Motor inverter step-up type DC bus voltage matching system of double high-voltage battery pack

Abstract

This invention discloses a boost DC bus voltage matching system for a motor inverter with dual high-voltage battery packs, comprising a battery management system, battery pack A, battery pack B, main negative contactor R2, main positive contactor R3, main negative contactor R4, a first voltage sensor, a first current sensor, a second voltage sensor, a second current sensor, a third voltage sensor, a vehicle control unit, a generator control module, an inverter, a generator, a relay Rb, current sensors a1, b1, and c1, a DC link capacitor bank CDC, a power inverter module, a motor controller, current sensors a2, b2, and c2, and a traction motor. The invention features a highly integrated hardware architecture, effectively reducing system cost and space occupation, enabling seamless battery pack switching during driving, effectively suppressing surge current, protecting high-voltage components and ensuring power stability, improving system fault tolerance, and enhancing the operational reliability of the high-voltage system.

Description

Technical Field

[0001] This invention relates to a boost DC bus voltage matching system for a motor inverter with dual high-voltage battery packs. Background Technology

[0002] The technical challenges of DC bus voltage matching and battery pack operating mode switching in dual high-voltage battery pack systems have been addressed in various solutions for mass-produced electric vehicles. These solutions fall into three main categories. The first is a solution where the power distribution unit (PDU) controls the charging and discharging of multiple battery packs. This is the foundational solution for multi-pack high-voltage architectures. Its core functionality involves integrated power distribution units to manage the charging and discharging of multiple battery packs. The PDU integrates the battery management system's main board and main circuit relays, allowing the PDU to uniformly control the on / off switching of the charging and discharging circuits for all high-voltage battery packs. Technically, this requires all battery packs to charge and discharge synchronously, and the voltage difference between each pack must be controlled within the vehicle system's preset allowable range to ensure DC bus voltage stability. The core design logic of this solution is "unified control and synchronous operation," without independent battery... The first type involves switching and voltage matching logic for battery packs. If any battery pack fails, the entire high-voltage circuit of the vehicle must be disconnected, making it impossible to achieve independent power supply for a single pack. The second type is a solution that reuses the traction motor and inverter components to achieve voltage adjustment and switching between the two battery packs. This solution is mainly adapted to the dual-battery pack architecture of pure electric vehicles and is an optimized version of the first type. It reuses the inductor of the vehicle's original traction motor and the power devices of the inverter to replace the dedicated voltage regulation hardware, thereby adjusting the voltage difference between the two high-voltage battery packs A and B and completing the switching of the battery pack's working mode. Technically, a single battery pack usually acts as a "power bank" type auxiliary power source, only supplementing power when the main battery pack's power is insufficient. Moreover, because it only reuses the core hardware of the traction motor and inverter, there is no matching switching control logic and voltage buffer circuit. The voltage adjustment and working mode switching of the battery pack can only be completed when the vehicle is stationary.The third type is a voltage matching scheme that adds a DC-DC converter to the second type of solution. This scheme is an advanced improvement on the second type, primarily addressing the operating condition limitations of the second type. It adds an independent high-voltage DC-DC boost / buck converter to the dual-battery-pack high-voltage architecture. This dedicated hardware compensates for the voltage difference between battery packs A and B, achieving precise DC bus voltage matching and enabling battery pack switching. Technically, this scheme can overcome the limitations of stationary vehicle conditions to some extent, enabling battery pack switching during driving. However, it requires the design of a dedicated DC-DC converter with its drive circuit, cooling system, and control logic, forming a "hardware reuse + dedicated voltage regulation" system with the existing traction motor and inverter. The combined architecture of the above three solutions cannot meet the practical application requirements of seamless switching between dual high-voltage battery packs during the driving of new energy range-extended vehicles, without additional hardware additions, and with effective suppression of surge current. The core technical defects are mainly reflected in four aspects: First, the application scenarios are limited and the adaptability is poor. Neither solution one nor two can achieve seamless switching between dual battery packs during vehicle driving. Solution two relies entirely on the vehicle being stationary to complete voltage adjustment and pack switching, which cannot adapt to the core requirements of range-extended vehicles to switch between range-extended / pure electric modes and extend the range during driving. Although solution three alleviates the scenario limitations, its adaptability is still limited by the power and voltage regulation range of the dedicated DC-DC converter, making it difficult to flexibly match the power supply requirements of dual battery packs with different discharge rates and capacities. Second, the system The complex system architecture increases hardware costs and layout space. To address scenario limitations, Solution 3 requires additional high-voltage DC-DC converters, supporting drive circuits, and heat dissipation components. This not only increases the number of high-voltage components in the vehicle, raising system R&D, production, and integration costs, but also occupies limited vehicle space, reducing the space utilization of the high-voltage system. While Solutions 1 and 2 do not require additional hardware, their redundant power distribution / control logic design still results in high architectural complexity. Thirdly, low fault tolerance leads to poor reliability of the vehicle's high-voltage system. Solution 1 uses a "synchronous charging and discharging, single-pack fault overall disconnection" control logic, lacking fault redundancy. If any battery pack experiences voltage abnormalities or overheating, the entire vehicle's high-voltage circuit stops outputting, significantly reducing... To ensure the reliability of the high-voltage system, while schemes two and three achieve independent operation of a single battery pack, they lack rapid switching logic under fault conditions, resulting in low fault response efficiency. Fourthly, insufficient surge current protection affects the lifespan of high-voltage components and power stability. None of the three existing technical solutions design a progressive voltage matching and buffer circuit for the voltage difference during battery pack switching. Directly connecting battery packs with different voltages to the DC bus easily generates harmful surge currents, which not only overload the DC link capacitors and affect the lifespan of high-voltage components but also cause fluctuations in the vehicle's power output, reducing the smoothness of vehicle operation. In summary, none of the existing technologies meet the requirements of "no additional hardware additions, seamless switching during driving, effective surge current suppression, and coordinated power supply from dual battery packs." Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a boost DC bus voltage matching system for a motor inverter with dual high-voltage battery packs.

[0004] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0005] The dual high-voltage battery pack motor inverter boost DC bus voltage matching system includes a battery management system, battery pack A, battery pack B, main negative contactor R2, main positive contactor R3, main negative contactor R4, first voltage sensor, first current sensor, second voltage sensor, second current sensor, third voltage sensor, vehicle control unit, generator control module, inverter, generator, relay Rb, current sensor a1, current sensor b1, current sensor c1, and DC link capacitor bank C. DC The system comprises a power inverter module, a motor controller, current sensors a2, b2, and c2, and a traction motor. The generator has windings A1, B1, and C1, with a common connection terminal N for windings A1, B1, and C1. The traction motor has windings A2, B2, and C2, with a common connection terminal M for windings A2, B2, and C2. The positive terminal of battery pack A is connected to one end of relay Rb via a first current sensor. A first voltage sensor is connected in parallel with battery pack A. The negative terminal of battery pack A is connected to one end of the inverter via a main negative contactor R2. The first voltage sensor, first current sensor, second voltage sensor, second current sensor, main negative contactor R2, main positive contactor R3, and main negative contactor R4 are all connected to the battery management system. The other end of the relay Rb is connected to the common connection terminal N. Winding A1 is connected to the inverter through current sensor a1, winding B1 is connected to the inverter through current sensor b1, and winding C1 is connected to the inverter through current sensor c1. Current sensors a1, b1, and c1 are all connected to the generator control module. One end of the inverter is controlled by the generator control module via a PWM signal.

[0006] The positive terminal of battery pack B is connected to one end of the main positive contactor R3 via a second current sensor. The other end of the main positive contactor R3 is connected to one end of the power inverter module. The negative terminal of battery pack B is connected to the other end of the power inverter module via a main negative contactor R4. The second voltage sensor is connected in parallel with battery pack B. The other end of the main positive contactor R3 is connected to the other end of the inverter. The other end of the power inverter module is connected to one end of the inverter. The other end of the main positive contactor R3 is connected to the DC link capacitor bank C. DCThe other end of the power inverter module is connected to the power inverter module. Winding A2 is connected to the power inverter module via current sensor a2, winding B2 is connected to the power inverter module via current sensor b2, and winding C2 is connected to the power inverter module via current sensor c2. Current sensors a2, b2, and c2 are all connected to the motor controller. The other end of the power inverter module is controlled by the motor controller via a PWM signal. The third voltage sensor is connected to the DC link capacitor bank C. DC In parallel configuration, the third voltage sensor, generator control module, motor controller, and battery management system are all connected to the vehicle control unit.

[0007] Preferably, the inverter includes power switches S11, S21, S31, S41, S51, and S61. The first terminals of power switches S11, S31, and S51 are all connected to the other end of the main positive contactor R3. The second terminal of power switch S11 is connected to the first terminal of power switch S21, the second terminal of power switch S31 is connected to the first terminal of power switch S41, and the second terminal of power switch S51 is connected to the first terminal of power switch S61. The second terminal of power switch S21 and power switch S41 are connected to the first terminal of power switch S61. The second terminal of 1 and the second terminal of power switch S61 are both connected to the second terminal of the power inverter module. The winding A1 is connected to the second terminal of power switch S11 through current sensor a1. The winding B1 is connected to the second terminal of power switch S31 through current sensor b1. The winding C1 is connected to the second terminal of power switch S51 through current sensor c1. The third terminals of power switches S11, S21, S31, S41, S51, and S61 are all controlled by the generator control module through PWM signals.

[0008] Preferably, the power inverter module includes power switches S1, S2, S3, S4, S5, and S6. The first terminals of power switches S1, S3, and S5 are all connected to the first terminal of power switch S1. The second terminal of power switch S1 is connected to the first terminal of power switch S2, the second terminal of power switch S3 is connected to the first terminal of power switch S4, and the second terminal of power switch S5 is connected to the first terminal of power switch S6. The second terminals of S4 and S6 are both connected to the second terminal of power switch S21. The winding A2 is connected to the second terminal of power switch S1 through current sensor a2. The winding B2 is connected to the second terminal of power switch S3 through current sensor b2. The winding C2 is connected to the second terminal of power switch S5 through current sensor c2. The third terminals of power switches S1, S2, S3, S4, S5, and S6 are all controlled by the motor controller via PWM signals.

[0009] Preferably, power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all Insulated Gate Bipolar Transistors (IGBTs). The first terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all collectors. The second terminal of power switch S11... The second terminals of switch S21, power switch S31, power switch S41, power switch S51, power switch S61, power switch S1, power switch S2, power switch S3, power switch S4, power switch S5, and power switch S6 are all emitters. The third terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all gates.

[0010] Preferably, power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all silicon carbide MOSFETs. The first terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all drain terminals. The second terminal of power switch S11, power switch S2, power switch S3, power switch S4, power switch S5, and power switch S6 are all drain terminals. The second terminals of S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all sources, and the third terminals of S11, S21, S31, S41, S5, S61, S1, S2, S3, S4, S5, and S6 are all gates.

[0011] As a preferred embodiment, a battery management system is used to monitor the electrical parameters of the battery pack and control the on / off state of the contactors, and upload the collected data to the vehicle control unit.

[0012] The battery pack A is used as a high-voltage auxiliary energy storage unit to provide auxiliary power to the system and participate in the collaborative power supply of the dual battery packs;

[0013] The battery pack B is used as a high-voltage main energy storage unit to provide the main power supply to the system and maintain the DC bus base voltage.

[0014] The vehicle control unit serves as the core of the system's overall control, receiving data collected by each module and issuing control commands to coordinate the various components to complete the boost and battery pack switching.

[0015] The generator control module serves as the control core for the inverter and generator, outputting PWM drive signals, acquiring generator phase current, and executing boost control strategies.

[0016] The inverter is used to convert electrical energy and, together with the generator winding, forms a temporary boost circuit to execute the PWM control commands of the generator control module.

[0017] The power inverter module is used to invert the DC power from the DC bus into three-phase AC power to provide frequency and voltage regulation power for the traction motor and execute the PWM control commands of the motor controller.

[0018] The motor controller serves as the control core for the power inverter module and the traction motor, outputting PWM drive signals and acquiring the phase current of the traction motor to control the speed and torque of the traction motor.

[0019] Preferably, the main negative contactor R2 is used to switch the negative power supply circuit of battery pack A on and off, and to control the circuit connection and disconnection of battery pack A.

[0020] The main positive contactor R3 is used to switch the positive power supply circuit of battery pack B on and off, and to control the connection and disconnection of the circuit of battery pack B.

[0021] The main negative contactor R4 is used to switch the negative power supply circuit of battery pack B on and off, and works with the main positive contactor R3 to realize the on and off control of the battery pack B circuit.

[0022] The first voltage sensor is used to detect the real-time terminal voltage VA of battery pack A and upload the real-time terminal voltage VA to the battery management system.

[0023] The first current sensor is used to detect the real-time charging and discharging current IA of battery pack A and upload the charging and discharging current IA to the battery management system.

[0024] The second voltage sensor is used to detect the real-time terminal voltage VB of battery pack B and upload the real-time terminal voltage VB to the battery management system.

[0025] The second current sensor is used to detect the real-time charge and discharge current IB of battery pack B and transmit the real-time charge and discharge current IB to the battery management system.

[0026] The generator is used to provide three-phase winding inductance, and its windings, together with the inverter, form a boost circuit to provide an inductive energy storage carrier for boosting the voltage of battery pack A.

[0027] Preferably, the third voltage sensor is used to detect the DC link capacitor bank C. DC The DC bus voltage VDC at both ends is transmitted and uploaded to the vehicle control unit.

[0028] The relay Rb is used to switch the circuit between the positive terminal of battery pack A and the common connection terminal N of the generator three-phase winding, and to control the connection and disconnection of the boost circuit.

[0029] The current sensor a1 is used to detect the real-time phase current of the generator winding A1, collect the current signal and upload it to the generator control module.

[0030] The current sensor b1 is used to detect the real-time phase current of the generator winding B1, collect the current signal and upload it to the generator control module.

[0031] The current sensor c1 is used to detect the real-time phase current of the generator winding C1, collect the current signal and upload it to the generator control module.

[0032] The DC link capacitor bank C DC It is used to stabilize the DC bus voltage, filter out the switching ripple of the bus voltage, and suppress the surge current during battery pack switching.

[0033] Preferably, the current sensor a2 is used to detect the real-time phase current of the traction motor winding A2, collect the current signal and upload it to the motor controller.

[0034] The current sensor b2 is used to detect the real-time phase current of the traction motor winding B2, collect the current signal and upload it to the motor controller.

[0035] The current sensor c2 is used to detect the real-time phase current of the traction motor winding C2, collect the current signal and upload it to the motor controller.

[0036] The traction motor is used as a vehicle traction power actuator to convert three-phase AC power into mechanical energy and output torque to provide driving power for the vehicle.

[0037] The beneficial effects of this invention are as follows:

[0038] 1. Highly integrated hardware architecture effectively reduces system cost and space occupation: This invention reuses idle components such as the vehicle's original auxiliary range extender generator, inverter, and motor windings to build a temporary boost circuit. There is no need to add a dedicated high-voltage DC-DC converter and supporting drive and heat dissipation components, which greatly simplifies the overall architecture of the dual high-voltage battery pack system, reduces the system's R&D, production and integration costs, and reduces the overall vehicle layout space for high-voltage components, thereby improving the space utilization rate of the high-voltage system.

[0039] 2. Overcoming operating condition limitations and achieving seamless battery pack switching during driving: The invention designs control logic with differential pressure grading, neutral point soft connection, and closed-loop boost regulation, which can complete the mode switching and voltage matching of dual high-voltage battery packs during normal vehicle operation. This breaks through the limitation of existing technologies where battery pack switching requires the vehicle to be stationary, and perfectly adapts to the core usage needs of new energy range-extended vehicles for switching between range-extended and pure electric modes and extending range during driving.

[0040] 3. Effectively suppress surge current, protect high-voltage components and ensure stable power: This invention controls the voltage difference between the battery pack and the DC bus within a safe threshold through differential pressure pre-detection and progressive voltage boost adjustment, and then realizes parallel connection. At the same time, it utilizes the inductive characteristics of the generator winding and the voltage stabilization and filtering effect of the DC link capacitor bank to suppress harmful surge currents during battery pack switching from the source, avoid overload of DC link capacitors, extend the service life of high-voltage components, and ensure the continuity and stability of the vehicle's power output, thereby improving the smoothness of vehicle driving.

[0041] 4. Improve system fault tolerance and enhance the operational reliability of the high-voltage system: This invention constructs a working mode of independent power supply for battery packs and dual-pack collaborative power supply. When any battery pack fails, its power supply circuit can be quickly cut off and the other battery pack can maintain the normal power supply of the system. There is no need to cut off the entire high-voltage circuit of the vehicle, which greatly improves the fault tolerance capability of the system and the overall operational reliability of the high-voltage system.

[0042] 5. Strong adaptability and versatility, compatible with dual battery packs with different electrical characteristics: The control logic of this invention can dynamically adapt to the power supply requirements of dual high-voltage battery packs with different capacities, discharge rates, and internal resistances. After the voltage boost is completed, the auxiliary range extender generator will switch to voltage following mode to finely adjust the DC bus voltage in real time, effectively solving the problem of bus voltage fluctuation caused by the difference in electrical characteristics of dual battery packs. It can be adapted to the high-voltage architecture design of many new energy vehicle models.

[0043] 6. Low engineering implementation difficulty, easy for mass production and upgrading of existing models: The technical solution of this invention can be directly integrated into the powertrain architecture of existing new energy range-extended vehicles without making significant changes to core hardware such as the main electric drive unit and auxiliary range extender generator. Functional expansion can be achieved simply by optimizing the software control strategy. The modification cost is low, it is compatible with existing production lines, and it is easy for mass production and upgrading of high-voltage architecture technology of traditional models. Attached Figure Description

[0044] Figure 1 This is the circuit schematic diagram of the present invention. Detailed Implementation

[0045] The technical solution of the present invention will be further described below:

[0046] like Figure 1As shown, the motor inverter boost DC bus voltage matching system with dual high-voltage battery packs includes a battery management system 1, battery pack A, battery pack B, main negative contactor R2, main positive contactor R3, main negative contactor R4, first voltage sensor 2, first current sensor 3, second voltage sensor 4, second current sensor 5, third voltage sensor 6, vehicle control unit 7, generator control module 8, inverter 9, generator 10, relay Rb, current sensor a1, current sensor b1, current sensor c1, and DC link capacitor bank C. DC The system includes a power inverter module 12, a motor controller 13, current sensors a2, b2, and c2, and a traction motor 11. The generator 10 has windings A1, B1, and C1, with a common connection terminal N for windings A1, B1, and C1. The traction motor 11 has windings A2, B2, and C2, with a common connection terminal M for windings A2, B2, and C2. The positive terminal of battery pack A is connected to one end of relay Rb via a first current sensor 3. A first voltage sensor 2 is connected in parallel with battery pack A. The negative terminal of battery pack A is connected to one end of inverter 9 via a main negative contactor R2. The first voltage sensor 2 and the first current sensor... Sensor 3, second voltage sensor 4, second current sensor 5, main negative contactor R2, main positive contactor R3, and main negative contactor R4 are all connected to the battery management system 1. The other end of the relay Rb is connected to the common connection terminal N. Winding A1 is connected to the inverter 9 through current sensor a1, winding B1 is connected to the inverter 9 through current sensor b1, and winding C1 is connected to the inverter 9 through current sensor c1. Current sensors a1, b1, and c1 are all connected to the generator control module 8. That is, the power switches S11, S21, S31, S41, S51, and S61 of the inverter 9 are controlled by the generator control module 8 through PWM signals. The DC link capacitor bank C... DC The upper end is the positive terminal of the DC bus, and the DC link capacitor bank C DC The lower end is the negative terminal of the DC bus.

[0047] The positive terminal of battery pack B is connected to one end of the main positive contactor R3 via the second current sensor 5. The other end of the main positive contactor R3 is connected to one end of the power inverter module 12. The negative terminal of battery pack B is connected to the other end of the power inverter module 12 via the main negative contactor R4. The second voltage sensor 4 is connected in parallel with battery pack B. The other end of the main positive contactor R3 is connected to the other end of inverter 9. The other end of the power inverter module 12 is connected to one end of inverter 9. The other end of the main positive contactor R3 is connected to the DC link capacitor bank C. DCThe other end of the power inverter module 12 is connected to the power inverter module 12 via current sensor a2, winding B2 via current sensor b2, and winding C2 via current sensor c2. Current sensors a2, b2, and c2 are all connected to the motor controller 13. The other end of the power inverter module 12 is controlled by the motor controller 13 via a PWM signal. That is, the third terminals of the power switches S1 to S6 of the power inverter module 12 are all controlled by the motor controller 13 via PWM signals. The third voltage sensor 6 is connected to the DC link capacitor bank C. DC The third voltage sensor 6, generator control module 8, motor controller 13, and battery management system 1 are all connected to the vehicle control unit 7 in parallel.

[0048] like Figure 1 As shown, the inverter 9 includes power switches S11, S21, S31, S41, S51, and S61. The first terminals of power switches S11, S31, and S51 are all connected to the other end of the main positive contactor R3. The second terminal of power switch S11 is connected to the first terminal of power switch S21, the second terminal of power switch S31 is connected to the first terminal of power switch S41, and the second terminal of power switch S51 is connected to the first terminal of power switch S61. The second terminal of power switch S21 and the second terminal of power switch S41 are connected to the first terminal of power switch S61. The second terminal of power switch S61 is connected to the second terminal of power inverter module 12. The winding A1 is connected to the second terminal of power switch S11 through current sensor a1. The winding B1 is connected to the second terminal of power switch S31 through current sensor b1. The winding C1 is connected to the second terminal of power switch S51 through current sensor c1. The third terminals of power switches S11, S21, S31, S41, S51, and S61 are all controlled by generator control module 8 through PWM signals.

[0049] like Figure 1As shown, the power inverter module 12 includes power switches S1, S2, S3, S4, S5, and S6. The first terminals of power switches S1, S3, and S5 are all connected to the positive input terminal of inverter 9. The positive input terminal of inverter 9 is the first terminal of power switch S11. The first terminals of power switches S1, S3, and S5 are the DC positive terminals of power inverter module 12, directly connected to the positive input terminal of inverter 9 and the positive terminal of the DC bus. The second terminal of power switch S1 is connected to the first terminal of power switch S2, the second terminal of power switch S3 is connected to the first terminal of power switch S4, and the second terminal of power switch S5 is connected to the first terminal of power switch S6. The second terminals of power switches S4 and S6 are all connected to the DC negative input terminal of inverter 9. The DC negative input terminal of inverter 9 is the second terminal of power switch S21. The second terminals of S2, S4, and S6 are the DC negative terminals of power inverter module 12, which are directly connected to the DC negative input terminal of inverter 9 and the negative terminal of DC bus. The winding A2 is connected to the second terminal of power switch S1 through current sensor a2. The winding B2 is connected to the second terminal of power switch S3 through current sensor b2. The winding C2 is connected to the second terminal of power switch S5 through current sensor c2. The third terminals of power switches S1, S2, S3, S4, S5, and S6 are controlled by motor controller 13 through PWM signals.

[0050] like Figure 1As shown, power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all Insulated Gate Bipolar Transistors (IGBTs). The first terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all collectors. The second terminal of power switch S11... The second terminals of S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all emitters. The third terminals of S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all gates.

[0051] like Figure 1As shown, power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all silicon carbide MOSFETs. The first terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all drain terminals. The second terminals of power switches S11 and S21 are all drain terminals. The second terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all sources. The third terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S3, S4, S5, and S6 are all gates.

[0052] like Figure 1 As shown, the battery management system 1 is used to monitor the electrical parameters of the battery pack and control the on / off state of the contactors, and upload the collected data to the vehicle control unit 7.

[0053] The battery pack A is used as a high-voltage auxiliary energy storage unit to provide auxiliary power to the system and participate in the collaborative power supply of the dual battery packs;

[0054] Battery pack B is used as a high-voltage main energy storage unit to provide the main power supply to the system and maintain the DC bus base voltage;

[0055] The vehicle control unit 7 serves as the core of the system's overall control, receiving data collected from each module and issuing control commands to coordinate the various components to complete the boost and battery pack switching.

[0056] Generator control module 8 is used as the control core of inverter 9 and generator 10, outputting PWM drive signals and acquiring the phase current of generator 10, and executing boost control strategy.

[0057] Inverter 9 is used to convert electrical energy and, together with the winding of generator 10, forms a temporary boost circuit to execute the PWM control commands of generator control module 8.

[0058] The power inverter module 12 is used to invert the DC power from the DC bus into three-phase AC power to provide frequency and voltage regulation power for the traction motor 11 and execute the PWM control commands of the motor controller 13.

[0059] The motor controller 13 serves as the control core for the power inverter module 12 and the traction motor 11, outputting PWM drive signals and acquiring the phase current of the traction motor 11 to control the speed and torque of the traction motor 11.

[0060] like Figure 1 As shown, the main negative contactor R2 is used to switch the negative power supply circuit of battery pack A on and off, and to control the connection and disconnection of the circuit of battery pack A.

[0061] The main positive contactor R3 is used to switch the positive power supply circuit of battery pack B on and off, and to control the connection and disconnection of the circuit of battery pack B.

[0062] The main negative contactor R4 is used to switch the negative power supply circuit of battery pack B on and off, and works with the main positive contactor R3 to realize the on and off control of the battery pack B circuit.

[0063] The first voltage sensor 2 is used to detect the real-time terminal voltage VA of battery pack A and upload the real-time terminal voltage VA to the battery management system 1;

[0064] The first current sensor 3 is used to detect the real-time charging and discharging current IA of battery pack A and upload the charging and discharging current IA to the battery management system 1.

[0065] The second voltage sensor 4 is used to detect the real-time terminal voltage VB of battery pack B and upload the real-time terminal voltage VB to the battery management system 1.

[0066] The second current sensor 5 is used to detect the real-time charging and discharging current IB of the battery pack B and transmit the real-time charging and discharging current IB to the battery management system 1.

[0067] Generator 10 is used to provide three-phase winding inductance. Its windings, together with inverter 9, form a boost circuit to provide inductive energy storage carrier for boosting battery pack A.

[0068] The third voltage sensor 6 is used to detect the DC link capacitor bank C. DC The DC bus voltage VDC at both ends is transmitted and uploaded to the vehicle control unit 7.

[0069] Relay Rb is used to switch the circuit between the positive terminal of battery pack A and the common connection terminal N of the three-phase winding of generator 10, and to control the connection and disconnection of the boost circuit.

[0070] The current sensor a1 is used to detect the real-time phase current of the generator winding A1, collect the current signal and upload it to the generator control module 8;

[0071] The current sensor b1 is used to detect the real-time phase current of the generator 10 winding B1, collect the current signal and upload it to the generator control module 8;

[0072] The current sensor C1 is used to detect the real-time phase current of the generator winding C1, collect the current signal and upload it to the generator control module 8.

[0073] DC link capacitor bank C DC It is used to stabilize the DC bus voltage, filter out the switching ripple of the bus voltage, and suppress the surge current during battery pack switching.

[0074] The current sensor a2 is used to detect the real-time phase current of the winding A2 of the traction motor 11, collect the current signal and upload it to the motor controller 13;

[0075] The current sensor b2 is used to detect the real-time phase current of the winding B2 of the traction motor 11, collect the current signal and upload it to the motor controller 13;

[0076] The current sensor c2 is used to detect the real-time phase current of the winding C2 of the traction motor 11, collect the current signal and upload it to the motor controller 13;

[0077] The traction motor 11 is used as a vehicle traction power execution unit to convert three-phase AC power into mechanical energy and output torque to provide driving power for the vehicle.

[0078] The working principle is as follows:

[0079] The core control logic of this invention revolves around the entire process of "differential voltage prediction - hardware reuse boost - seamless parallel connection - collaborative voltage stabilization," with the vehicle control unit 7 as the central control core. Through the three-level collaboration of the battery management system 1 generator control module 8 and the motor controller 13, precise matching of the DC bus voltage of the two high-voltage battery packs and seamless switching without power interruption are achieved during driving. The entire control process is based on... Figure 1 The electronic component signal interaction and power circuit operation are divided into six core stages: initialization and status monitoring, differential voltage judgment and mode selection, boost mode control, direct parallel mode control, dual-packet coordinated power supply and reset, and fault protection. The specific principles are as follows:

[0080] I. Initialization and Status Monitoring Phase (System Power-On / Entire Driving Process)

[0081] During system power-on or vehicle operation, all core electronic components enter their working state according to preset logic, completing basic data acquisition and status reporting to provide a basis for subsequent control.

[0082] The battery management system 1 collects and controls the status of the main negative contactor R2, main positive contactor R3, and main negative contactor R4, which are initially in the open state (R3 and R4 are closed only when battery pack B is the default main power supply pack); it collects the voltage VA at the A terminal of battery pack through the first voltage sensor 2, the current IA in the A circuit of battery pack through the first current sensor 3, the voltage VB at the B terminal of battery pack through the second voltage sensor 4, and the current IB in the B circuit of battery pack through the second current sensor 5, and uploads VA, IA, VB, IB and the contactor status to the vehicle control unit 7 in real time.

[0083] Reference data acquisition for vehicle control unit 7: Data is acquired via the third voltage sensor 6 from the DC link capacitor bank C. DC The DC bus voltage VDC at both ends (i.e., the bus reference voltage when battery pack B is powered) is received, and the device ready signal uploaded by generator control module 8 and motor controller 13 is received to confirm that there are no hardware faults in inverter 9, power inverter module 12, generator 10 and traction motor 11.

[0084] The traction control of the motor controller 13 is ready: it outputs PWM signals in real time to control the on / off state of S1~S6 of the power inverter module 12, driving the traction motor 11 to work; it collects the phase current of the traction motor windings A2, B2, and C2 through current sensors a2, b2, and c2 to realize closed-loop control of traction power, and at the same time feeds back the traction motor working status and bus voltage to the vehicle control unit 7 to ensure normal vehicle operation.

[0085] Standby monitoring of generator control module 8: When the control relay Rb is initially disconnected, the no-load current of generator 10 windings A1, B1, and C1 is collected through current sensors a1, b1, and c1 to confirm that there is no short circuit fault in the generator windings. Inverter 9's S11~S61 are in the off standby state, waiting for the boost command.

[0086] II. Differential Pressure Determination and Mode Selection Stage (After Switching Trigger)

[0087] When the vehicle control unit 7 receives a battery pack switching command (such as low battery pack B or the driver switching to dual-pack power supply mode), it immediately performs differential pressure determination and selects either boost mode or direct parallel mode based on the determination result. This is the core decision-making process.

[0088] Switching trigger conditions: The vehicle control unit 7 determines that battery pack A needs to be connected to the bus based on the SOC and voltage data uploaded by the battery management system 1 or the driver's operation command, and initiates the switching process.

[0089] Pressure difference calculation: The vehicle control unit 7 compares the terminal voltage VA of battery pack A (collected by the first voltage sensor 2) with the DC bus voltage VDC (collected by the third voltage sensor 6) and calculates the pressure difference ΔV = |VDC - VA|.

[0090] Mode selection logic:

[0091] If ΔV≤5%×VDC: it is determined to be a small differential pressure condition, and the direct parallel mode is executed without pressure boosting;

[0092] If ΔV > 5% × VDC: it is determined to be a large differential pressure condition, and the boost mode is executed. A temporary boost circuit is constructed by reusing inverter 9 and generator 10 to boost the voltage of battery pack A.

[0093] III. Pressure Boosting Mode Control (Core Invention Point, High Pressure Differential Condition)

[0094] In this mode, the vehicle control unit 7 coordinates the overall scheduling, and the generator control module 8 acts as the execution core. It reuses the S11~S61 of the inverter 9 and the three-phase windings (A1, B1, C1) of the generator 10, and combines them with the relay Rb to construct a temporary boost circuit to achieve a gradual increase in the voltage of the battery pack A. The power inverter module 12 maintains the power output of the traction motor 11 throughout the entire process without interruption.

[0095] Boost circuit construction (hardware action):

[0096] The vehicle control unit 7 sends a command to the battery management system 1 to close the main negative contactor R2 and connect the negative terminal circuit of battery pack A;

[0097] A command is sent to the generator control module 8 to close the relay Rb, so that the positive terminal of the battery pack A (via the first current sensor 3) is connected to the common connection terminal N of the three-phase winding of the generator 10, thus completing the hardware topology construction of the boost circuit.

[0098] Special note,

[0099] upper and lower bridge arm switches of generator inverter 9

[0100] Upper bridge arm switches: S11, S31, S51 (upper power switches of the three-phase bridge arm, the first terminal is connected to the positive terminal of the DC bus)

[0101] Lower bridge arm switches: S21, S41, S61 (lower power switches of the three-phase bridge arm, the second terminal is connected to the negative terminal of the DC bus)

[0102] upper and lower bridge arm switches of the power inverter module (12)

[0103] Upper bridge arm switches: S1, S3, S5 (upper power switches of the three-phase bridge arm, the first terminal is connected to the positive terminal of the DC bus)

[0104] Lower bridge arm switches: S2, S4, S6 (lower power switches of the three-phase bridge arm, the second terminal is connected to the negative terminal of the DC bus).

[0105] Boost control strategy (software modulation):

[0106] The vehicle control unit 7 sends a boost target command to the generator control module 8. Based on the target, the generator control module 8 outputs a PWM drive signal to control the lower arm power switches (S21, S41, S61) of the inverter 9 to switch on and off in a time-sharing manner (preferably selecting any phase, such as S21), and the upper arm power switches (S11, S31, S51) serve as freewheeling branches.

[0107] Energy storage stage: When the lower bridge arm switch (such as S21, S41 or S61) is turned on, the electrical energy of battery pack A forms a circuit through the main negative contactor R2, the lower bridge arm of inverter 9, generator winding A1, common connection terminal N, relay Rb and first current sensor 3. The generator winding A1 acts as a boost inductor to convert electrical energy into magnetic energy for storage. The current sensor a1 collects the winding current and feeds it back to the generator control module 8 to realize current closed loop.

[0108] Energy release stage: When the lower bridge arm switch (such as S21, S41 or S61) is turned off, the magnetic energy of the generator winding A1 is released, generating an induced electromotive force, which is superimposed on the VA of the battery pack A. Through the freewheeling effect of the upper bridge arm switch S11 of the inverter 9, the energy is fed back to the DC bus (the rear end of the main positive contactor R3), thereby increasing the voltage of the battery pack A.

[0109] Closed-loop voltage regulation and termination conditions:

[0110] The generator control module 8 collects the winding current in real time through current sensors a1, b1, and c1, and dynamically adjusts the PWM duty cycle (the larger the duty cycle, the higher the boost ratio).

[0111] The vehicle control unit 7 monitors VA in real time through the first voltage sensor 2. When ΔV drops to the safety threshold, which is set to 3%~5%×VDC, it immediately sends a stop boost command to the generator control module 8. The inverter 9 stops PWM modulation via S11~S61, and the boost process ends, realizing the direct parallel control mode of the dual battery packs.

[0112] IV. Direct Parallel Control Mode (Small Differential Pressure Condition)

[0113] In this mode, generator 10 switches from boost mode to voltage follower mode, utilizing the inductive characteristics of generator 10 windings to achieve a "soft connection," avoiding the small surge current generated by direct parallel connection. The process is simple and involves no boost operation.

[0114] Soft connection preparation: The vehicle control unit 7 instructs the battery management system 1 to close the main negative contactor R2, and instructs the generator control module 8 to close the relay Rb, so that the battery pack A can be indirectly softly connected to the bus through the generator winding common connection terminal N;

[0115] Formal Parallel Connection: After the soft connection is completed, battery pack A and battery pack B are formally connected in parallel and are powered together through the DC bus.

[0116] Buffer protection: The three-phase winding inductance of generator 10 buffers the current surge caused by a small voltage difference, in conjunction with the DC link capacitor bank C. DC The filtering and voltage regulation completely eliminates surge current.

[0117] V. Dual-packet coordinated power supply and reset phase (after switching is completed)

[0118] After battery pack A is successfully connected to the bus, the system enters a dual-packet collaborative power supply state, and at the same time completes the reset of the boost hardware to ensure long-term stable operation of the system.

[0119] Dual-packet collaborative power supply control:

[0120] The battery management system 1 uses the first current sensor 3 and the second current sensor 5 to evenly distribute the charging and discharging current of battery packs A and B, so as to avoid overloading of a single pack.

[0121] According to the power requirements of the whole vehicle, the motor controller 13 dynamically adjusts the PWM parameters of S1~S6 of the power inverter module 12 to adapt to the bus voltage characteristics after dual power supply, so as to ensure the stable power output of the traction motor (11).

[0122] Boost hardware reset:

[0123] The generator control module 8 first controls the relay Rb to disconnect, thus disconnecting the battery pack A from the generator winding;

[0124] Inverter 9 returns to standby shutdown state via S11~S61, and generator control module 8 switches to voltage follower mode, only monitoring the bus voltage in real time and no longer performing boost operation. When the bus voltage fluctuates slightly, it can be fine-tuned through inverter 9.

[0125] Once the dual-power supply is stable, generator 10 and inverter 9 return to a completely idle standby state, awaiting the next switching command.

[0126] VI. Fault Protection and Control (Full Coverage)

[0127] The vehicle control unit 7 receives fault signals from each module in real time. Once a protection condition is triggered, it immediately executes tiered protection actions to ensure the safety of the high-voltage system.

[0128] Overcurrent protection: If the first current sensor 3 or the second current sensor 5 detects that the battery pack current exceeds the limit, or the current sensors a1, a2, etc. detect that the winding current exceeds the limit, the vehicle control unit 7 immediately instructs the battery management system 1 to disconnect the corresponding contactor (R2, R3 or R4), and the generator control module 8 and the motor controller 1 shut off all power switches (S11~S61, S1~S6).

[0129] Overvoltage / undervoltage protection: If the third voltage sensor 6 detects that the bus voltage VDC exceeds the safe range, or if the first voltage sensor 2 and the second voltage sensor 4 detect that the battery pack voltage is abnormal, the vehicle control unit 7 will immediately stop the boost or parallel operation and disconnect the faulty battery pack circuit.

[0130] Power interruption protection: If the inverter 9 or generator 10 fails during the boost process, the vehicle control unit 7 will immediately terminate the boost, maintain the independent power supply of battery pack B, ensure that the power output of traction motor 11 is not interrupted, and only stop the connection process of battery pack A.

[0131] This invention provides a DC bus voltage matching system for a motor inverter with dual high-voltage battery packs, suitable for new energy vehicles with dual high-voltage battery packs. It enables alternating or coordinated power supply from the battery packs while the vehicle is in motion. When the vehicle switches from a low-voltage battery pack to a high-voltage battery pack, this invention effectively solves the problem of harmful surge current caused by the voltage difference between the two battery packs, preventing overload and damage to the DC link capacitor bank caused by surge current, while ensuring stable and fluctuation-free vehicle power output. To eliminate the aforementioned electrical transient impacts without requiring a dedicated high-voltage DC-DC boost converter, this invention reuses the secondary drive unit (generator, inverter, generator control module) that is idle during vehicle operation. By selectively connecting the low-voltage battery pack to the neutral point of the motor windings and coordinating the control of the motor winding inductance and inverter power switching devices, the secondary drive unit is reconfigured into a temporary boost circuit, completing DC link voltage pre-equalization matching before the battery packs are connected to the DC bus. This integrated architecture effectively protects the DC link capacitor bank, achieving seamless switching between the dual high-voltage battery packs and DC bus voltage regulation control without requiring the vehicle to stop.

[0132] It should be noted that the above examples are merely one specific embodiment of the present invention. Obviously, the present invention is not limited to the above embodiments and many variations are possible. In short, all variations that can be directly derived or conceived by those skilled in the art from the content disclosed in this invention should be considered within the scope of protection of this invention.

Claims

1. A DC bus voltage matching system for a motor inverter with dual high-voltage battery packs, characterized in that, Includes a battery management system (1), battery pack A, battery pack B, main negative contactor R2, main positive contactor R3, main negative contactor R4, first voltage sensor (2), first current sensor (3), second voltage sensor (4), second current sensor (5), third voltage sensor (6), vehicle control unit (7), generator control module (8), inverter (9), generator (10), relay Rb, current sensor a1, current sensor b1, current sensor c1, and DC link capacitor bank C. DC The generator (10) has windings A1, B1, and C1, with a common connection terminal N for windings A1, B1, and C1. The traction motor (11) has windings A2, B2, and C2, with a common connection terminal M for windings A2, B2, and C2. The positive terminal of the battery pack A is connected to one end of the relay Rb through the first current sensor (3). The first voltage sensor (2) is connected in parallel with the battery pack A. The negative terminal of the battery pack A is connected to one end of the inverter (9) through the main negative contactor R2. The first voltage sensor (2), the first current sensor (3), the second voltage sensor (4), the second current sensor (5), the main negative contactor R2, the main positive contactor R3, and the main negative contactor R4 are all connected to the battery management system (1). The other end of the relay Rb is connected to the common connection terminal N. The winding A1 is connected to the inverter (9) through the current sensor a1. The winding B1 is connected to the inverter (9) through the current sensor b1. The winding C1 is connected to the inverter (9) through the current sensor c1. The current sensors a1, b1, and c1 are all connected to the generator control module (8). One end of the inverter (9) is controlled by the generator control module (8) through a PWM signal. The positive terminal of battery pack B is connected to one end of the main positive contactor R3 via the second current sensor (5), and the other end of the main positive contactor R3 is connected to one end of the power inverter module (12). The negative terminal of battery pack B is connected to the other end of the power inverter module (12) via the main negative contactor R4. The second voltage sensor (4) is connected in parallel with battery pack B. The other end of the main positive contactor R3 is connected to the other end of the inverter (9), and the other end of the power inverter module (12) is connected to one end of the inverter (9). The other end of the main positive contactor R3 is connected to the DC link capacitor bank C. DC The other end of the power inverter module (12) is connected. Winding A2 is connected to the power inverter module (12) through current sensor a2, winding B2 is connected to the power inverter module (12) through current sensor b2, and winding C2 is connected to the power inverter module (12) through current sensor c2. Current sensors a2, b2, and c2 are all connected to the motor controller (13). The other end of the power inverter module (12) is controlled by the motor controller (13) through a PWM signal. The third voltage sensor (6) is connected to the DC link capacitor group C. DC The third voltage sensor (6), generator control module (8), motor controller (13), and battery management system (1) are all connected to the vehicle control unit (7) in parallel.

2. The motor inverter boost DC bus voltage matching system with dual high-voltage battery packs according to claim 1, characterized in that, The inverter (9) includes power switches S11, S21, S31, S41, S51, and S61. The first ends of power switches S11, S31, and S51 are all connected to the other end of the main positive contactor R3. The second end of power switch S11 is connected to the first end of power switch S21, the second end of power switch S31 is connected to the first end of power switch S41, and the second end of power switch S51 is connected to the first end of power switch S61. The second ends of power switches S21 and S41 are connected to the first end of power switch S61. The second terminal of the power switch S61 is connected to the second terminal of the power inverter module (12). The winding A1 is connected to the second terminal of the power switch S11 through the current sensor a1. The winding B1 is connected to the second terminal of the power switch S31 through the current sensor b1. The winding C1 is connected to the second terminal of the power switch S51 through the current sensor c1. The third terminals of the power switches S11, S21, S31, S41, S51, and S61 are all connected to the generator control module (8) and controlled by the PWM signal.

3. The motor inverter boost DC bus voltage matching system with dual high-voltage battery packs according to claim 2, characterized in that, The power inverter module (12) includes power switches S1, S2, S3, S4, S5, and S6. The first terminals of power switches S1, S3, and S5 are all connected to the first terminal of power switch S11. The second terminal of power switch S1 is connected to the first terminal of power switch S2. The second terminal of power switch S3 is connected to the first terminal of power switch S4. The second terminal of power switch S5 is connected to the first terminal of power switch S6. The second terminals of power switches S2 and S4 are connected to the first terminal of power switch S6. The second end of the power switch S1 and the second end of the power switch S6 are both connected to the second end of the power switch S21. The winding A2 is connected to the second end of the power switch S1 through the current sensor a2. The winding B2 is connected to the second end of the power switch S3 through the current sensor b2. The winding C2 is connected to the second end of the power switch S5 through the current sensor c2. The third ends of the power switches S1, S2, S3, S4, S5 and S6 are controlled by the motor controller (13) through PWM signals.

4. The motor inverter boost DC bus voltage matching system with dual high-voltage battery packs according to claim 3, characterized in that, Power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all Insulated Gate Bipolar Transistors (IGBTs). The first terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all collectors. The second terminal of power switch S11... The second terminals of S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all emitters. The third terminals of S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all gates.

5. The motor inverter boost DC bus voltage matching system with dual high-voltage battery packs according to claim 3, characterized in that, Power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all silicon carbide MOSFETs. The first terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all drain terminals. The second terminals of power switches S11 and S21 are all drain terminals. The second terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S4, S5, and S6 are all sources. The third terminals of power switches S11, S21, S31, S41, S51, S61, S1, S2, S3, S3, S4, S5, and S6 are all gates.

6. The motor inverter boost DC bus voltage matching system with dual high-voltage battery packs according to claim 3, characterized in that, The battery management system (1) is used to monitor the electrical parameters of the battery pack and control the on / off state of the contactor, and upload the collected data to the vehicle control unit (7). The battery pack A is used as a high-voltage auxiliary energy storage unit to provide auxiliary power to the system and participate in the collaborative power supply of the dual battery packs; The battery pack B is used as a high-voltage main energy storage unit to provide the main power supply to the system and maintain the DC bus base voltage. The vehicle control unit (7) is used as the core of system overall control, receiving data collected by each module and issuing control commands, and coordinating each component to complete the boost and battery pack switching. The generator control module (8) is used as the control core of the inverter (9) and generator (10), outputs PWM drive signal and collects the phase current of generator (10) to execute boost control strategy; The inverter (9) is used to convert electrical energy and, together with the winding of the generator (10), forms a temporary boost circuit to execute the PWM control command of the generator control module (8). The power inverter module (12) is used to invert the DC power of the DC bus into three-phase AC power, provide frequency and voltage regulation power supply for the traction motor (11), and execute the PWM control command of the motor controller (13); The motor controller (13) is used as the control core of the power inverter module (12) and the traction motor (11), outputs PWM drive signals and collects the phase current of the traction motor (11), and controls the speed and torque of the traction motor (11).

7. The motor inverter boost DC bus voltage matching system with dual high-voltage battery packs according to claim 3, characterized in that, The main negative contactor R2 is used to switch the negative power supply circuit of battery pack A on and off, and to control the connection and disconnection of the circuit of battery pack A. The main positive contactor R3 is used to switch the positive power supply circuit of battery pack B on and off, and to control the connection and disconnection of the circuit of battery pack B. The main negative contactor R4 is used to switch the negative power supply circuit of battery pack B on and off, and works with the main positive contactor R3 to realize the on and off control of the battery pack B circuit. The first voltage sensor (2) is used to detect the real-time terminal voltage VA of battery pack A and upload the real-time terminal voltage VA to the battery management system (1). The first current sensor (3) is used to detect the real-time charging and discharging current IA of battery pack A and upload the charging and discharging current IA to the battery management system (1). The second voltage sensor (4) is used to detect the real-time terminal voltage VB of the battery pack B and upload the real-time terminal voltage VB to the battery management system (1). The second current sensor (5) is used to detect the real-time charging and discharging current IB of the battery pack B and transmit the real-time charging and discharging current IB to the battery management system (1). The generator (10) is used to provide three-phase winding inductance. Its windings and the inverter (9) work together to form a boost circuit to provide an inductive energy storage carrier for boosting the battery pack A.

8. The motor inverter boost DC bus voltage matching system with dual high-voltage battery packs according to claim 3, characterized in that, The third voltage sensor (6) is used to detect the DC link capacitor bank C. DC The DC bus voltage VDC at both ends is transmitted to the vehicle control unit (7). The relay Rb is used to switch the circuit between the positive terminal of battery pack A and the common connection terminal N of the three-phase winding of generator (10), and to control the connection and disconnection of the boost circuit; The current sensor a1 is used to detect the real-time phase current of the generator (10) winding A1, collect the current signal and upload it to the generator control module (8). The current sensor b1 is used to detect the real-time phase current of the generator (10) winding B1, collect the current signal and upload it to the generator control module (8). The current sensor c1 is used to detect the real-time phase current of the generator (10) winding C1, collect the current signal and upload it to the generator control module (8). The DC link capacitor bank C DC It is used to stabilize the DC bus voltage, filter out the switching ripple of the bus voltage, and suppress the surge current during battery pack switching.

9. The motor inverter boost DC bus voltage matching system with dual high-voltage battery packs according to claim 3, characterized in that, The current sensor a2 is used to detect the real-time phase current of the winding A2 of the traction motor (11), collect the current signal and upload it to the motor controller (13). The current sensor b2 is used to detect the real-time phase current of the winding B2 of the traction motor (11), collect the current signal and upload it to the motor controller (13). The current sensor c2 is used to detect the real-time phase current of the winding C2 of the traction motor (11), collect the current signal and upload it to the motor controller (13). The traction motor (11) is used as a vehicle traction power execution unit to convert three-phase AC power into mechanical energy and output torque to provide driving power for the vehicle.

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