Electric motor stalling protection method and apparatus, and controller and storage medium

Abstract

Provided in the embodiments of the present application are an electric motor stalling protection method and apparatus, and a controller and a storage medium. The method comprises: acquiring the current electric motor temperature, the current electric motor speed, the current electric motor torque and the current electric motor controller temperature; on the basis of the electric motor torque and the electric motor speed, determining an operation state of an electric motor, wherein the operation state comprises a stalling state and a non-stalling state; if the operation state of the electric motor is the stalling state, calculating a first count value on the basis of the electric motor temperature, and calculating a second count value on the basis of the electric motor controller temperature; and on the basis of the operation state of the electric motor, the first count value and the second count value, executing a target stalling protection policy. Over-temperature protection threshold values are set for two devices, i.e., an electric motor and an electric motor controller, and the temperatures of the two devices are monitored in real time, so as to protect the two devices; and a main control chip with very high computing power is not required, and the range of applications is relatively wide.

Description

Motor stall protection method, device, controller and storage medium

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on November 7, 2023, with application number 202311476258.4 and application name “Motor stall protection method, device, controller and storage medium”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of automotive technology, and in particular to a motor stall protection method, device, controller, and storage medium. Background Art

[0003] New energy vehicles are booming. Most domestic new energy vehicles use power batteries as their power source and are equipped with permanent magnet synchronous motors (PMSMs) as their drive systems. Permanent magnet synchronous motors (PMSMs) often experience stalled rotors during driving. These stalls can occur when starting on a hill, when the driver forgets to release the parking brake, when the brake system fails, or when the drive system is damaged. When a stall occurs, the current in the power drive system rises sharply, generating significant heat. If this condition persists for an extended period, it can damage the motor or motor controller. Therefore, stall protection is essential for motor protection.

[0004] In related technologies, the stall protection method usually sets a motor over-temperature protection threshold or a motor controller over-temperature protection threshold, calculates heat loss through current, switching frequency, etc., and estimates the real-time temperature of the motor or motor controller. When the temperature of the motor or motor controller exceeds the preset over-temperature protection threshold, the current is limited to achieve the purpose of protecting the device.

[0005] However, the above-mentioned stall protection method usually only sets the over-temperature protection threshold of a single device and cannot provide protection for other devices. For example, the over-temperature protection threshold of the motor controller is set separately without setting the over-temperature protection threshold of the motor. In this case, the motor cannot be protected. In addition, estimating the real-time temperature of the motor or motor controller requires a high level of computing power from the main control chip, and its scope of application is not wide.

[0006] It should be pointed out that the information disclosed in the background technology section of this application is only intended to deepen the understanding of the general background technology of this application, and should not be regarded as an admission or any form of implication that the information constitutes prior art already known to those skilled in the art.

[0007] Summary of the Invention

[0008] In view of this, the present application provides a motor stall protection method to help solve the problem in the prior art that only the over-temperature protection threshold of a single device is set, which cannot provide protection for other devices, and the estimating the real-time temperature of the device requires a high computing power of the main control chip and has a limited scope of application.

[0009] In a first aspect, an embodiment of the present application provides a motor stall protection method, comprising:

[0010] Get the current motor temperature, motor speed, motor torque and motor controller temperature;

[0011] Determining a working state of the motor according to the motor torque and the motor speed, wherein the working state includes a stalled state and a non-stalled state;

[0012] If the working state of the motor is a stalled state, a first count value is calculated according to the motor temperature, and a second count value is calculated according to the motor controller temperature;

[0013] A target stall protection strategy is executed according to the working state of the motor, the first count value, and the second count value.

[0014] In a possible implementation, determining the operating state of the motor according to the motor torque and the motor speed includes:

[0015] If the motor torque is greater than a preset motor torque threshold and the motor speed is less than a preset motor speed threshold, determining that the working state of the motor is a stalled state;

[0016] If the motor torque is equal to 0 or the motor speed is greater than or equal to the motor speed threshold, it is determined that the working state of the motor is a non-stall state.

[0017] In a possible implementation, if the motor torque is equal to 0 or the motor speed is greater than or equal to the motor speed threshold, determining that the working state of the motor is a non-stalled state includes:

[0018] If the motor torque is equal to 0 or the motor speed is greater than or equal to the motor speed threshold, determining whether the working state of the motor is a stalled state;

[0019] If the working state of the motor is a stalled state, the working state of the motor is adjusted to a non-stalled state.

[0020] In a possible implementation, if the working state of the motor is a stalled state, calculating a first count value according to the motor temperature includes:

[0021] If the working state of the motor is a stalled state, the motor counter is controlled to start counting and calculate the motor temperature rise;

[0022] The first count value is calculated according to the count value of the motor counter, the motor temperature, and the motor temperature rise.

[0023] In a possible implementation, if the working state of the motor is a stalled state, calculating the second count value according to the temperature of the motor controller includes:

[0024] If the working state of the motor is a stalled state, the motor controller counter is controlled to start counting and calculate the temperature rise of the motor controller;

[0025] The second count value is calculated according to the count value of the motor controller counter, the motor controller temperature, and the temperature rise of the motor controller.

[0026] In a possible implementation, executing a target stall protection strategy according to the working state of the motor, a count value of the motor counter, and a count value of the motor controller counter includes:

[0027] If the working state of the motor is a stalled state, executing a target stall protection strategy according to the first count value and / or the second count value;

[0028] If the working state of the motor is a non-stalled rotor state, whether to exit the stall protection strategy is determined according to the first count value and / or the second count value.

[0029] In a possible implementation, if the working state of the motor is a stalled state, executing a target stall protection strategy according to the first count value and / or the second count value includes:

[0030] If the working state of the motor is a stalled state, and the first count value and / or the second count value is greater than a first threshold, executing a first-level stall protection strategy;

[0031] If the working state of the motor is a stalled state, and the first count value and / or the second count value is greater than a second threshold value, executing a secondary stall protection strategy;

[0032] The first threshold is smaller than the second threshold, and the protection level of the first-level stall protection strategy is lower than that of the second-level stall protection strategy.

[0033] In a possible implementation, if the working state of the motor is a non-stalled-rotor state, determining whether to exit the stall protection strategy according to the first count value and / or the second count value includes:

[0034] If the working state of the motor is a non-stall state, and the first count value and / or the second count value is greater than a third threshold, executing a third-level stall protection strategy;

[0035] If the working state of the motor is a non-stall state, and the first count value and / or the second count value is less than or equal to a third threshold, then exiting the execution of the stall protection strategy;

[0036] The third threshold is smaller than the first threshold, and the protection level of the third-level stall protection strategy is lower than that of the first-level stall protection strategy.

[0037] In one possible implementation, if the working state of the motor is a non-stall state and the first count value and / or the second count value is greater than a third threshold, executing a three-level stall protection strategy includes:

[0038] If the working state of the motor is a non-stall state, the first count value and / or the second count value is greater than a third threshold, and the currently executed stall protection strategy is the second-level stall protection strategy, then the third-level stall protection strategy is executed;

[0039] If the working state of the motor is a non-stall state, the first count value and / or the second count value is greater than a third threshold, and the currently executed stall protection strategy is the first-level stall protection strategy or the third-level stall protection strategy, then the stall protection strategy is exited.

[0040] In one possible implementation,

[0041] The first-level stall protection strategy includes: reducing the carrier frequency of the motor controller;

[0042] The secondary stall protection strategy includes: reducing the carrier frequency of the motor controller and limiting the limit value of the motor torque to a first limit value;

[0043] The three-level stall protection strategy includes: setting the carrier frequency of the motor controller to a normal carrier frequency, and limiting the limit value of the motor torque to a second limit value;

[0044] The first limit value is less than or equal to the second limit value.

[0045] In one possible implementation,

[0046] The first limit value is the rated torque;

[0047] The second limit value increases gradually during the execution of the three-level stall protection strategy.

[0048] In a second aspect, an embodiment of the present application provides a motor stall protection device, comprising:

[0049] The acquisition module is used to obtain the current motor temperature, motor speed, motor torque and motor controller temperature;

[0050] A working state determining module, configured to determine a working state of the motor according to the motor torque and the motor speed, wherein the working state includes a stalled state and a non-stalled state;

[0051] a calculation module, configured to calculate a first count value according to the motor temperature and a second count value according to the motor controller temperature if the working state of the motor is a stalled state;

[0052] An execution module is used to execute a target stall protection strategy according to the working state of the motor, the first count value and the second count value.

[0053] In a third aspect, an embodiment of the present application provides a controller, including:

[0054] processor;

[0055] Memory;

[0056] and a computer program, wherein the computer program is stored in the memory, and the computer program comprises instructions, which, when executed by the processor, enable the electronic device to perform the method in the first aspect.

[0057] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, which includes a stored program, wherein when the program is running, the device where the computer-readable storage medium is located is controlled to execute the method in the first aspect.

[0058] By adopting the solution provided in the embodiment of the present application, over-temperature protection thresholds of the motor and the motor controller are set, and the temperatures of the motor and the motor controller are monitored in real time to achieve protection of the motor and the motor controller. This solution does not require a main control chip with high computing power and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0060] FIG1 is a flow chart of a motor stall protection method provided in an embodiment of the present application;

[0061] FIG2 is a schematic structural diagram of a motor stall protection device provided in an embodiment of the present application;

[0062] FIG3 is a flow chart of another motor stall protection method provided in an embodiment of the present application;

[0063] FIG4 is a schematic diagram of the structure of a controller provided in an embodiment of the present application. DETAILED DESCRIPTION

[0064] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0065] It should be clear that the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0066] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0067] It should be understood that the term "and / or" as used herein simply describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. Furthermore, the character " / " in this document generally indicates an "or" relationship between the associated objects.

[0068] New energy vehicles are booming. Most domestic new energy vehicles use batteries as their power source and are equipped with permanent magnet synchronous motors (PMSMs) as their drive systems. Permanent magnet synchronous motors (PMSMs) often experience stalled rotor conditions during driving. When a stall occurs, the current in the drive system rises sharply, generating significant heat. Over time, this condition can damage the motor or motor controller. Therefore, stall protection is essential for motor protection.

[0069] In the prior art, stall protection methods typically set a motor over-temperature protection threshold or a motor controller over-temperature protection threshold, calculate heat loss through current, switching frequency, and other factors, and estimate the real-time temperature of the motor or motor controller. When the temperature of the motor or motor controller exceeds the preset over-temperature protection threshold, the current is limited to achieve the purpose of protecting the device. However, in the prior art, the over-temperature protection threshold is usually only set for a single device, the motor or motor controller, and no protection is provided for other devices. For example, if the over-temperature protection threshold of the motor controller is set separately without setting the over-temperature protection threshold of the motor, the motor will not be protected in this case. In addition, estimating the real-time temperature of the motor or motor controller requires a high level of computing power from the main control chip and a stable ambient temperature, which limits its application range.

[0070] To address the above issues, embodiments of the present application provide a motor stall protection method. This method protects both the motor and the motor controller by setting overtemperature protection thresholds and monitoring their temperatures in real time. This method does not require a high-performance main control chip and has a wide range of applications. This is described in detail below.

[0071] Referring to FIG1 , which is a flow chart of a motor stall protection method provided in an embodiment of the present application, the method mainly includes the following steps:

[0072] Step S101: Acquire the current motor temperature, motor speed, motor torque and motor controller temperature.

[0073] In the embodiments of the present application, the motor temperature and the motor controller temperature are periodically collected by a motor temperature sensor and a motor controller temperature sensor. A person skilled in the art can set the collection period to any length, such as 1 second, 1 millisecond, or other lengths, based on practical circumstances. A longer collection period can reduce the load on the motor and motor controller. A shorter collection period can make the motor temperature and the motor controller temperature more accurate, thereby making subsequent calculation results more accurate.

[0074] Specifically, the current motor temperature, motor speed, motor torque and motor controller temperature are collected in real time to facilitate the subsequent determination of the motor's operating status and further implementation of the target stall protection strategy.

[0075] Step S102: Determine the working state of the motor according to the motor torque and the motor speed.

[0076] Motor stall is a situation in which the motor still outputs torque at a very low speed. Therefore, it is possible to determine whether the motor is in a stalled state by comparing the motor torque and motor speed with the preset motor torque threshold and motor speed threshold.

[0077] Specifically, if the motor torque is greater than the preset motor torque threshold and the motor speed is less than the preset motor speed threshold, the working state of the motor is determined to be a stalled state; if the motor torque is equal to 0 or the motor speed is greater than or equal to the motor speed threshold, the working state of the motor is determined to be a non-stalled state.

[0078] In one possible implementation, the preset motor torque threshold is the motor rated torque. If the current motor torque is greater than the motor rated torque, the temperature of the motor and the motor controller will usually gradually rise. Setting the motor torque threshold to the motor rated torque can adopt a stall protection strategy before the temperature of the motor and the motor controller rises, thereby protecting the motor and the motor controller; the motor speed threshold can be the motor speed corresponding to the vehicle speed of 0.5km / h. This speed means that the vehicle has the intention to move but has no motion trajectory. In this case, if the motor torque is large, it proves that the current motor is in a stalled rotor condition. Of course, those skilled in the art can also set the motor torque threshold and the motor speed threshold to other values ​​according to actual conditions, and the embodiments of the present application are not limited to this.

[0079] In order to better record the current working state of the motor so as to facilitate the subsequent execution of the target stall protection strategy, in a possible implementation, a stall condition flag is set. When the working state of the motor is a stalled state, the stall condition flag A is the first working condition flag; when the working state of the motor is a non-stalled state, the stall condition flag A is the second working condition flag. In a possible implementation, when the working state of the motor is a stalled state, the stall condition flag A is 1; when the working state of the motor is a non-stalled state, the stall condition flag A is 0. Of course, those skilled in the art can also set the stall condition flag to other values ​​according to actual conditions, and the embodiments of the present application are not limited to this. For the convenience of description, hereinafter, a stall condition flag A of 1 is used to represent a stalled state, and a non-stalled state is represented by a stall condition flag A of 0.

[0080] In one possible implementation, when the motor torque is equal to 0 or the motor speed is greater than or equal to the motor speed threshold, due to device delay or other reasons, the stalled rotor condition flag A may be 1, but at this time the working state of the motor should be non-stalled rotor state, so when the motor torque is equal to 0 or the motor speed is greater than or equal to the motor speed threshold, it is determined whether the working state of the motor is a stalled rotor state. If the working state of the motor is displayed as a stalled rotor state, the working state of the motor is adjusted to a non-stalled rotor state, that is, the stalled rotor condition flag A is set to 0.

[0081] Step S103: If the working state of the motor is a stalled state, a first count value is calculated according to the temperature of the motor, and a second count value is calculated according to the temperature of the motor controller.

[0082] Specifically, if the working state of the motor is a stalled state, the motor counter is controlled to start counting and calculate the motor temperature rise, and the first count value is calculated based on the count value of the motor counter, the motor temperature and the motor temperature rise; at the same time, the motor controller counter is controlled to start counting and calculate the motor controller temperature rise, and the second count value is calculated based on the count value of the motor controller counter, the motor controller temperature and the motor controller temperature rise.

[0083] In a possible implementation, if the stalled rotor condition flag A is 1, the first count value is calculated according to formula (1), and the second count value is calculated according to formula (2).

[0084] In formula (1), the moment the stalled rotor condition flag A is set from 0 to 1, the motor counter starts timing. That is, the moment the stalled rotor condition flag A is set from 0 to 1 is t=0, and C motor_init T is the value of the motor counter from 0 to the current moment, motor_init is the motor temperature value at t=0, f α (Torq) is the motor temperature rise function corresponding to the motor speed and motor torque, where Torq represents the motor torque. α The value of (Torq) can be obtained by looking up the table based on the motor speed and motor torque. For example, Table 1 shows the motor speed (n), motor torque (T) and f α (Torq) value (indicated by y in the table), where y represents the temperature rise rate of the motor. It can be understood that Indicates the temperature rise of the motor. If the motor speed at time t1 is n1 and the motor torque is T1, then the f at time t1 is α The value of (Torq) is y 11 , the motor speed at time t2 is n1, and the motor torque is T2, then the f corresponding to time t2 α The value of (Torq) is y 12 , the current moment is t3, the motor speed is n1 at t3, and the motor torque is T3, then the f corresponding to t3 α The value of (Torq) is y 13 , then the current moment The value of It should be pointed out that C motor_init 、T motor_init and All are numerical values, without units. In addition, each time the motor controller wakes up from sleep mode, the value of C motor_init =0.

[0085] Table 1:

[0086] (2) In the formula, C mcu_init When the stall condition flag A is set from 0 to 1, the motor controller counter starts timing. At time t, the value of the motor controller counter is T mcu_init is the temperature value of the motor controller when the stall condition flag A is set from 0 to 1, f β (Torq) is the motor controller temperature rise function corresponding to the motor speed and motor torque, where Torq represents the motor torque. β The value of (Torq) can be obtained by looking up the table based on the motor speed and motor torque. For example, Table 2 shows the motor speed (n), motor torque (T) and f β (Torq) value (indicated by Y in the table), where Y represents the temperature rise rate of the motor controller. It can be understood that f β (Torq) represents the temperature rise of the motor controller. If the motor speed at time t1 is n1 and the motor torque is T1, then the f at time t1 is β The value of (Torq) is Y 11 , the motor speed at time t2 is n1, and the motor torque is T2, then the f corresponding to time t2 β The value of (Torq) is Y 12 , the current moment is t3, the motor speed is n1 at t3, and the motor torque is T3, then the f corresponding to t3 β The value of (Torq) is Y 13 , then the current moment The value of It should be pointed out that C mcu_init 、T mcu_init and All values ​​are numerical and do not include units.

[0087] Table 2:

[0088] Motor temperature rise function f α (Torq) and the motor controller temperature rise function f β (Torq) is obtained through offline testing. Specifically, the test environment temperature is set to the highest value of the working environment temperature in the technical requirements. The motor and motor controller stall temperature rise test benches are built separately. The motor and motor controller temperature sensors are pre-embedded and arranged as needed. After standing for a period of time, the initial temperature of the motor and motor controller is equal to the ambient temperature, and the test is started. The motor torque test points are taken with equal steps within the range of the motor rated torque Tn and the peak torque Tp. The peak current corresponding to the motor torque at the test point is injected into the motor and motor controller for temperature rise testing. Observe the temperature rise. When the motor temperature reaches the upper limit of the motor technical indicators or the motor controller temperature reaches the upper limit of the motor controller technical indicators, stop the test and record the temperature rise time.

[0089] Based on the above experiments, we can obtain scatter plots of the relationship between motor torque and motor temperature rise duration, and scatter plots of the relationship between motor torque and motor controller temperature rise duration. Furthermore, we can obtain scatter plots of the relationship between motor torque and motor temperature rise rate, and scatter plots of the relationship between motor torque and motor controller temperature rise rate. These scatter plots can be fitted to form motor temperature rise curves and motor controller temperature rise curves, respectively. It is worth noting that during this process, the motor speed remains unchanged. To obtain the relationship between motor torque and temperature rise duration at different motor speeds, the above experiments need to be repeated, which will not be detailed here.

[0090] The motor temperature rise curves corresponding to all motor speeds are integrated into a table, as shown in Table 1. Among them, T1, T2, and T3 represent different motor torques, n1, n2, and n3 represent different motor speeds, and y 11 This represents the motor temperature rise rate when the motor torque is T1 and the motor speed is n1. Additionally, if the required data in the table is not recorded during the experiment, it can be calculated based on the motor temperature rise curve. For example, if the motor temperature rise rate when the motor torque is T3 and the speed is n2 in Table 1 is not recorded during the experiment, the motor temperature rise function when the motor speed is n2 can be calculated based on the motor temperature rise curve when the motor speed is n2. Substituting the motor torque T3 into the motor temperature rise function, the motor temperature rise rate when the motor torque is T3 and the speed is n2 can be obtained.

[0091] Similarly, the temperature rise curves of the motor controller corresponding to all motor speeds are integrated into a table, as shown in Table 2. Among them, T1, T2, and T3 represent different motor torques, n1, n2, and n3 represent different motor speeds, and Y 11 This represents the temperature rise rate of the motor controller when the motor torque is T1 and the motor speed is n1. If the required data in the table is not recorded during the experiment, it can be calculated based on the motor controller temperature rise curve, which will not be described in detail here.

[0092] Calculating the first count value and the second count value according to the above method requires little computing power, has high executability, and has a wide range of applications.

[0093] Step S104: executing a target stall protection strategy according to the working state of the motor, the first count value, and the second count value.

[0094] Specifically, if the motor is in a stalled state, a determination is made as to whether the first count value or the second count value is greater than a first threshold value. If either the first count value or the second count value is greater than the first threshold value, a determination is made as to whether the first count value or the second count value is greater than a second threshold value. If either the first count value or the second count value is greater than the first threshold value and both are less than the second threshold value, a first-level stall protection strategy is implemented. If either the first count value or the second count value is greater than the second threshold value, a second-level stall protection strategy is implemented. If the first threshold value is less than the second threshold value, the first-level stall protection strategy has a lower protection level than the second-level stall protection strategy.

[0095] In one possible implementation, the limit value of the count value is measured through the above experiment. Specifically, the product of the temperature rise time when the temperature rise rate is the maximum and the maximum temperature rise rate is the limit value of the count value. In the embodiment of the present application, the first threshold (C1) is set to 0.6 times the limit value of the count value, and the second threshold (C2) is set to 0.8 times the limit value of the count value. Of course, those skilled in the art can also set the first and second thresholds to other values ​​according to actual circumstances, and the embodiment of the present application does not limit this.

[0096] It should be noted that the higher the protection level, the stricter the restrictions on the motor or motor controller, that is, the higher the protection level, the faster the motor and motor controller cool down, thereby avoiding burning out the motor or motor controller. In an embodiment of the present application, the first-level stall protection strategy is to reduce the carrier frequency of the motor controller. This protection strategy can reduce the temperature rise rate of the motor controller. At the same time, when the carrier frequency approaches the sensitive frequency area of ​​the human ear, the noise will serve as a reminder to the driver. The second-level stall protection strategy is to reduce the carrier frequency of the motor controller, and the limit value of the motor torque is limited to a first limit value. In an embodiment of the present application, the first limit value is the rated torque of the motor. The rated torque is the torque that the motor and motor controller can work for a long time, which can avoid further temperature rise. At the same time, since the current torque of the motor is limited to below the rated torque, the first count value and the second count value will no longer increase. Of course, those skilled in the art can also set the first limit value to other values ​​according to actual conditions, and the embodiment of the present application does not limit this.

[0097] In an embodiment of the present application, if any one of the first count value and the second count value is greater than the first threshold and both are less than the second threshold, the first-level stall protection strategy is executed. For the convenience of explanation, the first count value and the second count value are collectively referred to as C below, C1 is the first threshold, C2 is the second threshold, and C3 is the third threshold. C3<C1<C2, C>C1 indicates that any one of the first count value and the second count value is greater than the first threshold, C is less than C2 indicates that both the first count value and the second count value are less than the second threshold, and so on, C3<C<C1 indicates that any one of the first count value and the second count value is greater than the third threshold and both the first count value and the second count value are less than the first threshold, and C>C2 indicates that any one of the first count value and the second count value is greater than the second threshold.

[0098] In addition, in order to characterize the current stall protection state of the motor, a stall protection state bit B is set. When the stall protection state bit B is the first state bit, it indicates that the stall protection strategy currently executed by the motor is a first-level stall protection strategy. When the stall protection state bit B is the second state bit, it indicates that the stall protection strategy currently executed by the motor is a second-level stall protection strategy. When the stall protection state bit B is the third state bit, it indicates that the stall protection strategy currently executed by the motor is a third-level stall protection strategy. When the stall protection state bit B is the fourth state bit, it indicates that the motor currently exits the execution of the stall protection strategy. In the embodiment of the present application, the first state bit is 1, the second state bit is 2, the third state bit is 3, and the fourth state bit is 0. Of course, those skilled in the art can also set the state bit to other values ​​according to actual needs, and the embodiment of the present application does not limit this. For ease of description, hereinafter the first state bit is 1, the second state bit is 2, the third state bit is 3, and the fourth state bit is 0.

[0099] When the stall condition flag bit A is 1 and C1<C<C2, it means that the stall condition has lasted for a period of time and has a slight impact on the safety of the motor or motor controller. In this case, the first-level stall protection strategy is executed, and the stall protection status bit B is set to 1; if the stall condition flag bit A is 1 and C>C2, it means that the current condition is still stalled and has a serious impact on the safety of the motor or motor controller. In this case, the second-level stall protection strategy is executed, and the stall protection status bit B is set to 2.

[0100] Furthermore, if the motor is in a non-stalled state and either the first count value or the second count value is greater than the third threshold value and less than the first threshold value, the third-level stall protection strategy is executed. If the motor is in a non-stalled state and both the first count value and the second count value are less than or equal to the third threshold value, the stall protection strategy is exited. If the third threshold value is less than the first threshold value, the third-level stall protection strategy has a lower protection level than the first-level stall protection strategy.

[0101] In the embodiment of the present application, the third threshold is set to 0. Of course, those skilled in the art can also set the third threshold to other values ​​according to actual needs, and the embodiment of the present application does not limit this.

[0102] When the stalled rotor condition flag A is 0 and C3<C<C1, the first count value (C motor ) and the second count value (C mcu ) is calculated according to formula (3) and formula (4),

[0103] Where C motor_init and C mcu_init The counter value corresponding to the moment when the stall condition flag A is set from 1 to 0; f α (Tp) and f β (Tp) is the temperature rise function f α (Torq) and f β (Torq) assigns the two constants after the peak torque Tp, so f α (Tp) and f β The integral of (Tp) increases with time, C motor_init and C mcu_init As time goes by, it decreases. But if C motor_init and C mcu_init If the number decreases to a negative value, it may cause confusion in the count value and lose its reference value. Therefore, when C motor_init or C mcu_init When it is less than or equal to 0, assign C motor_init or C mcu_init Equal to 0.

[0104] The three-level stall protection strategy is to set the carrier frequency of the motor controller to the normal carrier frequency and limit the motor torque to the second limit value. In order to ensure that the motor torque increases smoothly and does not affect the safety of the motor and the motor controller when executing the three-level stall protection strategy, in the embodiment of the present application, the second limit value is calculated by formula (5):

[0105] T γ =T n +(1-C / C2)*(T p -T n ) (5)

[0106] Where, T γ is the second limit, T nis the rated torque of the motor, Tp is the peak torque of the motor, C is the current first count value or second count value, and C2 is the second threshold. Since the first count value and the second count value decrease in the process of executing the three-level stall protection strategy, and the other values ​​remain unchanged, the second limit T γ In the process of executing the three-level stall protection strategy, the second limit T γ The rated torque T of the motor n It recovers linearly and increases to the peak torque Tp.

[0107] If the stall condition flag bit A is 0 and C3<C<C1, it means that the working state of the motor is non-stalled, but the current temperature of the motor and motor controller is still high, so the three-level protection strategy is executed, and the stall protection status bit B is set to 3; if the stall condition flag bit A is 0 and C≤C3, it means that the temperature sensor on the motor or motor controller can already represent the temperature of the motor or motor sensor. At this time, the stall protection strategy is exited, and the stall protection status bit B is set to 0. At this time, the limit value of the motor torque is the peak torque Tp, and the carrier frequency of the motor controller is the normal carrier frequency.

[0108] In one possible implementation, if the jam condition flag bit A is 0, C3<C<C1, and the currently executed jam protection strategy is the second-level jam protection strategy (i.e., the jam protection status bit B is 2), then the third-level jam protection strategy is executed, and the jam protection status bit B is set to 3; if the jam condition flag bit A is 0, C3<C<C1, and the currently executed jam protection strategy is the first-level jam protection strategy or the third-level jam protection strategy (i.e., the jam protection status bit B is 1 or 3), then the execution of the jam protection strategy is exited, and the jam protection status bit B is set to 0.

[0109] In addition, in actual applications, when the stall condition flag bit A is 0 and the stall protection status bit B is 0, the motor may be in a non-stalled state, but C3 < C < C1. At this time, the motor is not in a stall condition, and the safety of the motor and the motor controller is not affected. Therefore, the stall protection strategy is exited and the stall protection status bit B is set to 0.

[0110] Corresponding to the above embodiments, the present application also provides a motor stall protection device.

[0111] Referring to Figure 2, a schematic diagram of the structure of a motor stall protection device provided in an embodiment of the present application is shown. As shown in Figure 2, the motor stall protection device may include: an acquisition module 201, a working state determination module 202, a calculation module 203, and an execution module 204. These components communicate via one or more buses. Those skilled in the art will understand that the structure of the control device shown in the figure does not constitute a limitation on the embodiments of the present invention. It can be a bus structure or a star structure, and can also include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0112] The acquisition module 201 is used to acquire the current motor temperature, motor speed, motor torque and motor controller temperature.

[0113] The working state determining module 202 is configured to determine the working state of the motor according to the motor torque and the motor speed, where the working state includes a stalled state and a non-stalled state.

[0114] The calculation module 203 is configured to calculate a first count value according to the motor temperature and a second count value according to the motor controller temperature if the working state of the motor is a stalled state.

[0115] The execution module 204 is configured to execute a target stall protection strategy according to the working state of the motor, the first count value, and the second count value.

[0116] For ease of understanding, the data playback processing method provided in the embodiment of the present application is described in detail below in conjunction with a specific implementation method.

[0117] Referring to Figure 3, there is shown a flow chart of another motor stall protection method provided by an embodiment of the present application. As shown in Figure 3, the method mainly includes the following steps.

[0118] Step S301: Acquire the current motor temperature, motor speed, motor torque and motor controller temperature.

[0119] Step S302: Determine whether the motor torque is greater than the motor torque threshold and the motor speed is less than the motor speed threshold. If so, execute step S303; if not, execute step S301.

[0120] Step S303: the stalled rotor condition flag A=1, and the first value and the second value are incremented.

[0121] Step S304: Determine whether the first count value is greater than the first threshold or the second count value is greater than the first threshold. If so, execute step S305; if not, execute step S301.

[0122] Step S305: Execute the first-level stall protection strategy.

[0123] Step S306: Determine whether the first count value is greater than the second threshold or the second count value is greater than the second threshold. If so, execute step S307; if not, execute step S301.

[0124] Step S307: Execute the secondary stall protection strategy.

[0125] Step S308: Determine whether the motor torque = 0 or the motor speed ≥ the motor speed threshold. If so, execute step S309; ​​if not, execute step S301.

[0126] Step S309: Determine whether the working state of the motor is a stalled state. If so, execute step S310; if not, execute step S301.

[0127] Step S310: the working state of the motor is adjusted to a non-locked state, and the first count value and the second count value are decreased.

[0128] Step S311: determine whether the first count value is greater than the third threshold or the second count value is greater than the third threshold. If so, execute step S313; if not, execute step S312.

[0129] Step S312: Exit execution of the stall protection strategy.

[0130] Step S313: Determine whether the currently executed stall protection strategy is a level one stall protection strategy or a level three stall protection strategy. If yes, execute step S315; if not, execute step S314.

[0131] Step S314: Execute the third-level stall protection strategy.

[0132] Step S315: Exit the execution of the stall protection strategy.

[0133] Step S316 : Determine whether the motor torque is 0 or the motor speed is greater than the motor speed threshold. If so, execute step S310 ; if not, execute step S302 .

[0134] For the specific contents involved in the embodiments of the present application, please refer to the description in the embodiments shown in Figures 1 and 2 above. For the sake of brevity, they will not be repeated here.

[0135] Corresponding to the above embodiment, the present application also provides a controller.

[0136] Referring to Figure 4, a schematic diagram of the structure of a controller provided in an embodiment of the present application is shown. The controller 400 may include: a processor 401, a memory 402, and a communication unit 403. These components communicate via one or more buses. Those skilled in the art will appreciate that the structure of the electronic device shown in the figure does not constitute a limitation on the embodiments of the present invention. It may be a bus structure or a star structure, and may include more or fewer components than shown, or combine certain components, or arrange the components differently.

[0137] The communication unit 403 is configured to establish a communication channel so that the electronic device can communicate with other devices and receive user data sent by other devices or send user data to other devices.

[0138] The processor 401 is the control center of the electronic device. It uses various interfaces and lines to connect various parts of the entire electronic device. It runs or executes software programs, instructions, and / or modules stored in the memory 402, and calls data stored in the memory to perform various functions of the electronic device and / or process data. The processor can be composed of an integrated circuit (IC), for example, it can be composed of a single packaged IC, or it can be composed of multiple packaged ICs with the same or different functions. For example, the processor 401 can only include a central processing unit (CPU). In an embodiment of the present invention, the CPU can be a single computing core or multiple computing cores.

[0139] The memory 402 is used to store the execution instructions of the processor 401. The memory 402 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0140] When the execution instructions in the memory 402 are executed by the processor 401 , the electronic device 400 is enabled to execute part or all of the steps in the embodiment shown in FIG. 1 .

[0141] In a specific implementation, the present invention further provides a computer storage medium, wherein the computer storage medium may store a program that, when executed, may include some or all of the steps of each embodiment of the simulation scenario generation method provided by the present invention. The storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

[0142] In the embodiments of the present application, "at least one" refers to one or more, and "more" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0143] Those skilled in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented using a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0144] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0145] In the several embodiments provided in this application, if any function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of this application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program code.

[0146] In this specification, reference can be made to the same or similar parts between the various embodiments. In particular, for the device embodiment and the terminal embodiment, since they are basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the description in the method embodiment.

Claims

1. A motor stall protection method, characterized in that: include: Get the current motor temperature, motor speed, motor torque and motor controller temperature; Determining a working state of the motor according to the motor torque and the motor speed, wherein the working state includes a stalled state and a non-stalled state; If the working state of the motor is a stalled state, a first count value is calculated according to the temperature of the motor, and a second count value is calculated according to the temperature of the motor controller; A target stall protection strategy is executed according to the working state of the motor, the first count value, and the second count value.

2. The method according to claim 1, characterized in that The step of determining the working state of the motor according to the motor torque and the motor speed includes: If the motor torque is greater than a preset motor torque threshold and the motor speed is less than a preset motor speed threshold, determining that the working state of the motor is a stalled state; If the motor torque is equal to 0 or the motor speed is greater than or equal to the motor speed threshold, it is determined that the working state of the motor is a non-stall state.

3. The method according to claim 2, characterized in that If the motor torque is equal to 0 or the motor speed is greater than or equal to the motor speed threshold, determining that the working state of the motor is a non-blocked state includes: If the motor torque is equal to 0 or the motor speed is greater than or equal to the motor speed threshold, determining whether the working state of the motor is a stalled state; If the working state of the motor is a stalled state, the working state of the motor is adjusted to a non-stalled state.

4. The method according to claim 1, characterized in that: If the working state of the motor is a stalled state, calculating a first count value according to the motor temperature includes: If the working state of the motor is a stalled state, the motor counter is controlled to start counting and calculate the motor temperature rise; The first count value is calculated according to the count value of the motor counter, the motor temperature, and the motor temperature rise.

5. The method according to claim 1, characterized in that: If the working state of the motor is a stalled state, calculating a second count value according to the temperature of the motor controller includes: If the working state of the motor is a stalled state, the motor controller counter is controlled to start counting and calculate the temperature rise of the motor controller; The second count value is calculated according to the count value of the motor controller counter, the motor controller temperature, and the motor controller temperature rise.

6. The method according to claim 1, characterized in that The step of executing a target stall protection strategy according to the working state of the motor, the count value of the motor counter and the count value of the motor controller counter includes: If the working state of the motor is a stalled state, executing a target stall protection strategy according to the first count value and / or the second count value; If the working state of the motor is a non-blocked state, the first count value and / or the second count value are used to Value determines whether to exit the stall protection strategy.

7. The method according to claim 6, characterized in that If the working state of the motor is a stalled state, executing a target stall protection strategy according to the first count value and / or the second count value includes: If the working state of the motor is a stalled state, and the first count value and / or the second count value is greater than a first threshold value, a first-level stall protection strategy is executed; If the working state of the motor is a stalled state, and the first count value and / or the second count value is greater than a second threshold value, a secondary stall protection strategy is executed; Among them, the first threshold is smaller than the second threshold, and the protection level of the first-level stall protection strategy is lower than that of the second-level stall protection strategy.

8. The method according to claim 7, characterized in that If the working state of the motor is a non-blocked rotor state, determining whether to exit the execution of the blocked rotor protection strategy according to the first count value and / or the second count value includes: If the working state of the motor is a non-stall state, and the first count value and / or the second count value is greater than a third threshold value, a third-level stall protection strategy is executed; If the working state of the motor is a non-stall state, and the first count value and / or the second count value is less than or equal to a third threshold value, then exiting the execution of the stall protection strategy; Among them, the third threshold is smaller than the first threshold, and the protection level of the third-level stall protection strategy is lower than that of the first-level stall protection strategy.

9. The method according to claim 8, characterized in that If the working state of the motor is a non-stall state, and the first count value and / or the second count value is greater than a third threshold, a three-level stall protection strategy is executed, including: If the working state of the motor is a non-stall state, the first count value and / or the second count value is greater than a third threshold value, and the currently executed stall protection strategy is the second-level stall protection strategy, then the third-level stall protection strategy is executed; If the working state of the motor is a non-stall state, the first count value and / or the second count value is greater than a third threshold, and the currently executed stall protection strategy is the first-level stall protection strategy or the third-level stall protection strategy, then the stall protection strategy is exited.

10. The method according to claim 8, characterized in that The first-level stall protection strategy includes: reducing the carrier frequency of the motor controller; The secondary stall protection strategy includes: reducing the carrier frequency of the motor controller and limiting the limit value of the motor torque to a first limit value; The three-level stall protection strategy includes: setting the carrier frequency of the motor controller to a normal carrier frequency, and limiting the limit value of the motor torque to a second limit value; The first limit value is less than or equal to the second limit value.

11. The method according to claim 10, characterized in that The first limit value is the rated torque; The second limit value increases gradually during the execution of the three-level stall protection strategy.

12. A motor stall protection device, characterized in that: include: An acquisition module is used to obtain the current motor temperature, motor speed, motor torque and motor controller temperature; A working state determination module, used for determining the working state of the motor according to the motor torque and the motor speed, wherein the working state includes a stalled state and a non-stalled state; A calculation module, configured to calculate a first count value according to the motor temperature and a second count value according to the motor controller temperature if the working state of the motor is a stalled state; An execution module is used to execute a target stall protection strategy according to the working state of the motor, the first count value and the second count value.

13. A controller, characterized in that: include: processor; Memory; And a computer program, wherein the computer program is stored in the memory, and the computer program includes instructions, and when the instructions are executed by the processor, the electronic device executes the method according to any one of claims 1 to 11.

14. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method according to any one of claims 1 to 11.

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