Motor temperature compensation method, device, equipment and storage medium

Abstract

The present application discloses a motor temperature compensation method, device, equipment and storage medium, and relates to the field of motor thermal management technology. The motor temperature compensation method includes: obtaining the electrical parameters of the motor, establishing a motor heating model of the motor under a stalled rotor condition based on the electrical parameters, wherein the motor heating model is used to calculate the actual temperature change of the motor caused by the heating of the winding copper loss under the stalled rotor condition; determining whether the motor needs temperature compensation according to the current torque state of the motor; if it is determined that the motor needs temperature compensation, obtaining the torque value of the motor under the stalled rotor condition, and determining the compensation temperature according to the torque value and the motor heating model; obtaining the sampling temperature of the temperature sensor in the motor, and determining the local maximum temperature after temperature compensation according to the sampling temperature and the compensation temperature. The present application can accurately collect the local maximum temperature of the motor under the stalled rotor condition.

Description

Technical Field

[0001] The present application relates to the technical field of motor thermal management, and in particular to a motor temperature compensation method, device, equipment and storage medium. Background Art

[0002] Permanent magnet synchronous motors, as a type of motor with high efficiency and high power density, have been widely used in many fields such as industrial production, electric vehicles, and precision instruments in recent years.

[0003] In actual operation, the phenomenon that the motor cannot start or stops rotating due to reasons such as excessive motor load, mechanical failure of the drag, bearing damage and bore sweeping is called motor stalling. When the permanent magnet synchronous motor is stalled, the magnetic circuit of the motor is in a highly saturated state, causing the inductance of the windings of different phases to change, which in turn affects the current distribution, resulting in possible differences in the three-phase current and local overheating of the motor. In this case, since the temperature sensors in the motor are randomly arranged, the positions of the arranged temperature sensors will be unreasonable, and the current local maximum temperature of the motor cannot be detected, and the thermal protection mechanism of the motor cannot be triggered according to the maximum temperature, which makes it easy for the motor to burn out.

[0004] Therefore, permanent magnet synchronous motors are prone to temperature acquisition distortion under stall conditions, and the inability to collect the local maximum temperature of the motor has become a problem that needs to be solved urgently.

[0005] The above contents are only used to assist in understanding the technical solution of the present application and do not constitute an admission that the above contents are prior art. Summary of the invention

[0006] The main purpose of the present application is to provide a motor temperature compensation method, device, equipment and storage medium, aiming to solve the technical problem that permanent magnet synchronous motors are prone to temperature acquisition distortion under stall conditions and cannot collect the local maximum temperature of the motor.

[0007] To achieve the above object, the present application proposes a motor temperature compensation method, the motor temperature compensation method comprising:

[0008] Acquire electrical parameters of the motor, and establish a motor heating model of the motor under a stalled rotor condition based on the electrical parameters, wherein the motor heating model is used to calculate an actual temperature change of the motor caused by heating of winding copper loss under the stalled rotor condition;

[0009] Determining whether the motor needs temperature compensation according to the current torque state of the motor;

[0010] If it is determined that the motor needs temperature compensation, obtaining the torque value of the motor under a stalled rotor condition, and determining a compensation temperature according to the torque value and the motor heating model;

[0011] A sampling temperature of a temperature sensor in the motor is obtained, and a local maximum temperature after temperature compensation is determined according to the sampling temperature and the compensation temperature.

[0012] In one embodiment, the step of establishing a motor heating model of the motor under a stalled rotor condition based on the electrical parameters comprises:

[0013] Determine the temperature rise model of the motor caused by the heating of the winding copper loss under the stall condition;

[0014] Determine a thermal model prototype corresponding to the electrical parameters, perform a motor locked-rotor condition test on the thermal model prototype, and obtain multiple groups of test data generated during the test, wherein multiple thermocouples are attached to the thermal model prototype to detect the actual temperature of different parts of the thermal model prototype, and the external cooling conditions during the test are the same as the external cooling conditions of the actual operating environment of the motor;

[0015] Fitting the copper loss heating coefficient and the heat dissipation coefficient according to the test data and the temperature rise model;

[0016] A motor heating model is established according to the copper loss heating coefficient, the heat dissipation coefficient and the temperature rise model.

[0017] In one embodiment, the step of performing a motor stall condition test on the thermal model prototype and acquiring multiple groups of test data generated during the test includes:

[0018] Applying a stall torque to the thermal model prototype at different electrical angles to obtain test data during the stall process at each electrical angle, wherein the test data includes a torque value, a test sampling temperature, a maximum actual temperature, and a torque request time;

[0019] Calculate the temperature difference between the test sampling temperature and the highest actual temperature at each electrical angle, and determine the target electrical angle with the largest temperature difference according to the temperature difference corresponding to each electrical angle;

[0020] A plurality of different stall torques are applied to the thermal model prototype at the target electrical angle to obtain a plurality of groups of test data in each stall process.

[0021] In one embodiment, the step of applying the stall torque to the thermal model prototype at different electrical angles and obtaining test data during the stall process at each electrical angle includes:

[0022] Obtaining a preset initial electrical angle, using the preset initial electrical angle as a simulated electrical angle, and applying a stall torque to the thermal model prototype based on the simulated electrical angle until the actual temperature of the motor collected by each thermocouple in the thermal model prototype reaches a preset maximum temperature of the thermal model prototype;

[0023] Obtaining a torque value of the stall torque, determining a test sampling temperature collected by a temperature sensor in the thermal model prototype, determining actual temperatures collected by each thermocouple in the thermal model prototype, and determining a highest actual temperature with the highest temperature from each actual temperature, obtaining a torque request time during the stall process, and using the torque value, the test sampling temperature, the highest actual temperature, and the torque request time as test data for the simulated electrical angle;

[0024] The simulated electrical angle is incremented based on a preset growth electrical angle, and the execution step is returned to: a stall torque is applied to the thermal model prototype based on the simulated electrical angle until the actual temperature of the motor collected by each thermocouple in the thermal model prototype reaches a preset maximum temperature of the thermal model prototype.

[0025] In one embodiment, the step of determining whether the motor needs to be temperature compensated according to the current torque state of the motor includes:

[0026] Performing torque detection on the motor to determine whether the current torque of the motor is a stall torque;

[0027] If the current torque is a stall torque, determining whether the speed of the motor is less than a preset stall speed;

[0028] If the rotation speed of the motor is less than the preset stall speed, it is determined that the torque state is a stall state, and it is determined that the motor needs to be temperature compensated.

[0029] In one embodiment, the step of determining the compensation temperature according to the torque value and the motor heating model comprises:

[0030] Obtaining the duration of the motor being in a stalled state;

[0031] Inputting the torque value into the motor heating model to obtain a first compensation temperature per unit time;

[0032] The first compensation temperature of each unit time within the duration is accumulated to obtain the compensation temperature at the current moment.

[0033] In one embodiment, after the step of accumulating the first compensation temperature of each unit time within the duration to obtain the compensation temperature at the current moment, the method further includes:

[0034] Acquire the current electrical angle of the motor and the target electrical angle corresponding to the motor heating model;

[0035] The correction factor of the compensation temperature is determined according to the current electrical angle and the target electrical angle, wherein the correction factor represents the current change ratio relative to the target electrical angle at the current electrical angle, and the calculation formula of the correction factor is expressed as: ,in, is the current electrical angle, is the target electrical angle;

[0036] The compensation temperature is corrected according to the correction factor to determine a corrected compensation temperature.

[0037] In addition, to achieve the above-mentioned purpose, the present application also proposes a motor temperature compensation device, the motor temperature compensation device comprising:

[0038] A model module, used to obtain electrical parameters of the motor, and to establish a motor heating model of the motor under a stalled rotor condition based on the electrical parameters, wherein the motor heating model is used to calculate an actual temperature change of the motor caused by heating of winding copper loss under the stalled rotor condition;

[0039] A judgment module, used for determining whether the motor needs temperature compensation according to the current torque state of the motor;

[0040] A calculation module, for obtaining a torque value of the motor under a stalled condition if it is determined that the motor needs temperature compensation, and determining a compensation temperature according to the torque value and a heating model of the motor;

[0041] The compensation module is used to obtain the sampled temperature of the temperature sensor in the motor, and determine the local maximum temperature after temperature compensation according to the sampled temperature and the compensation temperature.

[0042] In addition, to achieve the above-mentioned purpose, the present application also proposes a motor temperature compensation device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the motor temperature compensation method as described above.

[0043] In addition, to achieve the above objectives, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the motor temperature compensation method described above are implemented.

[0044] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the motor temperature compensation method as described above are implemented.

[0045] This application obtains the electrical parameters of the motor, and establishes a motor heating model under the stall condition based on the electrical parameters. This model calculates the actual temperature change of the winding due to copper loss, and determines whether the motor needs temperature compensation according to the current torque state of the motor. Only when it is confirmed that the motor is indeed in a stall and it is necessary to perform temperature compensation, the compensation mechanism is activated to avoid unnecessary resource consumption and misoperation. If it is determined that the motor needs temperature compensation, the torque value of the motor under the stall condition is obtained, and the compensation temperature is determined according to the torque value and the motor heating model. Once it is determined that compensation is required, the system will use the torque value and the previously established heating model to calculate the compensation temperature corresponding to the additional heating caused by the stall, obtain the sampling temperature of the temperature sensor in the motor, and determine the local maximum temperature after temperature compensation according to the sampling temperature and the compensation temperature. This local maximum temperature more accurately reflects the thermal state of the motor and can be used for system monitoring, early warning or automatic adjustment of the cooling system to prevent the motor from overheating. Through the temperature compensation strategy, the motor temperature under the stall condition is compensated to avoid the distortion of temperature acquisition under the stall condition, and a more accurate local maximum temperature of the motor can be collected, so that the thermal protection mechanism of the motor can be triggered normally to avoid motor burning. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0047] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0048] Figure 1 A flow chart of the first embodiment of the motor temperature compensation method of the present application;

[0049] Figure 2 This is a schematic diagram of three-phase alternating current under non-locked rotor conditions of this application;

[0050] Figure 3 This is a schematic diagram of three-phase direct current under the locked-rotor condition of this application;

[0051] Figure 4 This is a schematic diagram of the temperature compensation effect in the first embodiment of the motor temperature compensation method of the present application;

[0052] Figure 5 A brief flow chart of the motor temperature compensation method in this application;

[0053] Figure 6 This is a schematic diagram of the module structure of the motor temperature compensation device according to an embodiment of the present application;

[0054] Figure 7 Schematic diagram of the device structure of the hardware operating environment involved in the motor temperature compensation method in the embodiment of the present application.

[0055] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0056] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0057] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0058] The present application provides a method for motor temperature compensation. Figure 1 , Figure 1 This is a flow chart of the first embodiment of the motor temperature compensation method of the present application.

[0059] It should be noted that when the motor enters a stalled rotor condition, the three-phase current changes from AC to DC. Figure 2 It is a schematic diagram of three-phase alternating current under non-locked rotor conditions. The horizontal axis is the phase angle, the vertical axis is the maximum current value, and U, V, and W represent three symmetrical sinusoidal alternating currents with a phase difference of 120°. Among them, 0°, 90°, 180°, 270°, and 360° are the key sinusoidal angles. Figure 3 The following is a schematic diagram of three-phase direct current under a locked-rotor condition. The horizontal axis is the phase angle, and the vertical axis is the maximum current value. Under this locked-rotor condition, the three-phase current distribution is strongly correlated with the rotor pole position (i.e., the electrical angle). Even under the same torque conditions, the electrical angle is random, and the three-phase current size distribution is discrete, with one phase (U in the figure) having the largest current. The non-locked-rotor condition is alternating current, while the locked-rotor condition is direct current. The maximum current under the locked-rotor condition is 1.414 times that of the non-locked-rotor condition, which causes a certain phase to heat up severely when locked. Usually, for cost considerations, only 1 to 2 temperature sensors are arranged in the motor, so at most the temperature of the two-phase winding can be detected. Under the locked-rotor condition, there is a possibility that the temperature with the highest temperature relative to the temperature may be missed.

[0060] In this embodiment, the motor temperature compensation method includes steps S10 to S40:

[0061] Step S10, obtaining electrical parameters of the motor, and establishing a motor heating model of the motor under a stalled rotor condition based on the electrical parameters, wherein the motor heating model is used to calculate an actual temperature change of the motor caused by heating of winding copper loss under a stalled rotor condition;

[0062] It should be noted that electrical parameters refer to quantities that describe electrical performance and characteristics, such as voltage, current, resistance, capacitance, inductance, etc. In this application, the main electrical parameters that need to be considered are current, resistance, torque, etc. The establishment of the heating model is intended to simulate the heating behavior of the motor under stall conditions, especially the heat generated by the winding copper loss. Copper loss is mainly due to the thermal effect of current caused by the winding resistance. When stalled, since the motor does not rotate or hardly rotates, no or very little back electromotive force is generated, resulting in an increase in current, which intensifies the copper loss. In the motor heating model, Joule's law can be used , where I is the stall current and R is the winding resistance. The heating power of the winding is calculated. The heating accumulates over time, and the theoretical total heat can be obtained based on the product of the heating power and time. At the same time, the heat dissipation capacity of the motor also needs to be considered.

[0063] It is understandable that the actual temperature change of the motor winding due to copper loss under stall conditions can be calculated through the motor heating model. This calculation takes into account electrical parameters, including the current size and duration during stall and the resistance characteristics of the winding. The final temperature change is the key input in the motor temperature compensation algorithm.

[0064] Step S20, determining whether the motor needs temperature compensation according to the current torque state of the motor;

[0065] It should be noted that the stall state can be determined by torque monitoring and speed detection. When the motor is stalled, the output torque will approach or reach the maximum value. This is because the motor is trying to overcome excessive load or resistance, but fails to rotate the motor shaft. Therefore, real-time monitoring of the motor's output torque is the first step in determining stalling. The torque value can be estimated indirectly based on the torque sensor or by monitoring the motor current and voltage. In addition to torque, the motor speed is also an important indicator for determining the stall state. In the case of a stall, the motor speed will drop significantly, even close to zero. By monitoring the speed with a speed sensor installed on the motor shaft, it is possible to accurately determine whether the motor is in a stall.

[0066] It is understandable that comprehensive analysis of the motor's operating data, accurate judgment of whether the motor is in a stalled state, and decision on whether to start the temperature compensation process are important steps to ensure the motor's safe operation under extreme operating conditions and prevent overheating damage, thereby improving the flexibility and intelligence of the motor control strategy.

[0067] In a feasible implementation, step S20 may include steps S21 to S23:

[0068] Step S21, performing torque detection on the motor to determine whether the current torque of the motor is a stall torque;

[0069] It should be noted that the present application usually uses a torque sensor to directly measure the torsional torque of the motor output shaft. During the motor design or debugging stage, a stall torque threshold will be set based on factors such as the rated torque and overload capacity of the motor. This threshold is usually the critical point of the maximum output torque that the motor can withstand without being immediately damaged. After the control system receives the real-time torque data from the sensor, it compares it with the preset stall torque threshold. If the currently detected torque value reaches or exceeds the threshold, the system determines that the motor is in or close to a stall state.

[0070] Step S22, if the current torque is a stall torque, determining whether the motor speed is less than a preset stall speed;

[0071] It should be noted that, during the motor design or system configuration stage, a stall speed threshold is set based on the motor's characteristics, application requirements and other factors. This threshold is usually much lower than the minimum speed of the motor's normal operation to ensure accurate distinction when a stall occurs. After the system receives the signal from the speed sensor, it compares it with the preset stall speed threshold. If the currently detected speed is lower than this threshold, combined with the high torque state confirmed in step S21, it can be more certain that the motor is in or close to a stall state.

[0072] By checking the rotational speed, false alarms caused by single indicator judgment can be effectively avoided, ensuring that corresponding protection or compensation measures are only initiated when there is a real risk of stalling, reducing unnecessary system intervention and improving operational efficiency and stability.

[0073] In step S23, if the rotation speed of the motor is less than the preset stall speed, it is determined that the torque state is a stall state, and it is determined that the motor needs to be temperature compensated.

[0074] In this embodiment, the output torque of the motor is monitored in real time by a torque sensor and compared with the known maximum stall torque value. If the currently detected torque value is close to or equal to this maximum value, it is preliminarily determined that the motor may be in a stalled state. The actual speed of the motor is monitored by a speed sensor and compared with a preset stall speed threshold. The preset stall speed is usually a very low speed value, and below this value, the motor can be considered to be in a substantial stalled state. Based on the judgment of the first two steps, if the motor exhibits both high torque output (close to the stall torque) and the speed is lower than the set stall threshold, then it can be confirmed that the motor is in a stalled state. At this time, the heat generated by the copper loss and other effects inside the motor will accumulate rapidly, and measures need to be taken to prevent overheating. The system will activate the temperature compensation mechanism to ensure the long-term stable operation of the motor.

[0075] Step S30, if it is determined that the motor needs temperature compensation, the torque value of the motor under the stalled rotor condition is obtained, and the compensation temperature is determined according to the torque value and the motor heating model;

[0076] It should be noted that the torque value can be directly measured by a torque sensor or indirectly calculated based on electrical parameters such as the motor's current and voltage. The torque value is a key input variable in the motor heating model, which directly affects the current passing through the winding. When the motor is stalled, the higher the torque value, the greater the current, which leads to more heat. By substituting the actual torque value into the heating model, the increase in heat caused by copper loss can be more accurately predicted. In this application, the estimated torque can be used directly to represent the current.

[0077] It is understandable that accurate compensation temperature can reflect the additional heat generated by the motor due to stalling, thereby adding this compensation value based on the monitored motor temperature to ensure that the total temperature assessment is closer to the actual thermal state of the motor. Timely temperature compensation helps to start the cooling mechanism or take other protective measures to prevent the motor from being damaged due to overheating, extend the motor life, and ensure safe and stable operation of the system.

[0078] Step S40, obtaining a sampled temperature of a temperature sensor in the motor, and determining a local maximum temperature after temperature compensation according to the sampled temperature and the compensation temperature.

[0079] It should be noted that the motor is equipped with temperature sensors, which are installed in key positions of the motor, such as near the winding, bearings or other parts prone to heat. However, when the motor is blocked, there may be differences in the three-phase current, resulting in severe heating of one phase and uneven heating of the motor as a whole. If the position of the motor temperature sensor is not reasonable, it cannot reflect the current maximum temperature of the motor, and then cause the motor to burn out under extreme working conditions. Therefore, the sampled temperature may not be able to collect the true maximum temperature, and temperature compensation needs to be performed based on the sampled temperature according to the compensation temperature to obtain the final local maximum temperature.

[0080] refer to Figure 4 The schematic diagram of the temperature compensation effect of this embodiment is shown in the figure, where the horizontal axis represents time, including parts of normal working conditions and locked-rotor working conditions, and the vertical axis represents temperature. In the normal working condition stage, there is a certain difference between the temperature transfer temperature (sampling temperature) detected by the temperature sensor and the actual temperature of the motor, but there is no need to compensate for the temperature at this time; after entering the locked-rotor working condition, the temperature transfer temperature begins to be compensated. The three parabolas of the locked-rotor working condition part in the figure are the actual temperature of the motor, the temperature after temperature compensation, and the detected temperature transfer temperature from top to bottom. It can be seen that at the moment of the highest temperature, the difference between the temperature transfer temperature and the actual temperature of the motor is relatively large. It is obvious that the temperature transfer temperature collected at that time cannot be used to determine the activation of the thermal protection mechanism. After temperature compensation, the compensated temperature transfer temperature is closer to the actual temperature. Combined with the preset temperature difference range, the thermal protection mechanism can be triggered in time.

[0081] In this embodiment, the electrical parameters of the motor are obtained, and a motor heating model of the motor under a stalled rotor condition is established based on the electrical parameters. This model calculates the actual temperature change of the winding caused by copper loss, and determines whether the motor needs temperature compensation based on the current torque state of the motor. The compensation mechanism is activated only when it is confirmed that the motor is indeed in a stalled rotor and temperature compensation is necessary to avoid unnecessary resource consumption and misoperation. If it is determined that the motor needs temperature compensation, the torque value of the motor under the stalled rotor condition is obtained, and the compensation temperature is determined based on the torque value and the motor heating model. Once it is determined that compensation is required, the system will use the torque value and the previously established heating model to calculate the compensation temperature corresponding to the additional heat caused by the stall, obtain the sampling temperature of the temperature sensor in the motor, and determine the local maximum temperature after temperature compensation based on the sampling temperature and the compensation temperature. This local maximum temperature more accurately reflects the thermal state of the motor and can be used for system monitoring, early warning or automatic adjustment of the cooling system to prevent the motor from overheating. Through the temperature compensation strategy, the motor temperature under the stalled rotor condition is compensated, and the real temperature of the motor under the stalled rotor condition can be collected as much as possible, so as to accurately trigger the thermal protection mechanism of the motor. The motor will not be burned due to the failure to collect the highest temperature of the motor, and the motor performance will not be unable to be fully utilized due to the fixed-duration stall strategy.

[0082] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. On this basis, step S10 can include steps S11~S14:

[0083] Step S11, determining a temperature rise model in which the motor temperature rises due to heating caused by winding copper loss under a stalled-rotor condition;

[0084] It should be noted that when the motor is working, especially in the stalled condition, a large current will flow through the stator winding. Since the winding material is mainly copper, a certain amount of resistance loss will be generated when the current passes through. This part of energy is converted into heat energy, which is called "copper loss". The calculation formula of copper loss can be simplified as follows: , where I is the current flowing through the winding and R is the resistance of the winding. When the motor heats up, the heat will be dissipated to the surrounding environment through conduction, convection, and radiation. In order to accurately describe this process, it is necessary to determine a temperature rise model that can reflect the relationship between the temperature of the motor winding and the change of time and current. When determining the model, the heat dissipation conditions also need to be considered.

[0085] In a feasible implementation, step S11 may include steps S111-S112:

[0086] Step S111, determining the actual heat change of the motor under the condition of heating by the winding copper loss according to the heat generated by the heating by the winding copper loss and the heat dissipated by the motor, and there is a calculation relationship for the actual heat change:

[0087] ,

[0088] in, is the actual heat change, The heat generated by the copper loss of the winding. To dissipate heat from the motor;

[0089] There is a calculation formula for the heat generated by the copper loss of the motor winding:

[0090] ,

[0091] in, The maximum current value in the three-phase line under the locked-rotor condition, R is the copper loss resistance value of the three-phase line, and t is the time;

[0092] It should be noted that the actual heat change is the heat generated by the copper loss of the winding. Subtract the heat dissipated The heat generated during stalling mainly comes from the copper loss of the three-phase line, which is the product of the square of the three-phase alternating current, resistance and time.

[0093] Step S112, converting the current value I into a torque value It is expressed as, t is the unit time, and the model formula for the actual heat change in the unit time is:

[0094] ,

[0095] in, is the temperature rise per unit time, is the torque value, is the copper loss heating coefficient, is the heat dissipation coefficient, the copper loss heat generation coefficient and the heat dissipation coefficient are constants.

[0096] It should be noted that according to the simplified model, the heat generation , convert the current I into an expression based on torque, assuming that there is a conversion factor such that , it can be further simplified as, t It is a comprehensive coefficient that includes the resistance of the motor winding and the unit time inside the software. Simplified to a fixed value related to the motor cooling structure , which indicates the amount of heat that the motor can dissipate per unit time.

[0097] Temperature rise per unit time during stall It is equal to the difference between heat generation and heat dissipation divided by the heat capacity of the motor (considering the simplified treatment of heat capacity, it is directly expressed as temperature change), that is, , where C is the thermal capacity coefficient of the motor. For simplicity, we can ignore the specific calculation of the thermal capacity and directly use .

[0098] Step S12, determining a thermal model prototype corresponding to the electrical parameters, performing a motor locked-rotor condition test on the thermal model prototype, and obtaining multiple groups of test data generated during the test, wherein multiple thermocouples are attached to the thermal model prototype to detect the actual temperatures of different parts of the thermal model prototype, and the external cooling conditions during the test are the same as the external cooling conditions of the actual operating environment of the motor;

[0099] In a feasible implementation, step S12 may include steps S121 to S123:

[0100] Step S121, applying a stall torque to the thermal model prototype at different electrical angles, respectively, to obtain test data during the stall process at each electrical angle, wherein the test data includes a torque value, a test sampling temperature, a maximum actual temperature, and a torque request time;

[0101] It should be noted that a series of electrical angles must be selected for testing first. The selection of electrical angles usually covers the entire cycle of the motor operation, such as setting a test point every 30° or 45° to ensure full coverage of the motor's electrical cycle. The torque value is the size of the applied stall torque, and the test sampling temperature is the motor temperature sensor pre-buried in the key position of the prototype to continuously monitor the temperature change. The location of the motor temperature sensor is consistent with the motor in mass production status, and the temperature data during the test is recorded. The highest actual temperature is the highest temperature detected by multiple thermocouples, which is different from the test sampling temperature collected by the motor temperature sensor. The temperature detected by the thermocouple is the current actual maximum temperature of the motor. The torque request time is the time point when each stall test starts.

[0102] Step S122, calculating the temperature difference between the test sampling temperature and the highest actual temperature at each electrical angle, and determining the target electrical angle with the largest temperature difference according to the temperature difference corresponding to each electrical angle;

[0103] It should be noted that the electrical angles at which the temperature rise of the motor is most significant are determined. These angles may be locations where the heat dissipation conditions are poor or the heat accumulation effect is most serious.

[0104] For each test data at each electrical angle, calculate the difference between the test sampling temperature and the highest actual temperature. The test sampling temperature reflects the real-time temperature changes of the motor collected during the test, while the highest actual temperature is the actual highest temperature point during the test. Based on the comparison results of the temperature difference, the electrical angle with the largest temperature difference is selected as the target electrical angle. The target electrical angle means that the local heating is the most serious at this position.

[0105] Step S123, applying a plurality of different stall torques to the thermal model prototype at the target electrical angle, and obtaining a plurality of groups of test data in each stall process.

[0106] It should be noted that the target electrical angle determined in step S122 is the working condition where the motor exhibits the maximum temperature difference at a specific electrical angle. On this basis, S123 further refines the study of the thermal characteristics of the motor under this specific working condition by applying different stall torques. Different stall torques only apply stall torques to the thermal model prototype at the target electrical angle one by one according to a predetermined torque level sequence (such as 50%, 75%, 100%, 125% of the rated torque, etc.). During the application of each torque level, test data is continuously collected. By collecting detailed data at different torque levels, the heating model of the motor can be fitted more accurately, and the predictive ability and adaptability of the model can be improved, especially in extreme working conditions such as stall.

[0107] In a feasible implementation, step S123 may include steps A10 to A20:

[0108] Step A10, obtaining a preset initial electrical angle, using the preset initial electrical angle as a simulated electrical angle, and applying a stall torque to the thermal model prototype based on the simulated electrical angle until the actual temperature of the motor collected by each thermocouple in the thermal model prototype reaches a preset maximum temperature of the thermal model prototype;

[0109] It should be noted that the preset initial electrical angle is based on the motor design and working characteristics, and a representative electrical angle is selected as the starting point of the simulation. By adjusting the applied torque or test time, the actual temperature of the thermal model prototype collected by the thermocouple gradually approaches the maximum temperature of the motor design, and ensure that the difference between this temperature and the maximum temperature of the motor design is kept within the preset temperature difference range (such as ±5°C).

[0110] The selected initial electrical angle is applied to the thermal model prototype. The electrical angle of the motor is fixed at this set value to simulate a specific magnetic field distribution and current flow. At the set electrical angle, a stall torque is applied to the thermal model prototype to simulate the working state of the motor under a stall condition. The stall torque is usually close to or equal to the maximum stall torque of the motor to create the worst heating conditions, so that the thermal model prototype reaches a preset ideal initial thermal state, providing a unified and reliable starting condition for the subsequent establishment of a temperature compensation model.

[0111] Step A20, obtaining the torque value of the stall torque, determining the test sampling temperature collected by the temperature sensor in the thermal model prototype, determining the actual temperature collected by each thermocouple in the thermal model prototype, and determining the highest actual temperature with the highest temperature from each actual temperature, obtaining the torque request time during the stall process, and using the torque value, the test sampling temperature, the highest actual temperature and the torque request time as test data for the simulated electrical angle;

[0112] It should be noted that the torque value is the output torque of the motor under stall conditions, the test sampling temperature is the temperature data of the motor fixed monitoring point continuously or regularly collected by the temperature sensor during the stall test, the highest actual temperature is the actual highest temperature measured by the thermocouple with high precision, and the location of the thermocouple is the hottest area inside the motor, and the torque request time refers to the specific moment when the motor starts to try to overcome the stall load, that is, the stall torque begins to be applied. Collecting the key parameters of the motor under stall conditions provides detailed data support for the subsequent thermal model establishment and optimization.

[0113] Step A30, increasing the simulated electrical angle based on the preset growth electrical angle, and returning to the execution step: applying a stall torque to the thermal model prototype based on the simulated electrical angle until the actual temperature of the motor collected by each thermocouple in the thermal model prototype reaches the preset maximum temperature of the thermal model prototype.

[0114] It should be noted that the preset increase in electrical angle is a fixed electrical angle increment, such as 30°, which needs to ensure that the key angles within the full operating range of the motor are covered.

[0115] Based on the initial electrical angle, the simulated electrical angle is gradually increased according to the preset growth electrical angle. After each increase, the working state of the motor represented by the simulated electrical angle changes accordingly. For each new simulated electrical angle, the operation of step A20 is repeated, that is, the stall torque is applied to the thermal model prototype, and the corresponding torque value, test sampling temperature, maximum actual temperature and torque request time and other key data are monitored and recorded at the same time. As the electrical angle increases, the collected data forms a series of data sets of electrical angles and corresponding heating characteristics. This step continues until the preset electrical angle upper limit is reached or all preset angle steps are completed, thereby covering all key electrical angles within the working range of the motor, thereby obtaining the most comprehensive heating data.

[0116] This implementation method applies a stall torque to the thermal model prototype at a series of selected electrical angles to simulate the working conditions when the motor is stalled at these specific positions. Through experiments, data such as torque value, motor temperature sensor sampling temperature, maximum actual temperature, and torque request time are recorded. The test data recorded at each electrical angle are analyzed, the temperature difference between the motor temperature sensor sampling temperature and the maximum actual temperature is calculated, and the electrical angle with the largest temperature difference is identified, which is designated as the target electrical angle. Find out which electrical angle has the largest temperature difference inside the motor among all the test electrical angles. This temperature difference can be regarded as an indirect reflection of the heat transfer efficiency of the motor at this electrical angle. Apply multiple different stall torques to the thermal model prototype at the target electrical angle, repeat the simulation experiment, and record multiple sets of test data during each stall process. Through this series of experiments, a detailed database on the relationship between the stall torque and the heating effect at the target electrical angle can be constructed, providing more accurate data support for the subsequent establishment of the motor heating model.

[0117] Step S13, fitting the copper loss heating coefficient and the heat dissipation coefficient according to the test data and the temperature rise model;

[0118] It should be noted that in step S12, multiple groups of test data are obtained through experiments on the thermal model prototype under simulated stalled rotor conditions, and the temperature rise model is a mathematical expression based on physical principles, which describes the rising trend of the motor winding temperature over time, taking into account factors such as copper loss heating and heat dissipation efficiency. After normalizing each group of test data, the test data is substituted into the temperature rise model using a mathematical method, and the error between the temperature change curve predicted by the model and the actual test data is minimized by adjusting the copper loss heating coefficient and the heat dissipation coefficient.

[0119] The copper loss heating coefficient and heat dissipation coefficient obtained by fitting the test data can more accurately reflect the thermal characteristics of the motor under actual working conditions, improve the accuracy of the temperature compensation model, and help design a more effective temperature control strategy.

[0120] Step S14, establishing a motor heating model according to the copper loss heating coefficient, the heat dissipation coefficient and the temperature rise model.

[0121] Before starting this step, two key parameters have been obtained through experiments and data analysis: copper loss heating coefficient and heat dissipation coefficient. The copper loss heating coefficient describes the thermal effect generated when current passes through the winding, and is the heating term in the model. The heat dissipation coefficient represents the ability of the motor to dissipate heat, and is the heat dissipation term in the model. It is related to factors such as ambient temperature, cooling medium, and motor structure. At the same time, there is also a temperature rise model based on theoretical and experimental verification, which summarizes the law of motor temperature change over time and takes into account the balance of heating and heat dissipation.

[0122] It can be understood that based on the temperature rise model, the copper loss heating coefficient and the heat dissipation coefficient are integrated to form a more specific mathematical expression, and a mathematical model that accurately reflects the heat generation characteristics of the motor during stalling is established. This model can predict the temperature change of the motor under stalling conditions and provide a basis for the temperature compensation strategy, thereby compensating the sampling temperature of the temperature sensor in the motor.

[0123] In this embodiment, firstly, based on the motor theory and thermodynamic principles, a temperature rise model is determined that can describe the increase in motor temperature caused by winding copper loss under stalled rotor conditions, which can reflect the temperature change law, and a thermal model prototype with the same thermal characteristics as the actual motor is made. Multiple thermocouples are arranged at key positions of the prototype. During the test, the external cooling conditions are kept consistent with the actual operating environment, and the prototype is tested to obtain test data. The copper loss heating coefficient and heat dissipation coefficient are determined by mathematical fitting using the collected multiple sets of test data and the preset motor temperature change formula. According to the obtained copper loss heating coefficient and heat dissipation coefficient, the heating model of the motor under stalled rotor conditions is formally established. This model can input the torque of the motor and output the expected temperature change or heat accumulation, providing a basis for the subsequent temperature compensation strategy. The model can accurately predict the temperature change of the motor, thereby obtaining an accurate compensation temperature.

[0124] Based on the first embodiment of the present application, in the third embodiment of the present application, the same or similar contents as those in the first embodiment can be referred to the above description, and will not be described in detail later. On this basis, step S30 can include steps S31 to S33:

[0125] Step S31, obtaining the duration of the motor being in a stalled state;

[0126] Step S32, inputting the torque value into the motor heating model to obtain a first compensation temperature per unit time;

[0127] It should be noted that based on the heating model, the expected increase in temperature inside the motor per unit time under the current torque condition is calculated, that is, the first compensation temperature. Since temperature compensation is accumulated over time, the first compensation temperature needs to be recalculated based on the latest torque value every time unit (such as one second, one minute, etc.) passes, and is accumulated into the total compensation temperature.

[0128] Step S33, accumulating the first compensation temperature of each unit time within the duration to obtain the compensation temperature at the current moment.

[0129] It should be noted that in In the example, t is the unit time, which can be equivalent to Temperature rise per unit time , so the rearranged formula is:

[0130]

[0131] The compensation temperature at the nth moment during the stall process is:

[0132]

[0133] Superimposed on the sampled temperature of the temperature sensor The local maximum temperature after for:

[0134]

[0135] That is, the estimated actual hottest temperature of the motor = the sampling temperature of the temperature sensor + temperature compensation.

[0136] In this embodiment, the duration from the start of the stall to the current moment is recorded, and the temperature increment that the motor should theoretically compensate for each unit time (such as seconds or minutes) is calculated based on the current stall torque and the motor heating model. The compensated temperatures calculated in each unit time are added up to obtain the total compensated temperature that should be accumulated from the start of the stall to the present. This is used as the temperature value that the motor should additionally compensate for at the current moment, thereby realizing dynamic calculation of temperature compensation under motor stall conditions, ensuring that the compensation strategy can be adjusted with changes in the stall time and intensity, and improving the accuracy and efficiency of temperature management.

[0137] Based on the third embodiment of the present application, in the fourth embodiment of the present application, the same or similar contents as those in the third embodiment can be referred to the above description, and will not be described in detail later. On this basis, after step S33, steps S34 to S36 can be included:

[0138] Step S34, obtaining the current electrical angle of the motor and the target electrical angle corresponding to the motor heating model;

[0139] It should be noted that the electrical angle of the motor directly affects the current distribution and the magnetic field inside the motor, which in turn affects the heating characteristics. The current electrical angle is obtained in order to more accurately adjust the compensation strategy in the subsequent steps to match it with the actual operating state of the motor.

[0140] Step S35, determining a correction factor for compensating temperature according to the current electrical angle and the target electrical angle, wherein the correction factor represents the current change ratio at the current electrical angle relative to the target electrical angle, and the calculation formula of the correction factor is expressed as:

[0141] ,

[0142] in, is the current electrical angle, is the target electrical angle;

[0143] It should be noted that the target electrical angle is the target electrical angle determined in step S122, and the target electrical angle corresponds to a set of copper loss heating coefficients and heat dissipation coefficients. At different electrical angles, the heating characteristics of the motor will be different, especially the copper loss heating is significantly affected by the current. By introducing a correction factor, the previous compensation temperature can be adjusted according to the current electrical angle to better fit the actual heating situation of the motor at a specific electrical angle.

[0144] The current inside the motor changes with the electrical angle, causing the heating condition to change accordingly. The absolute value of the cosine function ranges from [0, 1]. The value reflects the relative position relationship between the current electrical angle and the target electrical angle. When it approaches θ, Close to 1, it means that the current angle is close to the target angle and temperature compensation needs to be performed normally; keep away When , the cos value decreases, indicating that the compensation temperature needs to be reduced proportionally according to the difference in heating characteristics at the current position to adapt to the changes in heating characteristics caused by changes in electrical angle.

[0145] Step S36, correcting the compensation temperature according to the correction factor to determine the corrected compensation temperature.

[0146] exist Figure 3 In the case shown, the motor temperature sensor is arranged on the U or W phase, and the temperature of the U phase with the highest heat generation cannot be collected at this time. In step S13, according to the case, the target electrical angle corresponding to the U phase current is The fitted and The U-phase temperature can be compensated correctly, but when the angle changes, it will cause over-compensation. Therefore, it is necessary to correct the compensation value according to the sinusoidal characteristics of the three-phase current, that is, multiply the compensation temperature by a in is the current angle.

[0147] In this embodiment, the current position of the motor rotor is monitored and reported in real time through the built-in position sensor of the motor (such as an encoder, a resolver, etc.), so as to obtain the current electrical angle value, and determine the correction factor according to the current electrical angle and the target electrical angle. The calculated correction factor is applied to the previously determined compensation temperature, and the ratio is adjusted to obtain the corrected compensation temperature, thereby ensuring that the compensation measures can adapt to the actual heating conditions of the motor at different electrical angles, making the temperature compensation more accurate, and helping the motor to maintain the best thermal management state under various operating conditions, reducing the risk of overheating, and improving the reliability and efficiency of the motor operation.

[0148] For example, in order to help understand the implementation process of the motor temperature compensation method obtained by combining this embodiment with the above-mentioned embodiment 1, please refer to Figure 5 , Figure 5 A brief flow chart of a motor temperature compensation method is provided, specifically:

[0149] After the process starts, it is determined whether there is a torque request. If so, the process proceeds to the next part of vehicle speed determination. If not, it means that the vehicle currently does not have torque. During the operation, the entire process ends, corresponding to step S21;

[0150] When judging the vehicle speed, it is judged whether the vehicle speed is greater than 0.5 km / h, where 0.5 km / h is a preset speed threshold. If so, it is not necessary to calculate the compensation temperature, and the motor temperature sampled by the PTC (Positive Temperature Coefficient) is directly used to enter the next part of the judgment; if not, it is determined that the current is a stall torque, the compensation temperature is calculated, and the sum of the motor temperature sampled by the PTC and the compensation temperature is used as the motor PTC compensated temperature, and the next part of the judgment is performed based on the motor compensated temperature, corresponding to step S22;

[0151] Determine whether the motor temperature after PTC compensation (when compensation is required) or the motor temperature sampled by PTC (when compensation is not required) is less than the motor over-temperature protection threshold. If so, there is no need to trigger the thermal protection mechanism and the entire process ends; if not, the thermal protection mechanism is triggered, the motor is derated, and finally the entire process ends, corresponding to step S40.

[0152] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the motor temperature compensation method of the present application. More simple transformations based on this technical concept are all within the protection scope of the present application.

[0153] This application also provides a motor temperature compensation device, please refer to Figure 6, the motor temperature compensation device comprises:

[0154] A model module 10 is used to obtain electrical parameters of the motor, and to establish a motor heating model of the motor under a stalled rotor condition based on the electrical parameters, wherein the motor heating model is used to calculate an actual temperature change of the motor caused by heating of winding copper loss under a stalled rotor condition;

[0155] A judgment module 20, used to determine whether the motor needs temperature compensation according to the current torque state of the motor;

[0156] The calculation module 30 is used for obtaining the torque value of the motor under the stall condition if it is determined that the motor needs temperature compensation, and determining the compensation temperature according to the torque value and the motor heating model;

[0157] The compensation module 40 is used to obtain the sampled temperature of the temperature sensor in the motor, and determine the local maximum temperature after temperature compensation according to the sampled temperature and the compensation temperature.

[0158] The motor temperature compensation device provided by the present application adopts the motor temperature compensation method in the above embodiment, which can solve the technical problem that the permanent magnet synchronous motor is prone to temperature acquisition distortion under the stall condition and cannot acquire the local maximum temperature of the motor. Compared with the prior art, the beneficial effects of the motor temperature compensation device provided by the present application are the same as the beneficial effects of the motor temperature compensation method provided by the above embodiment, and the other technical features in the motor temperature compensation device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0159] The present application provides a motor temperature compensation device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the motor temperature compensation method in the above-mentioned embodiment one.

[0160] Reference below Figure 7 , which shows a schematic diagram of the structure of a motor temperature compensation device suitable for implementing the embodiment of the present application. The motor temperature compensation device in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 7 The motor temperature compensation device shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0161] like Figure 7 As shown, the motor temperature compensation device may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the xxx device are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the motor temperature compensation device to communicate with other devices wirelessly or by wire to exchange data. Although the figure shows a motor temperature compensation device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have alternatively.

[0162] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0163] The motor temperature compensation device provided by the present application adopts the motor temperature compensation method in the above embodiment, which can solve the technical problem that the permanent magnet synchronous motor is prone to temperature acquisition distortion under the stall condition and cannot acquire the local maximum temperature of the motor. Compared with the prior art, the beneficial effects of the motor temperature compensation device provided by the present application are the same as the beneficial effects of the motor temperature compensation method provided by the above embodiment, and the other technical features in the motor temperature compensation device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0164] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0165] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0166] The present application also provides a storage medium, which includes a computer-readable storage medium, and the computer-readable storage medium stores one or more programs. The one or more programs can also be executed by one or more processors to implement the steps of each embodiment of the above-mentioned motor temperature compensation method.

[0167] The specific implementation of the computer-readable storage medium of the present invention is basically the same as the above-mentioned embodiments of the motor temperature compensation method, and will not be described in detail here.

[0168] The present application also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of the motor temperature compensation method as described above are implemented.

[0169] The computer program product provided by the present application can solve the technical problem that the permanent magnet synchronous motor is prone to temperature acquisition distortion under the stall condition and cannot acquire the local maximum temperature of the motor. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the motor temperature compensation method provided by the above embodiment, which will not be repeated here.

[0170] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A motor temperature compensation method, characterized in that: The motor temperature compensation method comprises: Acquire electrical parameters of the motor, and establish a motor heating model of the motor under a stalled rotor condition based on the electrical parameters, wherein the motor heating model is used to calculate an actual temperature change of the motor caused by heating of winding copper loss under the stalled rotor condition; Determining whether the motor needs temperature compensation according to the current torque state of the motor; If it is determined that the motor needs temperature compensation, obtaining the torque value of the motor under a stalled rotor condition, and determining a compensation temperature according to the torque value and the motor heating model; Acquire a sampled temperature of a temperature sensor in the motor, and determine a local maximum temperature after temperature compensation according to the sampled temperature and the compensation temperature; Wherein, the step of establishing a motor heating model under a stalled rotor condition based on the electrical parameters comprises: Determine the temperature rise model of the motor caused by the heating of the winding copper loss under the stall condition; Determine a thermal model prototype corresponding to the electrical parameters, perform a motor locked-rotor condition test on the thermal model prototype, and obtain multiple groups of test data generated during the test, wherein multiple thermocouples are attached to the thermal model prototype to detect the actual temperature of different parts of the thermal model prototype, and the external cooling conditions during the test are the same as the external cooling conditions of the actual operating environment of the motor; Fitting the copper loss heating coefficient and the heat dissipation coefficient according to the test data and the temperature rise model; Establishing a motor heating model according to the copper loss heating coefficient, the heat dissipation coefficient and the temperature rise model; The step of performing a motor stall condition test on the thermal model prototype and acquiring multiple groups of test data generated during the test includes: Applying a stall torque to the thermal model prototype at different electrical angles to obtain test data during the stall process at each electrical angle, wherein the test data includes a torque value, a test sampling temperature, a maximum actual temperature, and a torque request time; Calculate the temperature difference between the test sampling temperature and the highest actual temperature at each electrical angle, and determine the target electrical angle with the largest temperature difference according to the temperature difference corresponding to each electrical angle; A plurality of different stall torques are applied to the thermal model prototype at the target electrical angle to obtain a plurality of groups of test data in each stall process.

2. The motor temperature compensation method according to claim 1, characterized in that: The step of applying the stall torque to the thermal model prototype at different electrical angles to obtain test data during the stall process at each electrical angle includes: Obtaining a preset initial electrical angle, using the preset initial electrical angle as a simulated electrical angle, and applying a stall torque to the thermal model prototype based on the simulated electrical angle until the actual temperature of the motor collected by each thermocouple in the thermal model prototype reaches a preset maximum temperature of the thermal model prototype; Obtaining a torque value of the stall torque, determining a test sampling temperature collected by a temperature sensor in the thermal model prototype, determining actual temperatures collected by each thermocouple in the thermal model prototype, and determining a highest actual temperature with the highest temperature from each actual temperature, obtaining a torque request time during the stall process, and using the torque value, the test sampling temperature, the highest actual temperature, and the torque request time as test data for the simulated electrical angle; The simulated electrical angle is incremented based on a preset growth electrical angle, and the execution step is returned to: a stall torque is applied to the thermal model prototype based on the simulated electrical angle until the actual temperature of the motor collected by each thermocouple in the thermal model prototype reaches a preset maximum temperature of the thermal model prototype.

3. The motor temperature compensation method according to claim 1, characterized in that: The step of determining whether the motor needs to be temperature compensated according to the current torque state of the motor comprises: Performing torque detection on the motor to determine whether the current torque of the motor is a stall torque; If the current torque is a stall torque, determining whether the speed of the motor is less than a preset stall speed; If the rotation speed of the motor is less than the preset stall speed, it is determined that the torque state is a stall state, and it is determined that the motor needs to be temperature compensated.

4. The motor temperature compensation method according to claim 3, characterized in that: The step of determining the compensation temperature according to the torque value and the motor heating model comprises: Obtaining the duration of the motor being in a stalled state; Inputting the torque value into the motor heating model to obtain a first compensation temperature per unit time; The first compensation temperature of each unit time within the duration is accumulated to obtain the compensation temperature at the current moment.

5. The motor temperature compensation method according to claim 4, characterized in that: After the step of accumulating the first compensation temperature of each unit time within the duration to obtain the compensation temperature at the current moment, the method further includes: Acquire the current electrical angle of the motor and the target electrical angle corresponding to the motor heating model; The correction factor of the compensation temperature is determined according to the current electrical angle and the target electrical angle, wherein the correction factor represents the current change ratio relative to the target electrical angle at the current electrical angle, and the calculation formula of the correction factor is expressed as: ,in, is the current electrical angle, is the target electrical angle; The compensation temperature is corrected according to the correction factor to determine a corrected compensation temperature.

6. A motor temperature compensation device, characterized in that: The motor temperature compensation device comprises: A model module, used to obtain electrical parameters of the motor, and to establish a motor heating model of the motor under a stalled rotor condition based on the electrical parameters, wherein the motor heating model is used to calculate an actual temperature change of the motor caused by heating of winding copper loss under the stalled rotor condition; A judgment module, used for determining whether the motor needs temperature compensation according to the current torque state of the motor; A calculation module, for obtaining a torque value of the motor under a stalled condition if it is determined that the motor needs temperature compensation, and determining a compensation temperature according to the torque value and a heating model of the motor; A compensation module, used for acquiring a sampled temperature of a temperature sensor in the motor, and determining a local maximum temperature after temperature compensation according to the sampled temperature and the compensation temperature; Wherein, the model module is specifically used for: Determine the temperature rise model of the motor caused by the heating of the winding copper loss under the stall condition; Determine a thermal model prototype corresponding to the electrical parameters, perform a motor locked-rotor condition test on the thermal model prototype, and obtain multiple groups of test data generated during the test, wherein multiple thermocouples are attached to the thermal model prototype to detect the actual temperature of different parts of the thermal model prototype, and the external cooling conditions during the test are the same as the external cooling conditions of the actual operating environment of the motor; Fitting the copper loss heating coefficient and the heat dissipation coefficient according to the test data and the temperature rise model; Establishing a motor heating model according to the copper loss heating coefficient, the heat dissipation coefficient and the temperature rise model; Wherein, the model module is specifically used for: Applying a stall torque to the thermal model prototype at different electrical angles to obtain test data during the stall process at each electrical angle, wherein the test data includes a torque value, a test sampling temperature, a maximum actual temperature, and a torque request time; Calculate the temperature difference between the test sampling temperature and the highest actual temperature at each electrical angle, and determine the target electrical angle with the largest temperature difference according to the temperature difference corresponding to each electrical angle; A plurality of different stall torques are applied to the thermal model prototype at the target electrical angle to obtain a plurality of groups of test data in each stall process.

7. A motor temperature compensation device, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the motor temperature compensation method according to any one of claims 1 to 5.

8. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the motor temperature compensation method according to any one of claims 1 to 5 are implemented.

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