A method and control system for stall control of a motor controller

Abstract

The present invention provides a method and a control system for controlling the stall of a motor controller. The control method includes: when the motor is currently in a stall condition, determining the switching frequency of the motor inverter at the current moment based on the change difference Δn between the average value n1 of the rotor position angles within the current multiple sampling periods and the average value n2 of the rotor position angles within the adjacent historical multiple sampling periods; obtaining the motor speed N corresponding to the rotor position angle at the current moment s , comparing the motor speed N s with the reference speed N ref to make a difference comparison, and determining the corresponding position loop parameters and speed loop parameters according to the magnitude of the speed difference ΔN; realizing the closed-loop control of the motor based on the position loop parameters and the speed loop parameters to change the response ability of the motor controller at the stall moment. The present invention optimizes the current loop and speed loop parameters of the motor control system at the stall moment to adjust the system responsiveness, so as to improve the motor stall performance and prevent overheating at the stall moment.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and more specifically, to a method and a control system for controlling motor controller stall. Background Art

[0002] With the popularization of new energy vehicles, users are increasingly concerned about the safety and reliability of new energy vehicles. As a core component of the three electrics (battery, motor, and electric control system), the inverter has a risk of thermal failure under certain specific working conditions. Among them, the motor stall condition is a typical case of thermal failure.

[0003] In the design of an electric vehicle drive system, there is a performance index of maximum climbing. When an electric vehicle conducts a maximum climbing performance test, the tires may lock up. At this time, the motor speed of the electric vehicle approaches zero, and the motor stalls. When the motor stalls, the three-phase insulated gate bipolar transistor (IGBT) in the motor controller no longer switches, causing a certain phase of the IGBT to heat up rapidly, thereby burning out the IGBT and causing damage to the motor controller.

[0004] When a pure electric vehicle is in a ramp acceleration or stall condition, the control strategy of the motor becomes particularly important. Generally, it is required that the motor outputs a peak torque, the motor speed is low, and the corresponding current amplitude also reaches the peak. At this time, the insulated gate bipolar transistor (referred to as IGBT) is at a high switching frequency, and the corresponding IGBT switching loss is also very large, which will cause the IGBT temperature to rise rapidly. Especially in the case of repeated climbing, long-term ramp acceleration or stall, it may even cause the IGBT to burn out, posing a hidden danger to driving safety and reducing safety. Currently, when the vehicle is in the above-mentioned working conditions, the control strategy of the motor is not to change the frequency. Therefore, the safety of the whole vehicle system cannot be guaranteed.

[0005] To solve the above problems, most of the existing technologies adopt the method of reducing the actual output torque to meet the stalling requirements. However, this strategy cannot guarantee the effect of reducing the maximum temperature under the same torque output, and the method of reducing torque cannot meet the stalling requirements. In addition, in the method of reducing the maximum temperature rise of the stalling, the existing technology currently usually adds sensors to the three-phase IGBT respectively, monitors the temperature of each of the three-phase IGBT in real time, and determines whether the motor is stalled based on the corresponding maximum temperature value in the three-phase IGBT. However, the temperature value measured by the sensor on the IGBT has a large deviation and delay, which can easily cause the motor to be stalled for a long time before the alarm is fed back, and it is impossible to take protective measures in time, resulting in damage to the motor controller. At the same time, due to the addition of additional temperature detection equipment, the cost increases, and the method of adding temperature sensors needs to be combined with the steps of online temperature calculation, which makes the calculation complicated and occupies chip resources. Summary of the invention

[0006] The present invention aims at the technical problems existing in the prior art and provides a motor controller stall control method and a control system.

[0007] According to a first aspect of the present invention, a motor controller stall control method is provided, comprising:

[0008] Feedback torque T calculated in real time based on the motor controller e And the torque loading slope K, judge the current working state of the motor;

[0009] When the current working state of the motor is a stalled condition, the switching frequency of the motor inverter at the current moment is determined based on the change difference Δn between the rotor position angle average value n1 in the current multiple sampling periods and the rotor position angle average value n2 in the adjacent historical multiple sampling periods;

[0010] Get the motor speed N corresponding to the rotor position angle at the current moment s , the motor speed N s The reference speed N corresponding to the switching frequency of the motor inverter at the current moment ref Perform difference comparison and determine the corresponding position loop parameters and speed loop parameters according to the speed difference ΔN;

[0011] Closed-loop control of the motor is achieved based on the position loop parameters and the speed loop parameters to improve the response time of the motor controller.

[0012] Based on the above technical solution, the present invention can also make the following improvements.

[0013] Optionally, the feedback torque T calculated in real time based on the motor controller e And the torque loading slope K, judge the current working state of the motor, including:

[0014] Obtain the feedback torque T calculated in real time by the motor controller e , and obtain the change coefficient K of the motor torque when the motor feedback torque is loaded to 0.9*T max , where T max is the peak torque of the motor;

[0015] When the change coefficient K of the motor torque is greater than the throttle pedal opening change rate P in the stall state r0 , and the motor feedback torque T e is greater than 0.9*T max , it is determined that the motor is in the stall state, which is an unstable state;

[0016] Among them, the feedback torque T e is the motor output torque estimated in real time by the motor controller. The change coefficient K of the motor torque when the motor feedback torque is loaded to 0.9*T max is determined according to the throttle pedal opening change rate P fed back by the vehicle controller r , and the throttle pedal opening change rate P in the motor stall state r0 is obtained through actual calibration by the vehicle.

[0017] Optionally, when the current working state of the motor is the stall condition, based on the rotor position change difference Δn between the average rotor position angle n1 within the current multiple sampling periods and the average rotor position angle n2 within the adjacent historical multiple sampling periods, determine the switching frequency of the motor inverter at the current moment, including:

[0018] When the current working state of the motor is the stall condition, obtain the average rotor position angle n1 of the current multiple sampling periods and the average rotor position angle n2 of the adjacent historical multiple sampling periods through the rotor position sensor;

[0019] Based on the average rotor position angle n1 and the average rotor position angle n2, calculate the rotor position change difference Δn = n1 - n2;

[0020] According to the region range where the rotor position change difference Δn falls, determine the switching frequency of the motor inverter at the current moment.

[0021] Optionally, the region range where the rotor position change difference Δn falls is divided by the magnitude of the rotor position change difference Δn. Among them, the torque response corresponding to different rotor position change differences Δn is obtained by bench testing the stall characteristics of the permanent magnet synchronous motor, and then different region ranges of the rotor position change difference Δn are determined.

[0022] Optionally, it further includes:

[0023] When the current working state of the motor is the normal working state, determine the switching frequency of the motor inverter at the current moment according to the rotational speed N of the motor during normal operation, where the switching frequency of the motor inverter corresponding to different rotational speed ranges is obtained through bench calibration.

[0024] Optionally, the position loop parameter and the speed loop parameter are determined according to the magnitude of the rotational speed difference ΔN, and the current loop parameters K cp and K ci satisfy:

[0025]

[0026] where L is the inductance parameter of the motor, R is the resistance of the motor winding, and the relevant parameters are obtained through bench calibration;

[0027] Tune the current loop parameters by setting the current loop stable regulation time t s The current loop stable regulation time t s is:

[0028]

[0029] Obtain the values of the speed loop parameters K sp and K si according to the switching frequency of the motor inverter at the current moment, so that the rotational speed of the motor tends to be stable within the preset duration t3.

[0030] Optionally, based on the position loop parameter and the speed loop parameter to implement closed-loop control of the motor, it further includes:

[0031] Real-time collect the temperature T of the IGBT in the motor controller, and compare the temperature T of the IGBT with the stall warning temperature T0;

[0032] Based on the comparison result between the temperature T of the IGBT and the stall warning temperature T0, determine again whether the motor is in a stalled state.

[0033] Optionally, based on the comparison result between the temperature T of the IGBT and the stall warning temperature T0, determine again whether the motor is in a stalled state, including:

[0034] When the temperature T of the IGBT is greater than the stall warning temperature T0, it is determined that the motor is in a stalled state, and then limit the torque output of the motor controller;

[0035] where the stall warning temperature T0 is obtained through motor bench testing, by testing the highest temperature T that the motor can withstand when it is in a fully stalled state max , and the stall warning temperature T0 = 90%T max .

[0036] According to a second aspect of the present invention, there is provided a locked-rotor control system for a motor controller, including:

[0037] A judgment module, configured to judge the current working state of the motor based on the feedback torque T e calculated in real time by the motor controller and the torque loading slope K;

[0038] A first determination module, configured to determine the switching frequency of the motor inverter at the current moment based on the change difference Δn between the average value n1 of the rotor position angles within the current multiple sampling periods and the average value n2 of the rotor position angles within the adjacent historical multiple sampling periods when the current working state of the motor is a locked-rotor condition;

[0039] A second determination module, configured to obtain the motor speed N corresponding to the rotor position angle at the current moment s and compare the difference between the motor speed N s and the reference speed N corresponding to the switching frequency of the motor inverter at the current moment ref to determine the corresponding position loop parameter and speed loop parameter according to the magnitude of the speed difference ΔN;

[0040] A control module, configured to implement closed-loop control of the motor based on the position loop parameter and the speed loop parameter to improve the response time of the motor controller.

[0041] According to a third aspect of the present invention, there is provided an electronic device, including a memory and a processor, and the processor is configured to implement the steps of the locked-rotor control method for a motor controller when executing a computer management program stored in the memory.

[0042] According to a fourth aspect of the present invention, there is provided a computer-readable storage medium, on which a computer management program is stored, and the computer management program is configured to implement the steps of the locked-rotor control method for a motor controller when executed by a processor.

[0043] For a locked-rotor control method and control system for a motor controller provided by the present invention, when the motor is currently in a locked-rotor condition, the switching frequency of the motor inverter at the current moment is determined according to the change difference of the rotor positions in adjacent multiple sampling periods, and then the difference between the motor speed N s corresponding to the rotor position angle at the current moment and the reference speed N ref corresponding to the switching frequency of the motor inverter at the current moment is compared, and the corresponding position loop parameter and speed loop parameter are determined according to the magnitude of the speed difference ΔN; closed-loop control of the motor is implemented based on the position loop parameter and the speed loop parameter to improve the response time of the motor controller. The present invention optimizes the current loop and speed loop parameters of the motor control system at the locked-rotor moment to adjust the control system responsiveness so as to improve the locked-rotor performance of the motor and prevent overheating at the locked-rotor moment. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 Flow chart of a method for controlling motor controller stall provided by an embodiment of the present invention;

[0045] Figure 2 Schematic diagram of motor torque response corresponding to different speed differences;

[0046] Figure 3 Schematic diagram of motor speed response with different speed loop and current loop parameters;

[0047] Figure 4 Schematic diagram of the flow of a method for controlling motor controller stall provided by another embodiment of the present invention;

[0048] Figure 5 Schematic diagram of the structure of a system for FOC control of a motor controller;

[0049] Figure 6 Schematic diagram of the structure of a motor controller stall control system provided by the present invention;

[0050] Figure 7 Schematic diagram of the hardware structure of a possible electronic device provided by the present invention;

[0051] Figure 8 Schematic diagram of the hardware structure of a possible computer-readable storage medium provided by the present invention. Detailed implementation manners

[0052] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. In addition, the technical features in each embodiment or a single embodiment provided by the present invention can be combined with each other arbitrarily to form a feasible technical solution. This combination is not restricted by the order of steps and / or the mode of structural composition, but must be based on what can be achieved by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0053] In view of the problems in the background art, the present invention proposes a method and a control system for controlling motor controller stall in a new energy vehicle. This method can optimize the current loop and speed loop parameters of the motor control system at the stall moment to adjust the responsiveness of the control system, so as to improve the motor stall performance and prevent overheating at the stall moment.

[0054] Figure 1 Flow chart of a stall control method for a motor controller provided by the present invention, as Figure 1 shown, the method mainly includes the following steps:

[0055] S1, based on the feedback torque T e calculated in real time by the motor controller and the torque loading slope K, determine the current working state of the motor.

[0056] As an embodiment, the determining the current working state of the motor based on the feedback torque T e calculated in real time by the motor controller and the torque loading slope K includes:

[0057] Obtain the feedback torque T e calculated in real time by the motor controller, and obtain the change coefficient K of the motor torque when the motor feedback torque is loaded to 0.9*T max , where T max is the peak torque of the motor;

[0058] When the change coefficient K of the motor torque is greater than the throttle pedal opening change rate P r0 in the stall state, and the motor feedback torque T e is greater than 0.9*T max , it is determined that the motor is in the stall state.

[0059] It can be understood that before controlling the stall of the motor controller, first determine the current working state of the motor. If the motor is currently working in a stable state, there is no need to perform overcurrent control. When the motor is currently working in the stall state, control is required.

[0060] Among them, the motor controller calculates the feedback torque T e in real time and the real-time loading slope of the torque. When the feedback torque T e is loaded to 90% of the torque peak T max , obtain the torque loading slope K at this time (hereinafter referred to as the change coefficient of the motor torque). When the change coefficient K of the motor torque is greater than the throttle pedal opening change rate P r0 in the stall state, and the motor feedback torque T e is greater than 0.9*T max , it is determined that the motor is in the stall state.

[0061] Among them, the feedback torque T e is the motor output torque estimated in real time by the motor controller. The change coefficient K of the motor torque when the motor feedback torque is loaded to 0.9*T max is determined according to the throttle pedal opening change rate P r fed back by the vehicle control unit (VCU). The throttle pedal opening change rate P r0Obtained through actual calibration of the whole vehicle.

[0062] S2. When the current working state of the motor is the locked-rotor condition, based on the change difference Δn between the average value n1 of the rotor position angles within the current multiple sampling periods and the average value n2 of the rotor position angles within the adjacent historical multiple sampling periods, determine the switching frequency of the motor inverter at the current moment.

[0063] As an embodiment, when the current working state of the motor is the locked-rotor condition, based on the change difference Δn in rotor position between the average value n1 of the rotor position angles within the current multiple sampling periods and the average value n2 of the rotor position angles within the adjacent historical multiple sampling periods, determine the switching frequency of the motor inverter at the current moment, including: when the current working state of the motor is the locked-rotor condition, obtain the average value n1 of the rotor position angles within the current multiple sampling periods and obtain the average value n2 of the rotor position angles within the adjacent historical multiple sampling periods through the rotor position sensor; based on the average value n1 of the rotor position angles and the average value n2 of the rotor position angles, calculate the change difference in rotor position Δn = n1 - n2; according to the region range into which the change difference in rotor position Δn falls, determine the switching frequency of the motor inverter at the current moment.

[0064] It can be understood that when it is determined that the current working state of the motor is the locked-rotor condition, the average value n1 of the rotor position angles within 10 sampling periods and the average value n2 of the rotor position angles within the next 10 sampling periods are obtained through the rotor position sensor, and the change difference in rotor position Δn is obtained based on the average value n1 of the position angles and the average value n2 of the position angles, and the region where the change difference in rotor position Δn is located is judged. Based on the region into which the change difference in rotor position Δn falls, determine the switching frequency of the inverter at the current moment. If the motor is in a non-locked-rotor state, the switching frequency T of the inverter is determined according to the current speed N of the motor pwm0 。

[0065] Among them, the average value n1 of the rotor position angles is the average value of the rotor position angles within 10 sampling periods including the current moment, and is obtained through formula (1):

[0066]

[0067] The average value n2 of the rotor position angles is the average value of the rotor position angles within the previous 10 sampling periods, and is obtained through formula (2):

[0068]

[0069] The region where the change difference in rotor position Δn is located is divided according to the magnitude of the change difference in rotor position Δn, as shown in Table 1.

[0070] Table 1 Region division corresponding to the rotational speed difference range

[0071] Speed difference range (r / min) 20 40 60 80 100 Speed region Ⅰ Ⅱ Ⅲ Ⅳ Ⅴ

[0072] Among them, the torque response corresponding to different speed differences Δn is obtained by bench testing the locked-rotor characteristics of the permanent magnet synchronous motor, Figure 2 A schematic diagram showing the torque response corresponding to different speed differences Δn is shown, and then the division method corresponding to different speed differences is determined. The non-locked-rotor state of the motor is the normal working state of the motor. At this time, the inverter switching frequency T pwm0 is determined according to the speed N of the motor during normal operation, and the switching frequency within different speed ranges is obtained through bench calibration in the prior art.

[0073] According to Table 1, the regional range corresponding to the change difference Δn of the rotor position angle in the locked-rotor state of the motor is determined, and the switching frequency T in the locked-rotor state is determined according to the corresponding regional range pwm1 , the switching frequency T pwm1 is obtained through bench calibration. Table 2 shows the switching frequencies corresponding to different regional ranges in the locked-rotor state of the motor.

[0074] Table 2 Switching frequencies corresponding to different regions in the locked-rotor state

[0075]

[0076] S3. Obtain the motor speed N corresponding to the rotor position angle at the current moment s , and compare the motor speed N s with the reference speed N corresponding to the switching frequency of the motor inverter at the current moment ref to make a difference comparison, and determine the corresponding position loop parameters and speed loop parameters according to the magnitude of the speed difference ΔN.

[0077] It can be understood that the switching frequency of the motor at the current moment is obtained in the above step S2. Among them, the switching frequency has a corresponding relationship with the reference speed N ref .

[0078] In this step, obtain the motor speed N corresponding to the rotor position angle at the current moment s , compare the motor speed N s with the reference speed N corresponding to the switching frequency of the motor inverter at the current moment ref to make a difference comparison, and determine the position loop parameters and speed loop parameters at the current moment based on the comparison result.

[0079] Specifically, the motor speed N corresponding to the rotor position angle s is the real-time speed of the motor, and the reference speed N ref is the corresponding motor speed determined according to the current throttle opening of the whole vehicle and the magnitude of the three-phase current in the non-locked-rotor state, and is related to the switching frequency of the motor at the current moment. The speed difference is the current motor speed N sWith the corresponding reference speed N ref The speed difference ΔN = N s - N ref , the current loop parameters K cp 、K ci and the speed loop parameters K sp 、K si are determined according to the speed difference ΔN. Specifically, the current loop parameters are tuned for PI parameters according to different speed difference ranges ΔN. To avoid overcurrent caused by overshoot, the current loop parameters K cp and K ci shall satisfy:

[0080]

[0081] where L is the inductance parameter of the motor and R is the resistance of the motor winding. The relevant parameters are obtained through bench calibration.

[0082] By setting the current loop stable regulation time t s , the current loop parameters are tuned. The current loop stable regulation time t s is:

[0083]

[0084] The speed loop parameters K sp 、K si are determined according to the speed difference ΔN. During the determination process, the speed loop parameters are adjusted to the speed loop parameters K Figure 3 corresponding to t3 as shown in sp 、K si . The speed of the motor tends to be stable at the preset duration t3. The speed loop parameters shown by t3 have good stability and a long speed response time. Finally, the corresponding current loop and speed loop PI parameters at different switching frequencies are obtained.

[0085] It should be noted that when it is determined in step S1 that the current working state of the motor is a stable state, the switching frequency of the motor at the current moment is determined based on the current speed of the motor, and according to the speed difference between the current speed N s of the motor at the current moment and the reference speed N ref corresponding to the switching frequency of the motor at the current moment, the corresponding current loop parameters and speed loop parameters are obtained.

[0086] Among them, the position loop and speed loop parameters corresponding to different speed differences can be seen in Table 3.

[0087] Table 3. Current loop and speed loop PI parameters corresponding to different speed differences

[0088]

[0089]

[0090] S4. Implement closed-loop control of the motor based on the position loop parameters and speed loop parameters to improve the response time of the motor controller.

[0091] Among them, after obtaining the position loop parameters and speed loop parameters of the motor at the current moment, closed-loop control of the motor is implemented.

[0092] As an embodiment, implementing closed-loop control of the motor based on the position loop parameters and speed loop parameters further includes: real-time collecting the temperature T of the IGBT in the motor controller, comparing the temperature T of the IGBT with the stall warning temperature T0; based on the comparison result of the temperature T of the IGBT and the stall warning temperature T0, determining again whether the motor is in a stalled state.

[0093] Among them, based on the comparison result of the temperature T of the IGBT and the stall warning temperature T0, determining again whether the motor is in a stalled state includes: when the temperature T of the IGBT is greater than the stall warning temperature T0, it is determined that the motor is in a stalled state, and then the torque output of the motor controller is restricted; among them, the stall warning temperature T0 is obtained through motor bench testing, and by testing the highest temperature T that the motor can withstand when it is in a fully stalled state max , the stall warning temperature T0 = 90%T max .

[0094] It can be understood that during the process of implementing closed-loop control of the motor based on the position loop parameters and speed loop parameters, it is also necessary to detect whether the closed-loop control reduces the temperature of the motor controller. Therefore, during the entire process of closed-loop control, the temperature T of the IGBT in the motor controller is collected in real time, and the temperature T of the IGBT is compared with the stall warning temperature T0. If T > T0, then the motor is still in a stalled state, indicating that the current closed-loop control has no effect, and other measures need to be taken to ensure that the temperature of the motor does not become too high.

[0095] Specifically, the stall warning temperature T0 is obtained through motor bench testing, and by testing the highest temperature T that the motor can withstand when it is in a fully stalled state (speed is 0 and 90% of the peak torque is loaded) max , the stall warning temperature T0 = 90%T max . When the IGBT temperature T collected by the motor temperature sensor at the current moment is greater than 90%T max , the motor is in an over-temperature state. To prevent damage to the IGBT, the power of the motor is restricted at this time.

[0096] See Figure 4 , which is the overall flowchart of a stall control method for a motor controller provided by the present invention. The main steps of this stall control method are as follows:

[0097] (1) The motor controller determines whether the motor stalling condition is met by calculating the magnitude of the feedback torque T and the torque loading slope K in real time. e and the torque loading slope K to determine whether the motor stalling condition is satisfied.

[0098] (2) If the motor is in a stalled condition, the average rotor position angle n1 of the current 10 sampling periods and the average rotor position angle n2 of the previous 10 sampling periods are obtained through the rotor position sensor, and the change difference Δn = n1 - n2 of the rotor position angle is obtained based on the average position angle n1 and the average position angle n2, and the region where the rotor position change difference Δn is located is determined. If the motor is in a non-stalled state, the inverter switching frequency T at the current moment is determined according to the current speed N. pwm0 .

[0099] (3) The inverter switching frequency T at the current moment is determined according to the region corresponding to the rotor position change difference Δn in the current stalled state. pwm1 .

[0100] (4) The motor speed N corresponding to the rotor position angle at the current moment is obtained through the rotor position sensor. s , and the current motor speed N s is compared with the reference speed N corresponding to the inverter switching frequency at the current moment. ref The current loop parameters K cp , K ci and the speed loop parameters K sp , K si are determined according to the magnitude of the speed difference. If the motor is in a non-stalled state, the current loop parameters are K cp0 , K ci0 , and the speed loop K sp0 , K si0 .

[0101] (5) Based on the position loop parameters and the speed loop parameters, closed-loop control of the motor is achieved. The IGBT temperature T is collected in real time through the temperature sensor and compared with the stalling warning temperature T0. According to the comparison result of the current IGBT temperature T and the stalling warning temperature T0, the stalling state of the motor is judged again. If the motor is still in a stalled state, the output torque polarity control of the motor is required.

[0102] Among them, referring to Figure 5 , it is a system for FOC control of the motor controller. The permanent magnet synchronous motor control system mainly includes a current loop PI regulator, a speed loop PI regulator, a Park inverse transformation module, an SVPWM module, an Inverter inverter module, a Clark transformation module, a Park transformation module, a permanent magnet synchronous motor, etc. The MCU is based on the permanent magnet synchronous motor speed reference signal n refAfter performing a difference operation with the actual rotational speed n collected by the motor rotor position sensor, it passes through the speed loop PI and then through the MTPA operation to obtain the quadrature and direct-axis currents iq reh and id reh The current loop PI regulator and the speed loop PI regulator then regulate the quadrature and direct-axis currents i q * and i d * and convert them into the quadrature and direct-axis voltages u q and u d Then, through the Park inverse transformation module, they are converted into u β and u α Finally, through the SVPWM module, they are converted into the switching signals for controlling the Inverter inverter module to control the Inverter to output alternating three-phase currents, thereby controlling the permanent magnet synchronous motor. The Clark transformation module converts the three-phase currents into i α and i β and through the Park transformation module, they are converted into i d and i q Thereby realizing the closed-loop control of the current.

[0103] When the motor is in a stalled condition, the present invention determines the switching frequency of the motor inverter at the current moment according to the change difference of the rotor position in adjacent multiple sampling periods, and then compares the motor speed N s corresponding to the rotor position angle at the current moment with the reference speed N ref corresponding to the switching frequency of the motor inverter at the current moment. According to the magnitude of the speed difference ΔN, the corresponding position loop parameters and speed loop parameters are determined; based on the position loop parameters and speed loop parameters, the closed-loop control of the motor is realized to improve the response time of the motor controller. The present invention optimizes the current loop and speed loop parameters of the motor control system at the stalled moment to adjust the control system responsiveness to achieve improving the motor stalling performance and preventing overheating at the stalled moment.

[0104] See Figure 6 The present invention provides a motor controller stalling control system. The stalling control system includes a judgment module 601, a first determination module 602, a second determination module 603, and a control module 604, where:

[0105] The judgment module 601 is used to judge the current working state of the motor based on the feedback torque T e calculated in real time by the motor controller and the torque loading slope K;

[0106] The first determination module 602 is configured to determine the switching frequency of the motor inverter at the current moment based on the change difference Δn between the average rotor position angle n1 within the current multiple sampling periods and the average rotor position angle n2 within the adjacent historical multiple sampling periods when the current operating state of the motor is a stalled condition.

[0107] The second determination module 603 is configured to obtain the motor speed N corresponding to the rotor position angle at the current moment. s and compare the difference between the motor speed N s and the reference speed N corresponding to the switching frequency of the motor inverter at the current moment. ref Based on the speed difference ΔN, determine the corresponding position loop parameter and speed loop parameter.

[0108] The control module 604 is configured to implement closed-loop control of the motor based on the position loop parameter and speed loop parameter to improve the response time of the motor controller.

[0109] It can be understood that a motor controller stall control system provided by the present invention corresponds to the motor controller stall control method provided in the foregoing embodiments. The related technical features of the motor controller stall control system can refer to the related technical features of the motor controller stall control method, which will not be elaborated here.

[0110] Please refer to Figure 7 , Figure 7 which is a schematic diagram of an embodiment of an electronic device provided by an embodiment of the present invention. As Figure 7 shown, an embodiment of the present invention provides an electronic device 700, including a memory 710, a processor 720, and a computer program 711 stored on the memory 710 and executable on the processor 720. When the processor 720 executes the computer program 711, the following steps are implemented: Based on the feedback torque T e calculated by the motor controller in real time and the torque loading slope K, determine the current operating state of the motor; when the current operating state of the motor is a stalled condition, based on the change difference Δn between the average rotor position angle n1 within the current multiple sampling periods and the average rotor position angle n2 within the adjacent historical multiple sampling periods, determine the switching frequency of the motor inverter at the current moment; obtain the motor speed N corresponding to the rotor position angle at the current moment. s and compare the difference between the motor speed N s and the reference speed N corresponding to the switching frequency of the motor inverter at the current moment. ref Based on the speed difference ΔN, determine the corresponding position loop parameter and speed loop parameter; implement closed-loop control of the motor based on the position loop parameter and speed loop parameter to improve the response time of the motor controller.

[0111] Please refer to Figure 8 ,Figure 8 Schematic diagram of an embodiment of a computer-readable storage medium provided by the present invention. As Figure 8 shown, this embodiment provides a computer-readable storage medium 800, on which a computer program 811 is stored. When the computer program 811 is executed by a processor, the following steps are implemented: Based on the feedback torque T e and the torque loading slope K calculated in real time by the motor controller, determine the current working state of the motor; when the current working state of the motor is a locked-rotor condition, based on the change difference Δn between the average value n1 of the rotor position angles within the current multiple sampling periods and the average value n2 of the rotor position angles within the adjacent historical multiple sampling periods, determine the switching frequency of the motor inverter at the current moment; obtain the motor speed N s corresponding to the rotor position angle at the current moment, and s compare the difference between the motor speed N ref at the current moment and the reference speed N corresponding to the switching frequency of the motor inverter at the current moment. Determine the corresponding position loop parameters and speed loop parameters according to the magnitude of the speed difference ΔN; implement closed-loop control of the motor based on the position loop parameters and speed loop parameters to improve the response time of the motor controller.

[0112] A method and control system for locked-rotor control of a motor controller provided by an embodiment of the present invention determine the region where the difference between the average values of the motor rotor position angles at adjacent moments is located in the locked-rotor state, and adjust the switching frequency according to the region. At the same time, according to the torque response characteristics of a permanent magnet synchronous motor in the locked-rotor state, by adjusting the PI parameters of the speed loop and the PI parameters of the current loop according to the magnitude of the difference between the motor speed and the reference speed at the current moment, the speed response time is increased on the premise of satisfying the motor current response, thereby achieving the effect of increasing the maximum locked-rotor time and preventing thermal failure of the inverter. Compared with the prior art method of reducing the maximum temperature rise by reducing the actual output torque, the present invention can achieve a reduction in the maximum temperature without reducing the output torque, thereby protecting the inverter. In addition, compared with the prior art method that requires additional temperature detection devices (such as temperature sensors) to assist in implementation, this method can greatly reduce costs, while the method of adding temperature sensors requires combining steps of online temperature calculation, resulting in complex calculations and occupying chip resources.

[0113] It should be noted that in the above embodiments, the descriptions of the various embodiments have their own emphases. For parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0114] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0115] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in Figure 1 one or more of the processes Figure 1 or a plurality of processes and / or blocks

[0116] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in Figure 1 one or more of the processes Figure 1 or a plurality of processes and / or blocks

[0117] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in Figure 1 one or more of the processes Figure 1 or a plurality of processes and / or blocks

[0118] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0119] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A method for controlling the stall of a motor controller, characterized in that, Including: Feedback torque T calculated in real time based on the motor controller e and torque loading slope K to determine the current operating state of the motor; When the current working state of the motor is the locked-rotor condition, determine the switching frequency of the motor inverter at the current moment based on the change difference Δn between the average value n1 of the rotor position angles in the current multiple sampling periods and the average value n2 of the rotor position angles in the adjacent historical multiple sampling periods; Obtain the motor speed N corresponding to the rotor position angle at the current moment s , and compare the motor speed N s with the reference speed N corresponding to the switching frequency of the motor inverter at the current moment ref to perform a difference comparison, and determine the corresponding position loop parameters and speed loop parameters according to the magnitude of the speed difference ΔN; Implement closed-loop control of the motor based on the position loop parameters and speed loop parameters to improve the response time of the motor controller; The step of, when the current working state of the motor is the locked-rotor condition, determining the switching frequency of the motor inverter at the current moment based on the change difference Δn in rotor position between the average value n1 of the rotor position angles in the current multiple sampling periods and the average value n2 of the rotor position angles in the adjacent historical multiple sampling periods, includes: When the current working state of the motor is the locked-rotor condition, obtain the average value n1 of the rotor position angles in the current multiple sampling periods and the average value n2 of the rotor position angles in the adjacent historical multiple sampling periods through a rotor position sensor; Based on the average value n1 of the rotor position angles and the average value n2 of the rotor position angles, calculate the change difference in rotor position Δn = n1 - n2; Determine the switching frequency of the motor inverter at the current moment according to the region range in which the change difference Δn in rotor position falls.

2. The motor controller stall control method according to claim 1, wherein The feedback torque T calculated in real time based on the motor controller e and the torque loading slope K are used to determine the current working state of the motor, including: Obtain the feedback torque T calculated in real time by the motor controller e , and obtain the change coefficient K of the motor torque when the motor feedback torque is loaded to 0.9*T max , where T max is the peak torque of the motor; When the change coefficient K of the motor torque is greater than the throttle pedal opening change rate P in the stall state r0 , and the motor feedback torque T e is greater than 0.9*T max , it is determined that the motor is in the stall state; Among them, the feedback torque T e is the motor output torque estimated in real time by the motor controller, and the change coefficient K of the motor torque when the motor feedback torque is loaded to 0.9*T max is determined according to the change rate P r of the accelerator pedal opening degree fed back by the vehicle controller. The change rate P r0 of the accelerator pedal opening degree in the motor stall state is obtained through actual calibration by the vehicle.

3. The motor controller stall control method according to claim 1, wherein The region range in which the change difference Δn in rotor position falls is obtained by dividing the magnitude of the change difference Δn in rotor position. Among them, the torque response corresponding to different change differences Δn in rotor position is obtained by bench testing the locked-rotor characteristics of the permanent magnet synchronous motor, and then different region ranges of the change difference Δn in rotor position are determined.

4. The motor controller stall control method according to claim 1, wherein Also including: When the current working state of the motor is the normal working state, determine the switching frequency of the motor inverter at the current moment according to the speed N of the motor during normal operation, where the switching frequency of the motor inverter corresponding to different speed ranges is obtained through bench calibration.

5. The motor controller stall control method according to claim 1, characterized in that The position loop parameters and speed loop parameters are determined according to the magnitude of the speed difference ΔN, and the current loop parameters K cp and K ci satisfy: Wherein, L is the inductance parameter of the motor, and R is the resistance of the motor winding, and relevant parameters are obtained through bench calibration; By setting the current loop stable regulation time t s Tune the parameters of the current loop, and the current loop stable regulation time t s is as follows: Take values for the speed loop parameters K sp and K si according to the switching frequency of the motor inverter at the current moment, so that the speed of the motor tends to be stable within the preset duration t3.

6. The motor controller stall control method according to any one of claims 1-5, characterized in that Implementing closed-loop control of the motor based on the position loop parameters and speed loop parameters further includes: Real-time collect the temperature T of the IGBT in the motor controller, and compare the temperature T of the IGBT with the locked-rotor warning temperature T0; Based on the comparison result between the temperature T of the IGBT and the locked-rotor warning temperature T0, determine again whether the motor is in the locked-rotor state.

7. The motor controller stall control method according to claim 6, wherein Based on the comparison result between the temperature T of the IGBT and the locked-rotor warning temperature T0, determining again whether the motor is in the locked-rotor state includes: When the temperature T of the IGBT is greater than the locked-rotor warning temperature T0, determine that the motor is in the locked-rotor state, and then limit the torque output of the motor controller; Among them, the locked-rotor warning temperature T0 is obtained through motor bench testing by testing the highest temperature T that the motor can withstand when it is in a completely locked-rotor state max , and the locked-rotor warning temperature T0 = 90%T max .

8. A motor controller locked-rotor control system, characterized in that, Including: A judgment module, configured to judge the current working state of the motor based on the feedback torque T calculated in real time by the motor controller e and the torque loading slope K A first determination module, configured to, when the current working state of the motor is the locked-rotor condition, determine the switching frequency of the motor inverter at the current moment based on the change difference Δn between the average value n1 of the rotor position angles in the current multiple sampling periods and the average value n2 of the rotor position angles in the adjacent historical multiple sampling periods; A second determination module, configured to obtain the motor speed N corresponding to the rotor position angle at the current moment s , and compare the motor speed N s with a reference speed N corresponding to the switching frequency of the motor inverter at the current moment ref to perform a difference comparison, and determine corresponding position loop parameters and speed loop parameters according to the magnitude of the speed difference ΔN; A control module, configured to implement closed-loop control of the motor based on the position loop parameters and speed loop parameters to improve the response time of the motor controller; When the current working state of the motor is a stall condition, determining the switching frequency of the motor inverter at the current moment based on the rotor position change difference Δn between the average rotor position angle n1 within the current multiple sampling periods and the average rotor position angle n2 within the adjacent historical multiple sampling periods includes: When the current working state of the motor is a stall condition, obtaining the average rotor position angle n1 of the current multiple sampling periods and obtaining the average rotor position angle n2 of the adjacent historical multiple sampling periods through a rotor position sensor; Based on the average rotor position angle n1 and the average rotor position angle n2, calculating the rotor position change difference Δn = n1 - n2; Determining the switching frequency of the motor inverter at the current moment according to the region range into which the rotor position change difference Δn falls.

9. A computer-readable storage medium, characterized in that, A computer management program is stored thereon, and when the computer management program is executed by a processor, the steps of the stall control method of the motor controller according to any one of claims 1-7 are implemented.

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