Discharge control method and device of multi-motor system and storage medium

Abstract

The invention provides a discharge control method and device for a multi-motor system and a storage medium, and relates to the technical field of hybrid vehicle control, and the method comprises the steps: judging whether a first motor subsystem and a second motor subsystem have a fault of prohibiting active discharge or not; if the faults exist in the first motor subsystem and the second motor subsystem, a passive discharging process is executed; if one of the first motor subsystem and the second motor subsystem has no fault and the other has the fault, executing a single-motor active discharge process; and if neither the first motor subsystem nor the second motor subsystem has the fault, executing a dual-motor cooperative active discharge process. According to the method, a multi-mode discharging mechanism is provided for a multi-motor scene, active discharging of a system level is completed through cooperation of all motor subsystems, high-voltage safety of the whole vehicle is guaranteed, and shaking of the whole vehicle is restrained to a certain degree.

Description

Technical Field

[0001] This disclosure belongs to the field of hybrid vehicle control technology, specifically relating to a discharge control method, device and storage medium for a multi-motor system. Background Technology

[0002] In hybrid vehicles with multi-motor systems, current multi-motor systems mostly involve individual motor subsystems actively discharging, rather than the entire hybrid powertrain system working together to achieve system-level active discharging. For example... Figure 1 The multi-motor system shown has ISG motor subsystem and MT motor subsystem discharging independently. ISG motor 3 is directly connected to engine 1, and MT motor subsystem 5 is connected after clutch 7 and before gearbox 8.

[0003] In related technologies, due to the lack of a system-level coordinated discharge mechanism, when the active discharge function of a single motor subsystem fails, it is impossible to effectively perform active discharge through another single motor subsystem, thus creating a high-voltage safety risk. Summary of the Invention

[0004] This disclosure provides a discharge control method, device, and storage medium for a multi-motor system, aiming to at least partially solve the technical problem of high-voltage safety risks caused by the lack of a system-level coordinated discharge mechanism in related technologies' discharge strategies.

[0005] At least one embodiment of this disclosure provides a discharge control method for a multi-motor system, applied to a multi-motor system having a first motor subsystem and a second motor subsystem, including: Determine whether each of the first motor subsystem and the second motor subsystem has a fault that prevents active discharge; If both the first motor subsystem and the second motor subsystem have a fault that prevents active discharge, a passive discharge procedure is executed so that both the first motor subsystem and the second motor subsystem are passively discharged. If one of the first motor subsystem and the second motor subsystem is fault-free and the other both have a fault that prohibits active discharge, execute the single-motor active discharge procedure to allow the fault-free motor subsystem to actively discharge; and, If neither the first motor subsystem nor the second motor subsystem has a fault that prohibits active discharge, the dual-motor coordinated active discharge process is executed so that the first motor subsystem and the second motor subsystem discharge together.

[0006] The above solution offers the following technical advantages: It proposes a discharge control method suitable for multi-motor systems. This method, based on intelligent system state judgment and a multi-mode discharge mechanism, effectively improves the safety and reliability of hybrid vehicles during the discharge process. When the multi-motor system needs to discharge, it first monitors and determines in real time whether either of the two motor subsystems has a fault that prohibits active discharge. If both systems have such a fault, it automatically switches to passive discharge mode, consuming excess energy through the passive discharge process to avoid system risks. If one of the motor subsystems is fault-free, it independently performs the active discharge task, ensuring rapid discharge while significantly reducing the impact on the entire vehicle system. If neither system detects a fault, a cooperative discharge strategy is adopted, with the main control unit coordinating the two motor subsystems to jointly perform the discharge operation, improving discharge efficiency while ensuring torque balance and system stability. This method not only effectively solves the problem of high-voltage safety risks caused by the inability to effectively perform active discharge due to the failure of one motor system in a hybrid system, but also avoids the problem of vehicle vibration caused by unexpected torque during active discharge due to incomplete motor decoupling or system abnormalities through intelligent discharge mechanism, which significantly improves the robustness of the system and the overall driving quality of the vehicle.

[0007] The method provided in at least one embodiment of this disclosure further includes: Determine whether the multi-motor system has a discharge requirement; and, When the multi-motor system has a discharge requirement, a control command is generated to determine whether the first motor subsystem and the second motor subsystem each have a fault that prohibits active discharge, so as to start the discharge control of the multi-motor system.

[0008] The above solution has the following technical effects: automatic start-up of discharge control for multi-motor systems.

[0009] The method provided in at least one embodiment of this disclosure further includes: When the multi-motor system has a discharge requirement, the health status of the first motor subsystem and the second motor subsystem is detected; and... The health status parameters of the first motor subsystem and the second motor subsystem in the detection results are obtained, and the first motor subsystem and the second motor subsystem are judged based on the health status parameters to determine whether each of them has a fault that prohibits active discharge.

[0010] The above scheme has the following technical effects: it starts the discharge control of the multi-motor system based on the health status of the first motor subsystem and the second motor subsystem.

[0011] In at least one embodiment of the method provided in this disclosure, the fault preventing active discharge includes: The first type of fault is a motor controller malfunction caused by a hardware or software failure of the motor controller itself in the first or second motor subsystem; and... The second type of fault is a motor runaway fault caused by an abnormality in the motor body of the first motor subsystem or the second motor subsystem.

[0012] The above solution has the following technical effects: accurately locating the fault type that prevents active discharge.

[0013] In at least one embodiment of the method provided in this disclosure, the single-motor active discharge process includes: Identify the fault-free motor subsystems in the first and second motor subsystems; The active discharge timeout fault threshold of the fault-free motor subsystem is extended from the initial first threshold to a second threshold, wherein the second threshold is greater than the first threshold; Send an active discharge command to the fault-free motor subsystem so that it discharges independently; During the discharge process, the bus voltage of the multi-motor system is monitored; and, If the bus voltage drops below the safe voltage threshold within the discharge time corresponding to the second threshold, the multi-motor system is determined to have completed discharging.

[0014] The above solution has the following technical effects: if there is only one normal motor subsystem, the normal motor subsystem will perform active discharge and extend the active discharge timeout fault threshold to exceed the conventional limit to avoid interruption due to timeout.

[0015] In at least one embodiment of the method provided in this disclosure, the multi-motor system further includes an engine directly connected to the first motor subsystem and a clutch disposed between the first motor subsystem and the second motor subsystem, and the dual-motor cooperative active discharge process includes: Determine whether the clutch is in a disengaged state; When the clutch is disengaged, a first cooperative discharge strategy is executed, such that the multi-motor system preferentially performs active discharge by the first motor subsystem, and when the discharge capacity of the first motor subsystem is insufficient, the second motor subsystem is awakened to synchronously perform active discharge; and When the clutch is in the non-disengaged state, a second cooperative discharge strategy is executed so that the first motor subsystem and the second motor subsystem actively discharge together.

[0016] The above solution offers the following technical advantages: When both motor subsystems are functioning normally, a suitable discharge strategy is selected based on the clutch status. In the clutch-engaged state, both systems discharge synchronously to improve efficiency. In the disengaged state, the first motor subsystem, acting as the main motor, prioritizes discharge. If the timeout occurs, the backup motor is automatically activated for coordinated operation. When the drive motor actively discharges, uncertainties such as poor tuning, motor aging, or malfunctions may generate torque that causes vehicle vibration. The above solution, in both engaged and disengaged states, prioritizes the first motor subsystem, directly connected to the engine, to perform the active discharge strategy, effectively avoiding vehicle vibration.

[0017] In at least one embodiment of the method provided in this disclosure, the first cooperative discharge strategy includes: The active discharge timeout fault threshold of the first motor subsystem is extended from the first threshold to a third threshold that is different from the second threshold, wherein the third threshold is greater than the first threshold and less than the second threshold; Send an active discharge command to the first motor subsystem so that the first motor subsystem discharges independently; During the discharge process, the bus voltage of the multi-motor system is monitored; Determine whether the bus voltage drops below the safe voltage threshold within the discharge time corresponding to the third threshold. If so, the active discharge is deemed complete; and, If not, it is determined that the discharge capability of the first motor subsystem is insufficient, the second motor subsystem is woken up, and an active discharge command is sent to the second motor subsystem so that the first motor subsystem and the second motor subsystem can actively discharge synchronously.

[0018] The above solution has the following technical effects: it takes into account the active discharge condition of multi-motor systems. When the clutch is disengaged, the active discharge timeout fault threshold of the first motor subsystem is adjusted to avoid discharge interruption and ensure high voltage safety.

[0019] In at least one embodiment of the method provided in this disclosure, the second cooperative discharge strategy includes: Send an active discharge command to the first motor subsystem and the second motor subsystem so that the first motor subsystem and the second motor subsystem start up synchronously and discharge together. During the discharge process, the bus voltage of the multi-motor system is monitored; Determine whether the bus voltage drops below the safe voltage threshold within the discharge time corresponding to the first threshold. If so, the discharge is considered complete; and, If not, trigger a discharge timeout fault alarm.

[0020] The above solution has the following technical effect: it improves the discharge efficiency of multi-motor systems.

[0021] At least one embodiment of this disclosure also provides a discharge control device for a multi-motor system, applied to a multi-motor system having a first motor subsystem and a second motor subsystem, including: The preprocessing unit is configured to determine whether each of the first motor subsystem and the second motor subsystem has a fault that prohibits active discharge; The first control unit is configured to execute a passive discharge process if both the first motor subsystem and the second motor subsystem have a fault that prevents active discharge, so that both the first motor subsystem and the second motor subsystem are passively discharged. The second control unit is configured to execute a single-motor active discharge procedure if one of the first motor subsystem and the second motor subsystem is fault-free and the other has a fault that prohibits active discharge, so that the fault-free motor subsystem actively discharges; and, The third control unit is configured to execute a dual-motor coordinated active discharge process if neither the first motor subsystem nor the second motor subsystem has a fault that prohibits active discharge, so that the first motor subsystem and the second motor subsystem discharge together.

[0022] At least one embodiment of this disclosure also provides a storage medium storing a program or instructions, wherein the program or instructions, when executed by a processor, implement the steps of the method provided in any embodiment of this disclosure.

[0023] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a structural diagram of a hybrid powertrain that includes a multi-motor system; Figure 2 A flowchart of a discharge control method for a multi-motor system provided in at least one embodiment of this disclosure; Figure 3 A flowchart of another discharge control method for a multi-motor system provided in at least one embodiment of this disclosure; Figure 4A flowchart of a discharge control method for a multi-motor system provided in at least one embodiment of this disclosure; Figure 5 A flowchart of active discharge of a single motor provided for at least one embodiment of this disclosure; Figure 6 A flowchart of dual-motor active discharge provided for at least one embodiment of this disclosure; Figure 7 Example flowchart of a discharge control method for a multi-motor system provided in at least one embodiment of this disclosure; Figure 8 A structural block diagram of a discharge control device for a multi-motor system provided in at least one embodiment of this disclosure; Figure 9 A schematic diagram illustrating the composition of a program product provided for at least one embodiment of this disclosure.

[0026] Figure label: 1- Engine; 2- Vehicle controller; 3- ISG motor; 4- ISG motor controller; 5- MT motor; 6- MT motor controller; 7- Clutch; 8- Gearbox; 9- Power battery; 10- Discharge control equipment for multi-motor system; 11- Pre-processing unit; 12- First control unit; 13- Second control unit; 14- Third control unit; 21- Processor; 22- Memory; 23- Input device; 24- Output device. Detailed Implementation

[0027] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be particularly noted that the following embodiments are for illustrative purposes only and do not limit the scope of the disclosure. Similarly, the following embodiments are only some, not all, embodiments of the present disclosure, and all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0028] The terms "first," "second," and "third" used in the embodiments of this disclosure are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first," "second," and "third" may explicitly or implicitly include at least one of that feature.

[0029] In the description of this disclosure, "multiple" means at least two, such as two or three, unless otherwise expressly and specifically limited.

[0030] In this disclosure, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0031] The terms “comprising” and “having”, and any variations thereof, used in this disclosure are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or components inherent to such processes, methods, products, or devices.

[0032] In the embodiments of this disclosure, the term "passive discharge" refers to the process in which the DC bus capacitor discharges without the drive motor controller actively initiating the discharge mechanism after the DC bus power supply is cut off.

[0033] In this disclosure, the term "active discharge" refers to the process by which the drive motor controller actively initiates a discharge mechanism and the DC bus capacitor actively discharges after the DC bus power supply is disconnected. The national standard GB / T18488 requires that the time taken for the bus capacitor to discharge to 60V should not exceed 3 seconds.

[0034] In the embodiments of this disclosure, the term "motor subsystem" includes both the motor and the motor controller.

[0035] In this disclosure, the term "ISG motor" refers to an integrated starter-generator motor that is combined between the engine and the clutch, serving the functions of starting the engine and generating electricity by recovering braking energy.

[0036] In this disclosure, the term "MT motor" refers to a drive motor used to drive the vehicle, specifically a starter-generator integrated motor that is located between the clutch and the transmission.

[0037] Figure 2 This is a flowchart illustrating a discharge control method for a multi-motor system, provided in at least one embodiment of the present disclosure. The multi-motor system includes a first motor subsystem and a second motor subsystem, both of which can perform drive and braking energy recovery. Specific actions are decided by the system controller. Figure 2As shown, the method may include the following steps S10-S40.

[0038] Step S10: Determine whether the first motor subsystem and the second motor subsystem each have a fault that prevents active discharge.

[0039] Step S20: If both the first motor subsystem and the second motor subsystem have a fault that prohibits active discharge, execute the passive discharge process so that both the first motor subsystem and the second motor subsystem are passively discharged.

[0040] Step S30: If one of the first motor subsystem and the second motor subsystem is fault-free and the other has a fault that prohibits active discharge, execute the single motor active discharge process so that the fault-free motor subsystem can actively discharge.

[0041] Step S40: If neither the first motor subsystem nor the second motor subsystem has a fault that prohibits active discharge, execute the dual-motor coordinated active discharge process so that the first motor subsystem and the second motor subsystem discharge together.

[0042] It should be noted that this disclosure does not limit the types of motors in the first and second motor subsystems. The active discharge releases the charge in the capacitor of the motor controller within the motor subsystem.

[0043] During implementation, if one of the motor subsystems in the first motor subsystem and the second motor subsystem fails while the other motor subsystem is normal, active discharge can continue to be performed through the other subsystem until the active discharge is completed.

[0044] In the above scheme, this disclosure does not limit the judgment scheme in step S10. In practical application scenarios, for example, the vehicle controller collects fault diagnosis messages from the first motor subsystem and the second motor subsystem in real time, and performs the judgment in step S10 in combination with preset fault judgment rules. The fault judgment rules can cover fault types that prohibit active discharge, such as excessive capacitor voltage inside the motor controller, overheat protection triggering of the drive module, and abnormal communication protocol; when the vehicle controller receives any of the above-mentioned fault signals reported by the motor subsystem, it determines that the subsystem has a fault that prohibits active discharge, otherwise it determines that there is no such fault. In some scenarios, a redundancy verification mechanism can also be introduced, such as comparing fault signals collected by dual sensors or cross-controller fault information interaction verification, to reduce the risk of misjudgment caused by a single signal anomaly and ensure the accuracy and safety of subsequent discharge strategy selection.

[0045] When the system executes step S10, it can select an appropriate judgment scheme according to the actual application scenario.

[0046] In the above scheme, this disclosure does not limit the passive discharge process in step S20. In practical application scenarios, when two motor subsystems are determined to have a fault that prohibits active discharge, the vehicle controller can send a passive discharge start signal to the motor controller of the subsystem; after receiving the signal, the motor controller closes the control switch of the passive discharge circuit and releases energy to the high-voltage bus capacitor using the built-in bleeder resistor. The vehicle controller needs to continuously monitor the bus voltage value of the subsystem. When the voltage drops to a preset safety threshold, it confirms that the passive discharge is complete and sends a stop command to the motor controller to disconnect the passive discharge circuit. If both subsystems in the multi-motor system meet the passive discharge conditions, the vehicle controller can issue passive discharge commands to the two subsystems respectively, independently control their respective passive discharge processes, and simultaneously monitor the voltage status of the two systems in parallel to ensure that all high-voltage components reach the safe voltage range.

[0047] When the system executes step S20, if there is a fault that prohibits active discharge in both subsystems, then the first motor subsystem and the second motor subsystem are passively discharged to achieve coordinated safe discharge of the multi-motor system.

[0048] In the above scheme, this disclosure does not limit the single-motor active discharge process in step S30. In practical application scenarios, in addition to the scheme described in the following embodiments, the single-motor active discharge process can also dynamically optimize the discharge strategy according to the real-time operating parameters of the motor subsystem: the fault-free motor subsystem can dynamically adjust the active discharge power based on the real-time bus voltage, motor winding temperature and current load status. For example, when the motor winding temperature is close to the preset overheat protection threshold, the vehicle controller can actively reduce the active discharge power output of the subsystem to avoid damage to the motor components due to continuous high temperature; if the bus voltage is much higher than the safety threshold and the motor is currently unloaded or has a very low load, the discharge power can be appropriately increased to accelerate the discharge process and shorten the time for the system to enter a safe state.

[0049] When the system executes step S30, it can select a suitable single-motor active discharge process according to the actual application scenario.

[0050] In the above scheme, this disclosure does not limit the dual-motor cooperative active discharge process in step S40. In practical application scenarios, in addition to the scheme described in the following embodiments, the dual-motor cooperative active discharge process can also dynamically optimize the discharge strategy according to the cooperative operation status of the multi-motor subsystem. For example, when there is a significant difference in the bus voltage of the two motor subsystems, the vehicle controller can allocate a higher active discharge power weight to the subsystem with higher voltage, while reducing the discharge power of the subsystem with lower voltage, so as to achieve a balanced decrease in the bus voltage of the two systems and avoid over-discharge of a single system; if one of the motor subsystems experiences a temporary power output limitation, such as a safety constraint caused by abnormal sensor signal, the other normal subsystem can temporarily undertake more active discharge tasks to ensure that the overall discharge process proceeds as expected; in addition, in the dual-motor cooperative active discharge process, the vehicle controller can also dynamically adjust the start and stop timing of active discharge based on the battery remaining charge status fed back by the battery management system. When the battery remaining charge has dropped to a safe range and the bus voltage is stable below the threshold, the active discharge process can be terminated in advance to reduce unnecessary energy consumption. These differentiated optimization strategies can cover more complex real-world application scenarios and improve the flexibility and adaptability of discharge control in multi-motor systems.

[0051] When the system executes step S40, it can select a suitable dual-motor cooperative active discharge process according to the actual application scenario.

[0052] Through steps S10-S40, a discharge control method suitable for multi-motor systems is proposed. This method, based on intelligent system state judgment and a multi-mode discharge mechanism, effectively improves the safety and reliability of hybrid vehicles during the discharge process. When the multi-motor system needs to discharge, it first monitors and judges in real time whether there is a fault that prohibits active discharge in both motor subsystems. If such a fault is detected in both systems, it automatically switches to passive discharge mode, consuming excess energy through the passive discharge process and avoiding system risks. If one of the motor subsystems is fault-free, it independently performs the active discharge task, ensuring rapid discharge while significantly reducing the impact on the entire vehicle system. If no fault is detected in either system, a cooperative discharge strategy is adopted, with the main control unit coordinating the two motor subsystems to jointly perform the discharge operation, improving discharge efficiency while ensuring torque balance and system stability. This method not only effectively solves the problem of high-voltage safety risks caused by the inability to effectively perform active discharge due to the failure of one motor system in a hybrid system, but also avoids the problem of vehicle vibration caused by unexpected torque during active discharge due to incomplete motor decoupling or system abnormalities through intelligent discharge mechanism, which significantly improves the robustness of the system and the overall driving quality of the vehicle.

[0053] Some embodiments of this disclosure also provide systems, storage media, and program products corresponding to the methods described above.

[0054] The method provided in at least one embodiment of this disclosure is applicable to any existing multi-motor system discharge control application scenario. For example, in the dual-motor powertrain scenario of a hybrid electric vehicle, when the high-voltage energy storage system needs to be discharged after the vehicle decelerates and coasts or recovers braking energy, this method can intelligently switch between passive discharge mode, single-motor active discharge mode, or dual-motor cooperative discharge mode based on the real-time fault detection results of the two motor subsystems. As another example, in the distributed multi-motor drive system of a pure electric heavy-duty truck, when the remaining high-voltage electrical energy needs to be safely released after the vehicle stops to meet maintenance requirements, this method can effectively coordinate the discharge actions of each motor subsystem, balancing discharge efficiency and system operational stability. Furthermore, in the multi-motor cooperative operation system of new energy engineering machinery, when the excess electrical energy of the energy storage unit needs to be quickly released after the equipment stops operating to ensure operational safety, this method can flexibly adapt to the health status of different motor subsystems and select the preferred discharge mode to perform the corresponding operation.

[0055] In some embodiments, Figure 2 Based on this, the first motor subsystem is the ISG motor subsystem, and the second motor subsystem is the MT motor subsystem. The ISG motor subsystem is directly connected to the engine, while the MT motor subsystem is located after the clutch and before the transmission. The ISG motor subsystem can utilize the engine's rotational inertia to assist in the active discharge process. When the vehicle controller determines that the ISG motor subsystem is fault-free, it can maintain a stable low engine speed, driving the ISG motor to operate in generator mode, converting the electrical energy from the high-voltage energy storage system into mechanical energy and consuming it through the engine load. The MT motor subsystem, taking advantage of its position in the drivetrain, can independently perform active discharge when the clutch is disengaged, or discharge in coordination with the ISG motor subsystem when the clutch is engaged, controlling the discharge power by adjusting the speed of the transmission input shaft. This structural layout allows the multi-motor system to flexibly switch operating modes during discharge, meeting the discharge requirements under different fault conditions while optimizing discharge efficiency and system stability through coordinated control.

[0056] Figure 3 A flowchart illustrating another discharge control method for a multi-motor system provided in at least one embodiment of this disclosure. Figure 2 Based on this, in order to automatically start the discharge control of the multi-motor system, such as Figure 3 As shown, the method further includes the following steps S01-S02.

[0057] Step S01: Determine if the multi-motor system has a discharge requirement.

[0058] Step S02: When the multi-motor system has a discharge requirement, a control command is generated to determine whether the first motor subsystem and the second motor subsystem each have a fault that prohibits active discharge, so as to start the discharge control of the multi-motor system.

[0059] The control commands will be sent to the local controllers of the first and second motor subsystems, triggering each subsystem to execute a fault detection process and feeding the detection results back to the vehicle controller. These detection results will serve as the core basis for subsequently selecting between passive discharge mode, single-motor active discharge mode, or dual-motor cooperative discharge mode, ensuring that discharge control is executed efficiently while meeting safety requirements.

[0060] Figure 4 This is a flowchart illustrating a discharge control method for a multi-motor system provided in at least one embodiment of the present disclosure. Figure 2 or Figure 3 Based on this, in order to automatically start the discharge control of the multi-motor system, such as Figure 4 As shown, the method further includes the following steps S03-S04.

[0061] Step S03: When there is a discharge requirement in the multi-motor system, check the health status of the first motor subsystem and the second motor subsystem.

[0062] Step S04: Obtain the health status parameters of the first motor subsystem and the second motor subsystem from the detection results, and determine whether the first motor subsystem and the second motor subsystem have a fault that prohibits active discharge based on the health status parameters.

[0063] When a multi-motor system requires discharge, the health status of the two motor subsystems is first checked. If both motor subsystems have discharge limitation faults, a passive discharge process is initiated to enter passive discharge mode. If only one motor subsystem is normal, the normal motor subsystem performs active discharge to enter single active discharge mode. If both motor subsystems are normal, a dual-motor cooperative active discharge mode is entered.

[0064] In some embodiments, Figure 4Based on this, to accurately initiate the corresponding discharge mode, the faults that prohibit active discharge include Type I faults and Type II faults. Type I faults are motor controller malfunctions caused by hardware or software failures of the motor controller itself in the first or second motor subsystem. Type II faults are motor malfunctions caused by abnormalities in the motor itself in the first or second motor subsystem. Type I faults will cause the motor controller to malfunction and be unable to perform discharge logic control. Type II faults will cause the motor to cease operation. For Type I faults, the multi-motor system controller can quickly identify them by real-time monitoring of the motor controller's communication status, hardware status feedback signals, and software operation logs. For Type II faults, the controller can compare real-time parameters such as the motor's three-phase current, speed, and temperature with preset thresholds, and combine this with the validity of signals from the motor position sensors to determine if there are any abnormalities in the motor itself, such as three-phase short circuits, three-phase open circuits, or motor winding temperatures exceeding the corresponding safe temperature thresholds. When both the first motor subsystem and the second motor subsystem are in any of the above-mentioned fault types, the vehicle controller will determine that the subsystem is prohibited from performing active discharge operation, and then trigger the corresponding discharge process according to the combination of the fault states of the two subsystems.

[0065] In some embodiments, the second type of fault includes at least one of the following: three-phase short circuit, three-phase open circuit, and motor winding temperature exceeding a safe temperature threshold. The three-phase short circuit fault can be determined by real-time acquisition of the motor's three-phase current signals, comparing the amplitude differences of the three-phase currents, and checking for any abnormal peaks. The motor winding temperature exceeding the safe temperature threshold fault relies on real-time data from a temperature sensor installed on the motor itself. When the temperature value is higher than the preset safe temperature threshold for multiple consecutive sampling periods, the system confirms the fault. These fault identification results are fed back to the multi-motor system controller in real time, providing a basis for whether to prohibit active discharge operations.

[0066] Figure 5 A flowchart illustrating the active discharge process of a single motor, provided for at least one embodiment of this disclosure. Figure 2 , Figure 3 or Figure 4 Based on this, in order to ensure the active discharge effect, such as Figure 5 As shown, the single-motor active discharge process in step S30 further includes the following sub-steps S301-S305.

[0067] Sub-step S301: Determine which motor subsystem is fault-free in the first motor subsystem and the second motor subsystem.

[0068] Sub-step S302: Extend the active discharge timeout fault threshold (also known as safe discharge time) of the fault-free motor subsystem from the initial first threshold to a second threshold, wherein the second threshold is greater than the first threshold.

[0069] Sub-step S303: Send an active discharge command to the fault-free motor subsystem so that it discharges independently.

[0070] Sub-step S304: During the discharge process, monitor the bus voltage of the multi-motor system.

[0071] Sub-step S305: If the bus voltage drops below the safe voltage threshold within the discharge time corresponding to the second threshold, the multi-motor system discharge is determined to be complete.

[0072] If there is only one normal motor subsystem, the normal motor subsystem will perform active discharge and extend the safe discharge time beyond the normal limit to avoid interruption due to timeout.

[0073] Figure 6 A flowchart illustrating the active discharge process of a dual-motor system provided for at least one embodiment of this disclosure. Figure 2 , Figure 3 , Figure 4 or Figure 5 Based on this, in order to ensure the active discharge effect, such as Figure 6 As shown, the dual-motor cooperative active discharge process in step S40 includes the following sub-steps S401-S403.

[0074] Sub-step S401: Determine whether the clutch is in the disengaged state.

[0075] Sub-step S402: When the clutch is in the disengaged state, execute the first cooperative discharge strategy so that the first motor subsystem performs active discharge first in the multi-motor system, and wake up the second motor subsystem to perform active discharge synchronously when the discharge capacity of the first motor subsystem is insufficient.

[0076] Sub-step S403: When the clutch is in a non-disengaged state, execute the second cooperative discharge strategy so that multiple motor systems are actively discharged by the first motor subsystem and the second motor subsystem in a cooperative manner.

[0077] It should be noted that when the clutch is disengaged, the torque transmission path is broken, and mechanical torque cannot be transmitted between the first motor subsystem and the second motor subsystem. At this time, the first motor subsystem can independently undertake the main task of active discharge, while the second motor subsystem is in a relatively independent non-linkage state and will not generate additional torque coupling problems due to the discharge operation of the first motor subsystem. This provides mechanical support for prioritizing the use of the first motor subsystem for discharge, and also avoids the energy loss or control logic conflict that may occur when the two motor subsystems are not linked.

[0078] In the second motor subsystem, when the drive motor actively discharges, the torque generated by the motor may cause the whole vehicle to vibrate due to uncertain factors such as poor debugging, motor aging or abnormality. The above solution prioritizes the first motor subsystem (usually the ISG motor subsystem) directly connected to the engine to perform the active discharge strategy when the motor is in the disengaged state, which can effectively avoid the whole vehicle vibration.

[0079] When both motor subsystems are functioning normally, the above scheme further selects a discharge strategy based on the clutch status. When the clutch is engaged, the dual-system discharge is started synchronously to improve efficiency. When the clutch is disengaged, the first motor subsystem, which is the main motor, is given priority to perform discharge. If the timeout occurs, the backup motor is automatically activated to work together.

[0080] In some embodiments, Figure 6 Based on this, in order to ensure the high voltage safety of the system, the first cooperative discharge strategy includes the following sub-steps S402a-S402f.

[0081] Sub-step S402a: Extend the active discharge timeout fault threshold of the first motor subsystem from the first threshold to a third threshold that is different from the second threshold, wherein the third threshold is greater than the first threshold and less than the second threshold.

[0082] Sub-step S402b: Send an active discharge command to the first motor subsystem so that the first motor subsystem discharges independently.

[0083] Sub-step S402c: During the discharge process, monitor the bus voltage of the multi-motor system.

[0084] Sub-step S402d: Determine whether the bus voltage drops below the safe voltage threshold within the discharge time corresponding to the third threshold.

[0085] Sub-step S402e: If yes, determine that active discharge is complete.

[0086] Sub-step S402f: If not, determine that the discharge capacity of the first motor subsystem is insufficient, wake up the second motor subsystem, and send an active discharge command to the second motor subsystem so that the first motor subsystem and the second motor subsystem can discharge actively in sync.

[0087] The second threshold is the timeout fault threshold when the second motor subsystem performs active discharge alone. Its value is determined based on the rated discharge power of the second motor subsystem, the equivalent capacity of the bus capacitor, and the system's heat dissipation capacity. When both motor subsystems actively discharge synchronously, the vehicle controller needs to collect the discharge signals, temperature, and bus voltage change rate of both in real time, and dynamically adjust the discharge power distribution ratio of each subsystem to ensure that the bus voltage decreases smoothly without exceeding the preset rate of decrease limit. During synchronous discharge, if any motor subsystem is detected to have abnormal discharge power, temperature exceeding the allowable range, or communication interruption, the vehicle controller will immediately cut off the discharge circuit of that subsystem, while increasing the discharge power of the other subsystem to its allowable value and continuing to perform active discharge operation until the bus voltage drops below the safe voltage threshold or reaches the upper limit of the discharge time corresponding to the second threshold. If the voltage does not drop to the safe voltage after reaching the upper limit of the second threshold, an early warning mechanism is triggered to ensure the high voltage safety of the system.

[0088] The above scheme takes into account the active discharge condition of multi-motor systems. When one motor fails, the active discharge timeout fault threshold is adjusted to avoid discharge interruption and ensure high voltage safety.

[0089] In the above scheme, the first threshold parameter Ti1 can be set based on the provisions of the national standard GB / T18488. The condition for successful rapid discharge is that the bus capacitor voltage must drop to 60V or below within a discharge time range of ≤3 seconds. This standard is defined for a single motor subsystem.

[0090] In the above scheme, if a motor subsystem A has a fault and cannot discharge quickly on its own, motor subsystem B will perform rapid discharge simultaneously. In this case, the second threshold Ti2 corresponding to the discharge time is longer than the first threshold Ti1. For high voltage safety, the second threshold Ti2 is no longer subject to the 3s constraint.

[0091] In the above scheme, under the condition of clutch disengagement, the ISG motor subsystem is preferentially selected for rapid discharge. This selection is not a necessary operation under fault conditions. Therefore, the third threshold Ti3 satisfies Ti2 > Ti3 > Ti1.

[0092] In some embodiments, Figure 6 Based on this, in order to ensure the high voltage safety of the system, the second cooperative discharge strategy further includes the following sub-step S403a-sub-step S403.

[0093] Sub-step S403a: Send an active discharge command to the first motor subsystem and the second motor subsystem so that the first motor subsystem and the second motor subsystem start up synchronously and discharge together.

[0094] Sub-step S403b: During the discharge process, monitor the bus voltage of the multi-motor system.

[0095] Sub-step S403c: Determine whether the bus voltage drops below the safe voltage threshold within the discharge time corresponding to the first threshold.

[0096] Sub-step S403d: If yes, determine that the discharge is complete.

[0097] Sub-step S403e: If not, trigger a discharge timeout fault alarm.

[0098] The first threshold Ti1 must comply with the national standard GB / T18488, meaning that a successful rapid discharge is determined when the bus capacitor voltage drops to 60V or below within ≤3 seconds. If any motor subsystem is detected as faulty and unable to discharge normally during the coordinated discharge process, the system automatically switches to a single-motor subsystem independent discharge mode, and the discharge time threshold is adjusted to the second threshold Ti2, which is not subject to the 3-second constraint and is greater than Ti1. Furthermore, when the ISG motor subsystem is prioritized for discharge in the clutch disengaged state, the corresponding discharge time threshold is the third threshold Ti3, satisfying the relationship Ti2 > Ti3 > Ti1. Simultaneously, the safety voltage threshold can be set to 60V to ensure the high-voltage system is in a safe state after discharge. When switching to different threshold modes, the vehicle controller must synchronously update the time parameters in the monitoring logic to adapt to the corresponding discharge scenarios and ensure the high-voltage safety of the multi-motor system under various operating conditions.

[0099] Figure 7 An example flowchart of a discharge control method for a multi-motor system provided in at least one embodiment of this disclosure. Figure 7 As shown, the method includes the following steps: 1) The discharge requirement is triggered by the vehicle controller; 2) The vehicle controller determines whether there is a fault preventing active discharge in the ISG motor subsystem and MT motor subsystem. If both exist, proceed to step 3); otherwise, proceed to step 4). 3) Perform passive discharge; 4) The vehicle controller determines whether one of the motor subsystems has a fault that prevents active discharge. If so, proceed to step 5); otherwise, proceed to step 6. 5) Active discharge is performed by the motor subsystem without faults. At this time, the active discharge timeout fault threshold for 60V is increased and expanded from the first threshold Ti1 to the second threshold Ti2. Ti1 is a value less than 3s, and Ti2 is no longer subject to this restriction. 6) If neither of the two motor subsystems has a fault that prevents active discharge, determine whether the clutch is disengaged. If it is not disengaged, proceed to step 7); if it is disengaged, proceed to step 8). 7) Both motor subsystems execute the active discharge command; 8) The ISG motor subsystem executes the active discharge command with a timeout threshold of Ti3 (Ti2>Ti3>Ti1). It determines whether the timeout has occurred. If there is no timeout, the active discharge is completed. If the timeout has occurred, the MT motor subsystem is woken up to perform active discharge synchronously.

[0100] The vehicle controller continuously collects bus voltage data from the ISG motor subsystem and the MT motor subsystem. When the bus voltage of both systems drops below 60V and remains stable, the active discharge is considered to have been successfully completed. If the target voltage is not reached within the discharge time corresponding to the active discharge timeout fault threshold, the vehicle controller will activate a fault warning.

[0101] Figure 8 This is a structural block diagram of a discharge control device for a multi-motor system provided in at least one embodiment of the present disclosure. The device is applied to a multi-motor system having a first motor subsystem and a second motor subsystem. Figure 8 As shown, the discharge control device 10 of the multi-motor system includes a pre-processing unit 11, a first control unit 12, a second control unit 13, and a third control unit 14.

[0102] The preprocessing unit 11 is configured to determine whether the first motor subsystem and the second motor subsystem each have a fault that prevents active discharge.

[0103] The first control unit 12 is configured to execute a passive discharge process if both the first motor subsystem and the second motor subsystem have a fault that prohibits active discharge, so that both the first motor subsystem and the second motor subsystem are passively discharged.

[0104] The second control unit 13 is configured to execute a single-motor active discharge process if one of the first motor subsystem and the second motor subsystem is fault-free and the other has a fault that prohibits active discharge, so that the fault-free motor subsystem can actively discharge.

[0105] The third control unit 14 is configured to execute a dual-motor coordinated active discharge process if neither the first motor subsystem nor the second motor subsystem has a fault that prohibits active discharge, so that the first motor subsystem and the second motor subsystem discharge together.

[0106] The specific execution methods of each unit in the above system embodiments have been described in detail in the embodiments related to the method, and will not be elaborated here.

[0107] In some embodiments, Figure 8 Based on this, the preprocessing unit 11, the first control unit 12, the second control unit 13 and the third control unit 14 can be implemented by a controller or control module with corresponding programs.

[0108] This disclosure also provides a storage medium storing a program or instructions that, when executed by a processor, implement the steps of the method embodiments described above.

[0109] This disclosure also provides a program product, such as... Figure 9 As shown, the program product includes one or more processors 21 and memory 22. Figure 9 Take a processor 21 as an example.

[0110] The controller may also include an input device 23 and an output device 24.

[0111] The processor 21, memory 22, input device 23, and output device 24 can be connected via a bus or other means. Figure 9 Taking the example of a connection between China and Israel via a bus.

[0112] The processor 21 can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations of the above types of chips. The general-purpose processor can be a microprocessor or any conventional processor.

[0113] The memory 22, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the methods in the embodiments of this disclosure. The processor 21 executes various functional applications and data processing of the server by running the non-transitory software programs, instructions, and modules stored in the memory 22, thereby implementing the steps of the above-described method embodiments.

[0114] The memory 22 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created by the use of the processing device operated by the server. Furthermore, the memory 22 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 22 may optionally include memory remotely located relative to the processor 21, and these remote memories may be connected to a network connection device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0115] Input device 23 can receive input digital or character information, and generate key signal inputs related to driver settings and function control of the server's processing unit. Output device 24 may include display devices such as a display screen.

[0116] One or more modules are stored in memory 22, and when executed by one or more processors 21, they perform actions such as... Figure 1 The method shown.

[0117] Those skilled in the art will understand that all or part of the processes in the above method embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes described in the above method embodiments. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory (FM), hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium can also include combinations of the above types of memory.

[0118] Although embodiments of the present disclosure have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present disclosure, and such modifications and variations all fall within the scope defined by the appended claims.

[0119] Although embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A discharge control method of a multi-motor system applied to a multi-motor system having a first motor subsystem and a second motor subsystem, characterized by, The method comprises: determining whether each of the first motor subsystem and the second motor subsystem has a fault that prohibits active discharge; if both the first motor subsystem and the second motor subsystem have the fault that prohibits active discharge, performing a passive discharge process to passively discharge the first motor subsystem and the second motor subsystem; if one of the first motor subsystem and the second motor subsystem is fault-free and the other has the fault that prohibits active discharge, performing a single-motor active discharge process to actively discharge the fault-free motor subsystem; if neither the first motor subsystem nor the second motor subsystem has the fault that prohibits active discharge, performing a dual-motor cooperative active discharge process to cooperatively discharge the first motor subsystem and the second motor subsystem. The method further comprises:

2. The method of claim 1, wherein, determining whether the multi-motor system has a discharge requirement; and when the multi-motor system has the discharge requirement, generating a control instruction for determining whether each of the first motor subsystem and the second motor subsystem has the fault that prohibits active discharge to start discharge control of the multi-motor system. The method further comprises:

3. The method according to claim 1 or 2, characterized in that, when determining whether the multi-motor system has the discharge requirement, detecting health states of the first motor subsystem and the second motor subsystem; and acquiring health state parameters of the first motor subsystem and the second motor subsystem in the detection result to determine whether each of the first motor subsystem and the second motor subsystem has the fault that prohibits active discharge based on the health state parameters. The fault that prohibits active discharge comprises: a first type of fault, which is a motor controller runaway fault caused by hardware failure or software failure of a motor controller of the first motor subsystem or the second motor subsystem; and 4. The method according to claim 1 or 2, characterized in that, a second type of fault, which is a motor runaway fault caused by motor body abnormality of the first motor subsystem or the second motor subsystem. The single-motor active discharge process comprises: determining the fault-free motor subsystem from among the first motor subsystem and the second motor subsystem; 5. The method according to claim 1 or 2, characterized in that, extending an active discharge timeout fault threshold of the fault-free motor subsystem from an initial first threshold to a second threshold, wherein the second threshold is greater than the first threshold; sending an active discharge instruction to the fault-free motor subsystem to discharge it alone; monitoring a bus voltage of the multi-motor system during the discharging; and if the bus voltage drops below a safe voltage threshold within a discharging time corresponding to the second threshold, determining that the multi-motor system is discharged. The multi-motor system further comprises an engine directly connected to the first motor subsystem and a clutch arranged between the first motor subsystem and the second motor subsystem, and the dual-motor cooperative active discharge process comprises: determining whether the clutch is in a disengaged state; 6. The method of claim 1 or 2, wherein, ​ ​ The first cooperative discharging strategy is executed when the clutch is in the disengaged state, so that the multi-motor system preferentially performs active discharging by the first motor subsystem, and the second motor subsystem is woken up to synchronously perform active discharging when the discharging capacity of the first motor subsystem is insufficient. The second cooperative discharging strategy is executed when the clutch is in the non-disengaged state, so that the multi-motor system cooperatively performs active discharging by the first motor subsystem and the second motor subsystem.

7. The method of claim 6, wherein, The first cooperative discharging strategy comprises: The active discharging timeout failure threshold of the first motor subsystem is extended from a first threshold to a third threshold different from a second threshold, wherein the third threshold is greater than the first threshold and less than the second threshold; An active discharging instruction is sent to the first motor subsystem, so that the first motor subsystem discharges alone; During discharging, the bus voltage of the multi-motor system is monitored; It is judged whether the bus voltage is below a safe voltage threshold within a discharging time corresponding to the third threshold; If yes, it is determined that active discharging is completed; and If no, it is determined that the discharging capacity of the first motor subsystem is insufficient, the second motor subsystem is woken up, and an active discharging instruction is sent to the second motor subsystem, so that the first motor subsystem and the second motor subsystem synchronously perform active discharging.

8. The method of claim 6, wherein, The second cooperative discharging strategy comprises: An active discharging instruction is sent to the first motor subsystem and the second motor subsystem, so that the first motor subsystem and the second motor subsystem are synchronously started and cooperatively discharged; During discharging, the bus voltage of the multi-motor system is monitored; It is judged whether the bus voltage is below a safe voltage threshold within a discharging time corresponding to the first threshold; If yes, it is determined that discharging is completed; and If no, a discharging timeout failure alarm is triggered.

9. A discharge control device of a multi-motor system applied to a multi-motor system having a first motor subsystem and a second motor subsystem, characterized by, It comprises: A preprocessing unit configured to judge whether the first motor subsystem and the second motor subsystem each have a failure that prohibits active discharging; A first control unit configured to, if the first motor subsystem and the second motor subsystem each have a failure that prohibits active discharging, execute a passive discharging process, so that the first motor subsystem and the second motor subsystem are passively discharged; A second control unit configured to, if one of the first motor subsystem and the second motor subsystem is failure-free and the other each has a failure that prohibits active discharging, execute a single-motor active discharging process, so that the failure-free motor subsystem is actively discharged; And A third control unit configured to, if the first motor subsystem and the second motor subsystem each do not have a failure that prohibits active discharging, execute a double-motor cooperative active discharging process, so that the first motor subsystem and the second motor subsystem cooperatively discharge.

10. A storage medium, characterized by The storage medium stores a program or instructions, wherein the program or instructions, when executed by the processor, implement the steps of the method of any one of claims 1 to 8.

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