Multi-phase motor segmented regenerative braking staged energy recovery management control method and system

Abstract

The application discloses a segmented regenerative braking hierarchical energy recovery management control method and system of a multiphase motor, and belongs to the technical field of motor drive system control. The method is applied to a vehicle configured with a double three-phase motor, and comprises the following steps: acquiring vehicle braking state parameters, battery system state parameters and motor operating state parameters; determining a braking working condition type according to the vehicle braking state parameters, and determining an energy recovery constraint condition according to the battery system state parameters and the motor operating state parameters; determining a target energy recovery level from a plurality of energy recovery levels according to the braking working condition type and the energy recovery constraint condition, and determining a corresponding winding switching combination mode; and controlling each phase winding to be put into or cut off according to the determined winding switching combination mode, and executing regenerative braking energy recovery. The application realizes fine energy recovery management in all working conditions through multi-level segmentation configuration, improves energy recovery efficiency and braking smoothness, and improves braking safety through a step-by-step degradation fault tolerance mechanism.

Description

Technical Field

[0001] This application belongs to the field of control technology for electric motor drive systems of new energy vehicles, specifically relating to a multiphase motor segmented regenerative braking graded energy recovery management and control method and system. Background Technology

[0002] With the popularization of new energy vehicles, regenerative braking technology has become an important means to improve the energy efficiency of the entire vehicle. Regenerative braking utilizes the drive motor to operate in generator mode during braking, converting the vehicle's kinetic energy into electrical energy to recharge the power battery. Multiphase motors (especially dual three-phase motors) are increasingly widely used in new energy commercial vehicles and high-end passenger vehicles due to their high reliability, strong fault tolerance, and high power density. Dual three-phase motors have two independent sets of three-phase windings, each driven by an independent inverter bridge arm, providing a hardware basis for segmented switching of the windings.

[0003] In existing technologies, regenerative braking of dual three-phase motors generally adopts a full six-phase constant-equal-sharing feedback control scheme, that is, six-phase synchronous pulse width modulation throughout the regenerative braking process, adjusting the feedback power only by increasing or decreasing the current of each phase as a whole. However, under light recovery conditions, the small no-load loss (including switching loss and copper loss) generated by the synchronous conduction of the six-phase windings accounts for a relatively high proportion of the total recovered energy, resulting in low actual net recovery benefits; the minimum feedback power is limited, leading to abrupt dragging when the recovery is too strong at low speeds, and loss of energy if recovery is directly shut off. When the battery is fully charged or undercharged, the feedback current can only be reduced as a whole or mechanical braking can be switched, with excess kinetic energy dissipated through friction braking or bleed resistors. When a single-phase winding or power device failure occurs, the entire machine disengages from regenerative braking, instantly losing all electrical braking force.

[0004] Overall, existing regenerative braking control schemes for dual three-phase motors lack a hierarchical energy recovery management mechanism based on multi-dimensional coupling parameters, and cannot balance energy recovery efficiency, braking smoothness, and fault safety across the entire operating range. Summary of the Invention

[0005] The purpose of this application is to provide a multiphase motor segmented regenerative braking graded energy recovery management and control method and system to solve the problems of low energy recovery efficiency, poor braking smoothness and insufficient fault safety in the existing technology.

[0006] Therefore, the first aspect of this application provides a multiphase motor segmented regenerative braking graded energy recovery management and control method, applied to a vehicle equipped with a dual three-phase motor, wherein the dual three-phase motor has a first set of three-phase windings and a second set of three-phase windings, each set of three-phase windings being driven by an independent power device, the method comprising:

[0007] Acquire vehicle braking status parameters, battery system status parameters, and motor operating status parameters;

[0008] The braking condition type is determined based on the vehicle braking state parameters, and the energy recovery constraints are determined based on the battery system state parameters and the motor operating state parameters.

[0009] Based on the braking condition type and the energy recovery constraint, a target energy recovery level is determined from multiple energy recovery levels, and a winding switching combination method corresponding to the target energy recovery level is determined, wherein each energy recovery level corresponds to a different number of phases selected from the first set of three-phase windings and the second set of three-phase windings;

[0010] Based on the determined winding switching combination, the phase windings in the first set of three-phase windings and the second set of three-phase windings are controlled to be engaged or disengaged to perform regenerative braking energy recovery.

[0011] The above technical solution sets multiple energy recovery levels, each corresponding to a different number of phases selected from the first and second sets of three-phase windings. The target energy recovery level and the corresponding winding switching combination are determined according to the braking condition type and energy recovery constraints. This allows regenerative braking control to select the appropriate number of winding phases to operate under actual conditions. In light recovery conditions, the number of phases can be reduced to lower no-load losses, while in strong recovery conditions, the number of phases can be increased to provide sufficient feedback power. This achieves refined energy recovery management across the entire operating range, improving energy recovery efficiency and braking smoothness.

[0012] Optionally, the plurality of energy recovery levels include a first energy recovery level, a second energy recovery level, a third energy recovery level, and a fourth energy recovery level;

[0013] The winding switching combination method corresponding to the first energy recovery level is to engage the first set of three-phase windings and disconnect the second set of three-phase windings;

[0014] The winding switching combination corresponding to the second energy recovery level is to engage all three phases of the first three-phase winding and two phases of the second three-phase winding;

[0015] The winding switching combination method corresponding to the third energy recovery level is to engage all six phases of the first set of three-phase windings and the second set of three-phase windings;

[0016] The winding switching combination corresponding to the fourth energy recovery level is to cut off all phase windings of the first set of three-phase windings and the second set of three-phase windings.

[0017] The above four energy recovery levels correspond to four different winding phase numbers, enabling regenerative braking control to cover different recovery intensity requirements from single three-phase to full six-phase, achieving fine matching of operating conditions and phase number.

[0018] Optionally, when switching from the current energy recovery level to the target energy recovery level, the number of phases to be engaged can be increased in the order of first engaging the first set of three-phase windings and then engaging the second set of three-phase windings phase by phase, or the number of phases to be engaged can be decreased in the order of first disconnecting the second set of three-phase windings phase by phase and then disconnecting the first set of three-phase windings when exiting energy recovery. After at least one asymmetric intermediate working state, the winding engagement and disengagement combination corresponding to the target energy recovery level can be formed.

[0019] The aforementioned phase-by-phase switching fills the power gap between the full power of a single three-phase system and the minimum power of a six-phase system by forming an asymmetrical intermediate working state (such as four-phase or five-phase), thus avoiding the braking shock caused by hard switching of gears.

[0020] Optionally, determining the target energy recovery level includes:

[0021] When the braking intensity is less than the first intensity threshold, the vehicle speed is in the first vehicle speed range, and the battery state of charge is in the first charge range, the first energy recovery level is determined as the target energy recovery level.

[0022] When the braking intensity is in the second intensity range, the vehicle speed is in the second vehicle speed range, and the battery state of charge is in the second state of charge range, the second energy recovery level is determined as the target energy recovery level.

[0023] When the braking intensity is in the third intensity range, the vehicle speed is in the third vehicle speed range, and the battery state of charge is in the third state of charge range, the third energy recovery level is determined as the target energy recovery level.

[0024] When the shutdown conditions are met, the fourth energy recovery level is determined as the target energy recovery level.

[0025] Optionally, the shutdown conditions include:

[0026] The braking intensity is not less than the emergency braking threshold, emergency braking is triggered, ABS is triggered, the energy recovery switch is manually turned off, or the battery state of charge exceeds the full charge threshold.

[0027] The above-mentioned multi-dimensional coupling parameter determination method comprehensively considers three dimensions: braking intensity, vehicle speed, and battery state of charge, so that the determination of energy recovery level can be adapted to different driving conditions and avoid blind spots in condition coverage caused by single parameter determination.

[0028] Optionally, the method further includes:

[0029] When a single-phase fault is detected in the first set of three-phase windings or the second set of three-phase windings, the faulty phase is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery.

[0030] When a power device fault is detected in the first set of three-phase windings or the second set of three-phase windings, the phase winding corresponding to the faulty power device is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery.

[0031] When a fault is detected in the first set of three-phase windings, the second set of three-phase windings is controlled to perform regenerative braking energy recovery independently.

[0032] When a fault is detected in the second set of three-phase windings, the first set of three-phase windings is controlled to perform regenerative braking energy recovery independently.

[0033] The aforementioned step-by-step degradation fault-tolerant control retains five-phase energy recovery capability when a single phase or power device fails, and retains three-phase energy recovery capability when a single winding fails, thus preventing the instantaneous loss of electric braking force due to the complete withdrawal of regenerative braking.

[0034] A second aspect of this application provides a multiphase motor segmented regenerative braking graded energy recovery management system, applied to a vehicle equipped with a dual three-phase motor. The dual three-phase motor has a first set of three-phase windings and a second set of three-phase windings, each set of three-phase windings being driven by an independent power device. The system includes:

[0035] The parameter acquisition module is used to acquire vehicle braking status parameters, battery system status parameters, and motor operating status parameters;

[0036] Memory, used to store programs;

[0037] A processor is configured to load a program stored in the memory to perform the following operations:

[0038] The braking condition type is determined based on the vehicle braking state parameters, and the energy recovery constraints are determined based on the battery system state parameters and the motor operating state parameters.

[0039] Based on the braking condition type and the energy recovery constraint, a target energy recovery level is determined from multiple energy recovery levels, and a winding switching combination method corresponding to the target energy recovery level is determined, wherein each energy recovery level corresponds to a different number of phases selected from the first set of three-phase windings and the second set of three-phase windings;

[0040] Based on the determined winding switching combination, the phase windings in the first set of three-phase windings and the second set of three-phase windings are controlled to be engaged or disengaged to perform regenerative braking energy recovery.

[0041] Optionally, in the operation performed by the processor, the plurality of energy recovery levels include a first energy recovery level, a second energy recovery level, a third energy recovery level, and a fourth energy recovery level;

[0042] The winding switching combination method corresponding to the first energy recovery level is to engage the first set of three-phase windings and disconnect the second set of three-phase windings;

[0043] The winding switching combination corresponding to the second energy recovery level is to engage all three phases of the first three-phase winding and two phases of the second three-phase winding;

[0044] The winding switching combination method corresponding to the third energy recovery level is to engage all six phases of the first set of three-phase windings and the second set of three-phase windings;

[0045] The winding switching combination corresponding to the fourth energy recovery level is to cut off all phase windings of the first set of three-phase windings and the second set of three-phase windings.

[0046] Optionally, the operations performed by the processor further include:

[0047] When a single-phase fault is detected in the first set of three-phase windings or the second set of three-phase windings, the faulty phase is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery.

[0048] When a power device fault is detected in the first set of three-phase windings or the second set of three-phase windings, the phase winding corresponding to the faulty power device is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery.

[0049] When a fault is detected in the first set of three-phase windings, the second set of three-phase windings is controlled to perform regenerative braking energy recovery independently.

[0050] When a fault is detected in the second set of three-phase windings, the first set of three-phase windings is controlled to perform regenerative braking energy recovery independently.

[0051] A third aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in any one of the first aspects. Attached Figure Description

[0052] Figure 1 A system architecture block diagram of a multiphase motor segmented regenerative braking graded energy recovery management and control system provided in this application embodiment;

[0053] Figure 2This is a schematic diagram of the main flow of a multiphase motor segmented regenerative braking graded energy recovery management and control method provided in an embodiment of this application;

[0054] Figure 3 The flowchart illustrates the hierarchical determination and winding segmentation input logic of a multiphase motor segmented regenerative braking graded energy recovery management and control method provided in this application embodiment. Detailed Implementation

[0055] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more. Furthermore, the use of "based on" or "according to" implies openness and inclusiveness, because processes, steps, calculations, or other actions "based on" or "according to" one or more of the stated conditions or values ​​may in practice be based on additional conditions or beyond the stated values.

[0057] This application provides a multiphase motor segmented regenerative braking graded energy recovery management and control method, applied to vehicles equipped with dual three-phase motors. The dual three-phase motor has a first set of three-phase windings and a second set of three-phase windings, each driven by an independent inverter bridge arm. Hereinafter, winding A represents the first set of three-phase windings (including phase windings U1, V1, and W1), and winding B represents the second set of three-phase windings (including phase windings U2, V2, and W2). The vehicle hardware platform includes: a power battery system (including a battery management system, BMS, monitoring state of charge (SOC), maximum allowable charging current, battery temperature, and bus voltage), a motor drive control system (including a 12-tube IGBT power switch module and a motor controller MCU), a vehicle controller (VCU), a brake pedal, an ABS / EBS braking system, an energy recovery gear switch, and a CAN bus communication network connecting the above components. The VCU, acting as the decision-making layer, sends control commands to the MCU via the CAN bus, and the MCU, acting as the execution layer, controls the power switch module to drive windings A and B.

[0058] The following is combined with Figures 1 to 3 The control flow of the method embodiments of this application will be described in detail in steps S1 to S5.

[0059] S1: Obtain vehicle braking status parameters, battery system status parameters, and motor operating status parameters.

[0060] The VCU collects status parameters from various onboard sensors and subsystems in real time.

[0061] Vehicle braking status parameters include: brake pedal opening s, brake pedal opening change rate ds / dt, vehicle speed V, ABS / EBS braking status signal, and energy recovery level switch signal. Among these, brake pedal opening s is the pedal opening value output by the brake pedal opening sensor, and braking intensity Z is a dimensionless parameter characterizing the degree of vehicle braking demand. The VCU determines the braking intensity Z corresponding to the brake pedal opening s based on a pre-calibrated and stored mapping relationship between brake pedal opening and braking intensity.

[0062] Battery system status parameters are obtained from the BMS via the CAN bus, including: power battery state of charge (SOC), maximum allowable charging current of the battery, battery temperature, and bus voltage.

[0063] The motor operating status parameters are obtained from the MCU via the CAN bus, including: motor speed, rotor position, operating status of each phase of winding A, operating status of each phase of winding B, and winding temperature.

[0064] The above three types of parameters are collected periodically, and the collection period can be set from 10ms to 100ms to balance the real-time performance of operating condition identification and the VCU computing load.

[0065] S2: Determine the braking condition type based on the vehicle braking state parameters, and determine the energy recovery constraints based on the battery system state parameters and motor operating state parameters.

[0066] The VCU analyzes the parameters obtained by S1 to determine the current braking condition type and energy recovery constraints.

[0067] The braking condition type is determined as follows: the VCU identifies the urgency of the braking intention based on the range of braking intensity Z and the brake pedal opening change rate ds / dt. The braking condition types include at least: coasting deceleration condition (Z close to zero, no brake pedal pressed), light braking condition (Z<0.1), moderate braking condition (0.1≤Z<0.4), heavy braking condition (0.4≤Z<0.7), and emergency braking condition (Z≥0.7, or ABS triggered, brake pedal opening change rate ds / dt exceeds the change rate threshold).

[0068] The energy recovery constraints are determined as follows: The VCU assesses the battery's ability to receive charging based on the SOC fed back by the BMS—when the SOC exceeds the upper limit threshold (e.g., 95%), the battery is in a fully charged but limited-charge state; the maximum regenerative power that the battery can withstand is assessed based on the maximum allowable charging current of the battery; and the winding conditions of the motor that can be put into recycling are assessed based on the motor's operating status parameters, including whether the winding temperature is within the normal range and whether there are abnormal conditions such as winding faults or power device faults.

[0069] S3: Based on the braking condition type and energy recovery constraints, determine the target energy recovery level from multiple energy recovery levels, and determine the winding switching combination corresponding to the target energy recovery level.

[0070] Multiple energy recovery levels include a first energy recovery level, a second energy recovery level, a third energy recovery level, and a fourth energy recovery level. Each energy recovery level corresponds to a different number of phases selected from winding A and winding B. The winding switching combinations corresponding to each energy recovery level are shown in the table below:

[0071]

[0072] In one possible implementation, the specific criteria for determining the target energy recovery level are as follows:

[0073] (1) The criteria for determining the first energy recovery level are: braking intensity Z is less than the first intensity threshold (e.g., Z<0.1), vehicle speed V is within the first vehicle speed range (e.g., 10km / h≤V≤40km / h), and battery state of charge (SOC) is within the first charge range (e.g., SOC≤90%). When all three conditions are met, the first energy recovery level is determined as the target energy recovery level. The first energy recovery level is suitable for light recovery conditions during low-speed coasting, and only three phases of winding A are engaged to reduce no-load loss and braking drag.

[0074] (2) The criteria for determining the second energy recovery level are: braking intensity Z is within the second intensity range (e.g., 0.1 ≤ Z < 0.4), vehicle speed V is within the second speed range (e.g., 20 km / h ≤ V ≤ 80 km / h), and battery state of charge (SOC) is within the second charge range (e.g., SOC ≤ 85%). When all three conditions are met simultaneously, the second energy recovery level is determined as the target energy recovery level. The second energy recovery level engages 5 phases (all 3 phases of winding A + 2 phases of winding B) to provide moderate energy recovery.

[0075] (3) The criteria for determining the third energy recovery level are: braking intensity Z is in the third intensity range (e.g., 0.4≤Z<0.7), vehicle speed V is in the third speed range (e.g., V≥40km / h), and battery state of charge (SOC) is in the third charge range (e.g., SOC≤80%). When all three conditions are met, the third energy recovery level is determined as the target energy recovery level. The third energy recovery level engages all 6 phase windings and recovers full power.

[0076] In one possible implementation, a long downhill driving condition serves as another trigger condition for the third energy recovery level. The vehicle control unit (VCU) collects signals from the slope sensor. When it detects that the downhill slope is less than a preset downhill threshold, such as less than -3%, and this state persists for a preset anti-shake time, such as 2 to 3 seconds, it determines that the vehicle is in a long downhill driving condition. When a long downhill driving condition is identified, even if the braking intensity Z does not reach 0.4, as long as the vehicle speed V ≥ 40 km / h and SOC ≤ 80%, the third energy recovery level is still determined as the target energy recovery level.

[0077] (4) The fourth energy recovery level (recovery off) is triggered when the closing conditions are met. The closing conditions include: braking intensity Z reaches or exceeds the emergency braking threshold (e.g., Z≥0.7), emergency braking is triggered (indicated by ABS / ESC signal), ABS is triggered (anti-interference wheel speed stability control), the energy recovery switch is manually turned off, and the battery state of charge (SOC) exceeds the full charge threshold (e.g., SOC>95%). When any of the closing conditions are met, the fourth energy recovery level is determined as the target energy recovery level, all phase windings are locked, regenerative braking is disengaged, and the braking task is handed over to the mechanical braking system.

[0078] During energy recovery, the VCU continuously monitors whether the shut-off conditions are met. When the shut-off conditions are met, it switches to the fourth energy recovery level in real time to ensure that braking safety is prioritized.

[0079] To avoid frequent switching of energy recovery levels due to fluctuations in braking intensity Z around a threshold, the VCU determines the target energy recovery level for three consecutive control cycles, and only performs level switching when the determination results are consistent across the three consecutive control cycles. In one optional implementation, each control cycle T is 100ms, meaning that level switching is performed after the determination results remain consistent for 300ms.

[0080] S4: Based on the determined winding switching combination, control the phase windings in the first set of three-phase windings and the second set of three-phase windings to be engaged or disengaged, and perform regenerative braking energy recovery.

[0081] The VCU sends instructions, including the target energy recovery level, winding switching combination, and corresponding negative torque requirements, to the MCU via the CAN bus. Based on the received instructions, the MCU controls the IGBT power devices in the power switching module to perform switching operations on each phase of winding A and winding B, enabling the motor to enter generator mode. This converts the kinetic energy generated during braking into electrical energy, which is then rectified by the inverter and recharged back into the power battery.

[0082] In one possible implementation, when switching from the current energy recovery level to the target energy recovery level, the MCU does not perform a one-time full-phase switch. When increasing the number of phases engaged, winding A is engaged first, and then phase windings in winding B are engaged one by one according to the operating conditions. When decreasing the number of phases engaged, phase windings in winding B are disconnected one by one, and winding A is disconnected only when energy recovery needs to be discontinued. After at least one asymmetric intermediate working state, the winding engagement / disengagement combination corresponding to the target energy recovery level is formed.

[0083] Taking the switch from the first energy recovery level (3 phases, only winding A) to the third energy recovery level (6 phases, all phases of winding A + winding B) as an example: During the switch, the MCU sequentially puts in the U2 phase, V2 phase, and W2 phase of winding B, and goes through two asymmetric intermediate working states: 4-phase configuration (all 3 phases of winding A + U2 phase of winding B) and 5-phase configuration (all 3 phases of winding A + U2 phase and V2 phase of winding B), and finally reaches the 6-phase full-input configuration.

[0084] Taking the switch from the third energy recovery level (6 phases) to the first energy recovery level (3 phases) as an example: During the switch, the MCU sequentially cuts off the W2 phase, V2 phase and U2 phase of winding B, and experiences two asymmetric intermediate working states of 5 phases and 4 phases respectively, and finally reaches the 3-phase configuration.

[0085] The phase-by-phase switching method described above fills the power gap between the full power of a single three-phase circuit and the minimum power of a six-phase circuit, avoiding the braking torque step shock caused by hard switching between different levels and improving braking smoothness. The time interval between each single-phase connection or disconnection can be set according to the response characteristics of the power switching module, for example, from 5ms to 50ms.

[0086] When the target energy recovery level is the fourth energy recovery level (recovery off), the MCU blocks the drive signals of all power devices, causing all phase windings of winding A and winding B to exit the regenerative braking working state.

[0087] S5: Fault-tolerant control

[0088] The method in this application embodiment also includes fault-tolerant control logic. When a winding or power device fault is detected, the system automatically downgrades to the recovery capacity level corresponding to the number of remaining intact phases. Fault detection is achieved through real-time monitoring of the current of each phase, the temperature of each IGBT power device, and the winding temperature by the MCU.

[0089] In one possible implementation, fault-tolerant control is executed according to the following cascading chain:

[0090] (1) When a single-phase fault (such as an open circuit or short circuit in a certain phase winding) is detected in winding A or winding B, the IGBT drive signal corresponding to the fault is blocked, and the remaining intact phase windings (5 phases) are controlled to perform regenerative braking energy recovery.

[0091] (2) When a power device fault (such as overheating or breakdown of a phase IGBT) is detected in winding A or winding B, the phase winding corresponding to the faulty power device is blocked, and the remaining intact phase winding is controlled to perform regenerative braking energy recovery.

[0092] (3) When a fault is detected in the entire winding A (such as a simultaneous fault in multiple phases of winding A or a complete failure of inverter arm A), all three phases of winding A are blocked, and winding B is controlled to perform regenerative braking energy recovery in three phases alone. When at least two phases of winding A fail simultaneously, the entire winding A is directly determined to be faulty, and the four-phase asymmetrical operation mode consisting of the remaining phase of winding A and the three phases of winding B is not adopted. When at least two phases of winding B fail simultaneously, the same processing logic is adopted.

[0093] (4) When a fault is detected in the entire winding B, all three phases of winding B are blocked, and winding A is controlled to perform regenerative braking energy recovery in three phases alone.

[0094] (5) When an extreme fault is detected (such as an unrecoverable fault occurring simultaneously in winding A and winding B, or an abnormal bus voltage, or an abnormal MCU self-test), all windings are locked and regenerative braking is disengaged.

[0095] When at least one phase of winding A and winding B fails, since there is no complete and intact three-phase winding, the system locks up both windings, exits the four-phase asymmetrical working mode, and shuts down regenerative braking. The braking force is provided by the mechanical braking system, and the corresponding fault diagnosis code is reported at the same time.

[0096] The aforementioned phase winding fault is a permanent hardware fault. While the fault flag remains active, the faulty phase remains blocked and will not be automatically reconnected.

[0097] This application also provides a multiphase motor segmented regenerative braking graded energy recovery management system. This system is applied to vehicles equipped with dual three-phase motors, which have a first set of three-phase windings (winding A) and a second set of three-phase windings (winding B).

[0098] The system includes a parameter acquisition module, memory, and processor.

[0099] The parameter acquisition module is used to acquire vehicle braking status parameters, battery system status parameters, and motor operating status parameters. Integrated into the vehicle control unit (VCU), the module communicates with the brake pedal sensor, BMS, MCU, ABS / ESC controller, and energy recovery mode switch via a CAN bus interface to acquire brake pedal opening degree (s), brake pedal opening change rate (ds / dt), vehicle speed (V), ABS / ESC braking status, energy recovery mode signal, battery SOC, maximum allowable battery charging current, battery temperature, bus voltage, motor speed, rotor position, phase operating status, and winding temperature. This module corresponds to the execution entity of step S1 in the above method embodiment.

[0100] The memory is used to store programs. The memory is a non-volatile storage medium built into the VCU (such as Flash memory), which stores the energy recovery classification determination program, the winding segment switching control program, and the fault tolerance control program.

[0101] The processor loads programs stored in memory to perform the following operations:

[0102] The braking condition type is determined based on the vehicle braking state parameters, and the energy recovery constraints are determined based on the battery system state parameters and the motor operating state parameters.

[0103] Based on the braking condition type and energy recovery constraints, a target energy recovery level is determined from multiple energy recovery levels, and the winding switching combination corresponding to the target energy recovery level is determined. Each energy recovery level corresponds to a different number of phases selected from the first set of three-phase windings and the second set of three-phase windings.

[0104] Based on the determined winding switching combination, the phase windings in the first set of three-phase windings and the second set of three-phase windings are controlled to be engaged or disengaged to perform regenerative braking energy recovery.

[0105] The three operations performed by the processor correspond to the execution entities of steps S2, S3, and S4 in the above method embodiments.

[0106] In one possible implementation, the processor performs operations with multiple energy recovery levels including a first energy recovery level, a second energy recovery level, a third energy recovery level, and a fourth energy recovery level. The winding switching combination corresponding to the first energy recovery level is to engage the first set of three-phase windings and disconnect the second set of three-phase windings. The winding switching combination corresponding to the second energy recovery level is to engage all three phases of the first set of three-phase windings and two phases of the second set of three-phase windings. The winding switching combination corresponding to the third energy recovery level is to engage all six phases of the first set of three-phase windings and the second set of three-phase windings. The winding switching combination corresponding to the fourth energy recovery level is to disconnect all phases of the first set of three-phase windings and the second set of three-phase windings. This operation corresponds to the definition of the correspondence between energy recovery levels and winding switching combinations in step S3 of the above method embodiment.

[0107] In one possible implementation, the operations performed by the processor further include fault-tolerant control operations: when a single-phase fault is detected in the first or second three-phase winding, the faulty phase is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery; when a power device fault is detected in the first or second three-phase winding, the phase winding corresponding to the faulty power device is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery; when a complete fault is detected in the first three-phase winding, the second three-phase winding is controlled to perform regenerative braking energy recovery independently; when a complete fault is detected in the second three-phase winding, the first three-phase winding is controlled to perform regenerative braking energy recovery independently. This operation corresponds to the execution body of step S5 in the above method embodiment.

[0108] This application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, it implements steps S1 to S5 in the above method embodiments. The storage medium can be any one of VCU built-in Flash, external SD card, USB storage device, or cloud OTA upgrade server.

[0109] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions within the technical scope disclosed in the present invention should be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for segmented regenerative braking and graded energy recovery management and control of a multiphase motor, characterized in that, Applied to vehicles equipped with dual three-phase motors, the dual three-phase motors having a first set of three-phase windings and a second set of three-phase windings, each set of three-phase windings being driven by an independent power device, the method includes: Acquire vehicle braking status parameters, battery system status parameters, and motor operating status parameters; The braking condition type is determined based on the vehicle braking state parameters, and the energy recovery constraints are determined based on the battery system state parameters and the motor operating state parameters. Based on the braking condition type and the energy recovery constraint, a target energy recovery level is determined from multiple energy recovery levels, and a winding switching combination method corresponding to the target energy recovery level is determined, wherein each energy recovery level corresponds to a different number of phases selected from the first set of three-phase windings and the second set of three-phase windings; Based on the determined winding switching combination, the phase windings in the first set of three-phase windings and the second set of three-phase windings are controlled to be engaged or disengaged to perform regenerative braking energy recovery.

2. The method according to claim 1, characterized in that, The multiple energy recovery levels include a first energy recovery level, a second energy recovery level, a third energy recovery level, and a fourth energy recovery level; The winding switching combination method corresponding to the first energy recovery level is to engage the first set of three-phase windings and disconnect the second set of three-phase windings; The winding switching combination corresponding to the second energy recovery level is to engage all three phases of the first three-phase winding and two phases of the second three-phase winding; The winding switching combination method corresponding to the third energy recovery level is to engage all six phases of the first set of three-phase windings and the second set of three-phase windings; The winding switching combination corresponding to the fourth energy recovery level is to cut off all phase windings of the first set of three-phase windings and the second set of three-phase windings.

3. The method according to claim 2, characterized in that, The step of controlling the engagement or disengagement of phase windings in the first set of three-phase windings and the second set of three-phase windings according to the determined winding engagement / disengagement combination to perform regenerative braking energy recovery includes: When switching to the target energy recovery level, the number of phases to be engaged is increased in the order of first engaging the first set of three-phase windings and then engaging the second set of three-phase windings phase by phase, or the number of phases to be engaged is decreased in the order of first disconnecting the second set of three-phase windings phase by phase and then disconnecting the first set of three-phase windings when exiting energy recovery, thus forming the winding engagement and disengagement combination method corresponding to the target energy recovery level.

4. The method according to claim 2, characterized in that, Determining the target energy recovery level includes: When the braking intensity is less than the first intensity threshold, the vehicle speed is in the first vehicle speed range, and the battery state of charge is in the first charge range, the first energy recovery level is determined as the target energy recovery level. When the braking intensity is in the second intensity range, the vehicle speed is in the second vehicle speed range, and the battery state of charge is in the second state of charge range, the second energy recovery level is determined as the target energy recovery level. When the braking intensity is in the third intensity range, the vehicle speed is in the third vehicle speed range, and the battery state of charge is in the third state of charge range, the third energy recovery level is determined as the target energy recovery level. When the shutdown conditions are met, the fourth energy recovery level is determined as the target energy recovery level.

5. The method according to claim 4, characterized in that, The shutdown conditions include: The braking intensity is not less than the emergency braking threshold, emergency braking is triggered, ABS is triggered, the energy recovery switch is manually turned off, or the battery state of charge exceeds the full charge threshold.

6. The method according to claim 1, characterized in that, The method further includes: When a single-phase fault is detected in the first set of three-phase windings or the second set of three-phase windings, the faulty phase is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery. When a power device fault is detected in the first set of three-phase windings or the second set of three-phase windings, the phase winding corresponding to the faulty power device is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery. When a fault is detected in the first set of three-phase windings, the second set of three-phase windings is controlled to perform regenerative braking energy recovery independently. When a fault is detected in the second set of three-phase windings, the first set of three-phase windings is controlled to perform regenerative braking energy recovery independently. Specifically, when at least two phases of the same three-phase winding fail, the entire three-phase winding is determined to be faulty, and another three-phase winding is controlled to perform regenerative braking energy recovery independently; when at least one phase of the first three-phase winding and the second three-phase winding fail, both three-phase windings are locked, regenerative braking is turned off, and a fault diagnostic code is reported; the faulty phase winding remains locked while the fault mark persists.

7. A multiphase motor segmented regenerative braking graded energy recovery management system, characterized in that, An application to vehicles equipped with dual three-phase motors, wherein the dual three-phase motors have a first set of three-phase windings and a second set of three-phase windings; each set of three-phase windings is driven by an independent power device, the system comprising: The parameter acquisition module is used to acquire vehicle braking status parameters, battery system status parameters, and motor operating status parameters. Memory, used to store programs; A processor is configured to load a program stored in the memory to perform the following operations: The braking condition type is determined based on the vehicle braking state parameters, and the energy recovery constraints are determined based on the battery system state parameters and the motor operating state parameters. Based on the braking condition type and the energy recovery constraint, a target energy recovery level is determined from multiple energy recovery levels, and a winding switching combination method corresponding to the target energy recovery level is determined, wherein each energy recovery level corresponds to a different number of phases selected from the first set of three-phase windings and the second set of three-phase windings; Based on the determined winding switching combination, the phase windings in the first set of three-phase windings and the second set of three-phase windings are controlled to be engaged or disengaged to perform regenerative braking energy recovery.

8. The system according to claim 7, characterized in that, In the operation performed by the processor, the plurality of energy recovery levels include a first energy recovery level, a second energy recovery level, a third energy recovery level, and a fourth energy recovery level; The winding switching combination method corresponding to the first energy recovery level is to engage the first set of three-phase windings and disconnect the second set of three-phase windings; The winding switching combination corresponding to the second energy recovery level is to engage all three phases of the first three-phase winding and two phases of the second three-phase winding; The winding switching combination method corresponding to the third energy recovery level is to engage all six phases of the first set of three-phase windings and the second set of three-phase windings; The winding switching combination corresponding to the fourth energy recovery level is to cut off all phase windings of the first set of three-phase windings and the second set of three-phase windings.

9. The system according to claim 7, characterized in that, The operations that the processor performs also include: When a single-phase fault is detected in the first set of three-phase windings or the second set of three-phase windings, the faulty phase is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery. When a power device fault is detected in the first set of three-phase windings or the second set of three-phase windings, the phase winding corresponding to the faulty power device is blocked, and the remaining intact phase windings are controlled to perform regenerative braking energy recovery. When a fault is detected in the first set of three-phase windings, the second set of three-phase windings is controlled to perform regenerative braking energy recovery independently. When a fault is detected in the second set of three-phase windings, the first set of three-phase windings is controlled to perform regenerative braking energy recovery independently.

10. A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method of any one of claims 1 to 6.

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