preset chip is a TC387 chip, and the fourth preset chip is a TLF35584 chip.

15. The new energy vehicle battery management system according to any one of claims 7 or 10, characterized in that: The fifth preset chip is an RTC chip.

16. The new energy vehicle battery management system according to claim 1, characterized in that: The single-package main controller and the master main controller can remotely upgrade the software through over-the-air download technology and mobile network communication, and both have software backup, software AB partitioning, and software rollback functions.

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