Motor controller protection method and device and controller

Abstract

The invention discloses a motor controller protection method and device and a controller, and the method comprises the steps: determining the working state of a motor controller, the working state comprises first indication data, second indication data or third indication data, the first indication data is used for indicating the electric frequency of the motor controller, and the second indication data is used for indicating the electric frequency of the motor controller; the second indication data is used for indicating the switching frequency of the power module, and the third indication data is used for indicating the target temperature of the power module; according to the working state, the working capacity range of the motor controller is determined, and the working capacity range is used for indicating the numerical range of the target torque which the motor can reach; and adjusting the working capability of the motor controller to meet the working capability range, wherein the working capability is used for indicating the target torque which the motor can reach. Therefore, the working capability range corresponds to the working state of the motor controller, so that the motor controller can still maintain reliable operation in the dynamic change process of the working state, and the motor controller is prevented from losing efficacy in the change process of the working state.

Description

Technical Field

[0001] This application relates to the field of electric motors, and in particular to a method, device and controller for protecting an electric motor controller. Background Technology

[0002] Currently, with the continuous advancement of electronic technology, electric drive systems are increasingly being applied in more practical scenarios to achieve the conversion between mechanical energy and electrical energy. As a component of the electric drive system, the motor controller converts direct current (DC) to alternating current (AC) to drive the motor. For example, in new energy vehicles equipped with a motor controller, the controller can convert the DC power from the energy storage battery into AC power to propel the vehicle forward.

[0003] In practical applications, to ensure that the junction temperature of the motor controller remains within its normal operating range, the motor controller can be cooled by coolant in the cooling system, thereby improving the reliability of the motor controller. The junction temperature is the actual operating temperature of the motor controller. However, when the cooling system experiences malfunctions such as coolant leakage or insufficient coolant replenishment, the motor controller may fail due to excessively high junction temperature. Summary of the Invention

[0004] This application provides a method, apparatus, and controller for protecting a motor controller, ensuring the reliability of the motor controller during dynamic changes in its operating state. Furthermore, this application also provides a corresponding computer-readable storage medium and computer program product.

[0005] In a first aspect, embodiments of this application provide a motor controller protection method, comprising: determining the operating state of the motor controller, the operating state including first indication data, second indication data, or third indication data, wherein the first indication data is used to indicate the electrical frequency of the motor controller, the second indication data is used to indicate the switching frequency of the power module of the motor controller, and the third indication data is used to indicate the target temperature of the power module; determining the operating capability range of the motor controller according to the operating state, the operating capability range indicating the numerical range of the target torque that the motor can achieve, the motor being controlled by the motor controller; and adjusting the operating capability of the motor controller to meet the operating capability range, the operating capability indicating the target torque that the motor can achieve.

[0006] In one possible implementation, before determining the operating state of the motor controller, the method further includes: acquiring coolant indication data, the coolant indication data being used to indicate the flow rate of the coolant, the coolant being used to cool the motor controller; determining the operating state of the motor controller includes: determining the operating state of the motor controller when the coolant indication data meets an abnormal condition.

[0007] In one possible implementation, the coolant indication data includes the temperature rise rate of the power module, and the coolant indication data meets an abnormal condition, including: the temperature rise rate is greater than a rate threshold.

[0008] In one possible implementation, the coolant indication data includes a dry-run flag of the water pump controller to which the coolant belongs, and the coolant indication data meets abnormal conditions, including: the value of the dry-run flag is a target value.

[0009] In one possible implementation, the method further includes: determining real-time torque indication data of the motor and the operating mode of the motor controller, the operating mode including electric mode or generator mode; and determining the rate threshold based on the first indication data, the real-time torque indication data, and the operating mode.

[0010] In one possible implementation, the operating state includes the first indication data and the second indication data. Determining the operating capacity range of the motor controller based on the operating state includes: determining a first operating capacity of the motor controller, wherein the first operating capacity is a positive number, and the first operating capacity is the maximum value of the motor controller's operating capacity under the condition that the first condition includes the coolant indication data meeting the abnormal condition, the motor controller being in electric mode, the motor controller's temperature being below a temperature threshold, and the motor controller being in the operating state; determining a second operating capacity of the motor controller, wherein the second operating capacity is a negative number, and the second operating capacity is the minimum value of the motor controller's operating capacity under the condition that the second condition includes the coolant indication data meeting the abnormal condition, the motor controller being in generator mode, the motor controller's temperature being below the temperature threshold, and the motor controller being in the operating state; and determining the operating capacity range, wherein the upper limit of the operating capacity range is the first operating capacity, and the lower limit of the operating capacity range is the second operating capacity.

[0011] In one possible implementation, the operating state includes third indication data. Determining the operating capacity range of the motor controller based on the operating state includes: determining the maximum value of the operating capacity of the motor controller in electric mode and the minimum value of the operating capacity of the motor controller in generator mode, wherein the maximum value is a positive number and the minimum value is a negative number; determining the weight value corresponding to the third indication data; and determining the operating capacity range based on the maximum value, the minimum value, and the weight value, wherein the upper limit of the operating capacity range is the product of the maximum value and the weight value, and the lower limit of the operating capacity range is the product of the minimum value and the weight value.

[0012] In one possible implementation, determining the third indication data includes: determining fourth indication data, the fourth indication data being used to indicate the initial temperature of the power module; acquiring the temperature rise rate and temperature delay of the power module, the temperature delay being the delay for determining the fourth indication data; and correcting the fourth indication data according to the temperature rise rate and the temperature delay to obtain the third indication data.

[0013] Secondly, embodiments of this application provide a motor controller protection device, comprising: a determining module, the determining module being configured to determine the operating state of the motor controller, the operating state including first indication data, second indication data, or third indication data, wherein the first indication data is used to indicate the electrical frequency of the motor controller, the second indication data is used to indicate the switching frequency of the power module of the motor controller, and the third indication data is used to indicate the target temperature of the power module; the determining module is further configured to determine the operating capability range of the motor controller based on the operating state, the operating capability range being used to indicate the numerical range of the target torque that the motor can achieve, the motor being controlled by the motor controller; and an adjusting module, the adjusting module being configured to adjust the operating capability of the motor controller to meet the operating capability range, the operating capability being used to indicate the target torque that the motor can achieve.

[0014] In one possible implementation, the device further includes: an acquisition module, configured to acquire coolant indication data before acquiring the operating status of the motor controller, the coolant indication data indicating the flow rate of the coolant, the coolant being used to cool the motor controller; and a determination module, specifically configured to: acquire the operating status of the motor controller when the coolant indication data meets an abnormal condition.

[0015] In one possible implementation, the coolant indication data includes the temperature rise rate of the power module, and the coolant indication data meets an abnormal condition, including: the temperature rise rate is greater than a rate threshold.

[0016] In one possible implementation, the coolant indication data includes a dry-run flag of the water pump controller to which the coolant belongs, and the coolant indication data meets abnormal conditions, including: the value of the dry-run flag is a target value.

[0017] In one possible implementation, the determining module is further configured to determine the real-time torque indication data of the motor and the operating mode of the motor controller, the operating mode including electric mode or generator mode; and to determine the rate threshold based on the first indication data, the real-time torque indication data and the operating mode.

[0018] In one possible implementation, the operating state includes the first indication data and the second indication data. The determining module is specifically configured to: determine a first operating capability of the motor controller, wherein the first operating capability is a positive number, and the first operating capability is the maximum value of the operating capability of the motor controller under the condition that the first condition includes the coolant indication data meeting the abnormal condition, the motor controller being in electric mode, the temperature of the motor controller being lower than the temperature threshold, and the motor controller being in the operating state; determine a second operating capability of the motor controller, wherein the second operating capability is a negative number, and the second operating capability is the minimum value of the operating capability of the motor controller under the condition that the second condition includes the coolant indication data meeting the abnormal condition, the motor controller being in power generation mode, the temperature of the motor controller being lower than the temperature threshold, and the motor controller being in the operating state; and determine a range of operating capabilities, wherein the upper limit of the range of operating capabilities is the first operating capability, and the lower limit of the range of operating capabilities is the second operating capability.

[0019] In one possible implementation, the operating state includes third indication data. The determining module is specifically configured to: determine the maximum value of the operating capacity of the motor controller in electric mode and the minimum value of the operating capacity of the motor controller in generator mode, wherein the maximum value is a positive number and the minimum value is a negative number; determine the weight value corresponding to the third indication data; and determine the operating capacity range based on the maximum value, the minimum value, and the weight value, wherein the upper limit of the operating capacity range is the product of the maximum value and the weight value, and the lower limit of the operating capacity range is the product of the minimum value and the weight value.

[0020] In one possible implementation, the determining module is specifically configured to: determine fourth indication data, the fourth indication data being used to indicate the initial temperature of the power module; acquire the temperature rise rate and temperature delay of the power module, the temperature delay being the delay for determining the fourth indication data; and correct the fourth indication data according to the temperature rise rate and the temperature delay to obtain third indication data.

[0021] Thirdly, embodiments of this application also provide a controller for executing the methods described in the first aspect and any one of the embodiments of the first aspect.

[0022] Fourthly, embodiments of this application also provide a computer-readable storage medium for storing a computer program for performing the methods described in the first aspect and any one of the embodiments of the first aspect.

[0023] Fifthly, embodiments of this application also provide a computer program product including instructions that, when run on a computing device, cause the computing device to perform the methods described in the first aspect and any one of the embodiments of the first aspect.

[0024] In the above implementation of this application embodiment, the operating state of the motor controller is determined. The operating state includes first indication data, second indication data, or third indication data. The first indication data indicates the electrical frequency of the motor controller, the second indication data indicates the switching frequency of the power module of the motor controller, and the third indication data indicates the target temperature of the power module. Based on the operating state, the operating capability range of the motor controller is determined. The operating capability range indicates the numerical range of the target torque that the motor can achieve, and the motor is controlled by the motor controller. The operating capability of the motor controller is adjusted to meet the operating capability range, where the operating capability indicates the target torque that the motor can achieve. Thus, by obtaining the operating state of the motor controller and determining the corresponding operating capability range based on that operating state, the operating capability of the motor controller can be limited based on the operating capability range to reduce the heat generated by the motor controller, prevent the junction temperature from exceeding the normal operating range, and ensure the reliability of the motor controller. Furthermore, since the operating capability range corresponds to the operating state of the motor controller, the motor controller can still maintain reliable operation during dynamic changes in its operating state, preventing the junction temperature from exceeding the normal operating range during changes in the operating state. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0026] Figure 1 This is a flowchart illustrating a motor controller protection method according to an embodiment of this application;

[0027] Figure 2a This is a table illustrating the correspondence between electric driving frequency and torque and speed threshold in one embodiment of the present application.

[0028] Figure 2b This is a table illustrating the correspondence between power generation frequency, torque, and rate threshold in one power generation mode according to an embodiment of this application.

[0029] Figure 3a This is a table illustrating the correspondence between the maximum working state and the maximum working capacity in one electric mode according to an embodiment of this application.

[0030] Figure 3b This is a table illustrating the correspondence between the minimum working state and working capacity under one power generation mode in an embodiment of this application.

[0031] Figure 4 This is a table illustrating the correspondence between a target temperature and a weight value in an embodiment of this application;

[0032] Figure 5a This is a data diagram illustrating a motor controller in an embodiment of this application when a cooling system malfunctions.

[0033] Figure 5b This is a data diagram illustrating a motor controller in another embodiment of this application when a cooling system malfunctions.

[0034] Figure 6 This is a schematic diagram of a motor controller protection process in an embodiment of this application;

[0035] Figure 7 This is a schematic diagram of the structure of a motor controller protection device according to an embodiment of this application. Detailed Implementation

[0036] The following description, in conjunction with the accompanying drawings, illustrates various non-limiting embodiments of this application. Obviously, the described embodiments are only a portion, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0037] See Figure 1 , Figure 1 A flowchart illustrating a motor controller protection method according to an embodiment of this application is shown. This method can be executed by a vehicle, a controller configured on the vehicle, or other controllers. The following description uses the example of a controller executing the motor controller protection method. Figure 1 As shown, the method may specifically include the following steps.

[0038] S101: The controller acquires the coolant indication data, which is used to indicate the coolant flow rate. The coolant is used to cool the motor controller.

[0039] S102: The controller determines whether the coolant indication data meets the abnormal conditions.

[0040] In practical applications, the motor controller can be cooled by the coolant in the cooling system to improve its reliability. Specifically, under the control of the water pump controller, the coolant flows in the cooling system loop, effectively reducing the junction temperature of the motor controller by absorbing the heat generated by it. However, when the cooling system experiences malfunctions such as coolant leakage or insufficient coolant replenishment, the heat generated by the motor controller cannot be carried away by the coolant, potentially leading to controller failure due to excessively high junction temperature.

[0041] Therefore, optionally, the controller can acquire coolant indication data, which indicates the coolant flow rate, and thus the controller can execute the motor controller protection method when the aforementioned possible faults occur in the cooling system. It should be noted that the coolant flow rate can be the amount of coolant flowing through the cooling system loop per unit time; for example, the coolant flow rate can be the volume of coolant passing through per minute. Alternatively, the coolant flow rate can also be the total amount of coolant in the cooling system loop; for example, the coolant flow rate can be the total coolant volume.

[0042] Based on the acquired coolant indication data, the controller can determine whether the coolant indication data meets abnormal conditions, and if the coolant indication data meets abnormal conditions, continue to execute step S103. This embodiment provides the following implementation examples of how the controller determines whether the coolant indication data meets abnormal conditions based on different coolant indication data.

[0043] In the first implementation example, the coolant indication data can be the dry-run flag bit of the water pump controller. The water pump controller controls the operation of the water pump to drive the coolant to circulate in the cooling system loop, thereby removing the heat generated by the motor controller. When the coolant flow rate in the cooling system is lower than the flow rate threshold, the water pump will experience a dry-run fault. When the water pump controller detects that the water pump is dry-running, it sets the value of the dry-run flag bit to a target value. The target value can be 1, 0, or any other value, without limitation. Furthermore, the coolant indication data meeting the abnormal condition can be that the dry-run flag bit is set to the target value. When the controller determines that the dry-run flag bit is set to the target value, the controller can continue to execute step S103.

[0044] In practice, the pump controller continuously monitors the pump. When a dry-running fault occurs, the pump controller sends a dry-running flag signal to the controller. The dry-running flag signal can be an analog signal. To avoid the jitter that may occur when generating the analog signal, causing the controller to make an error in determining the dry-running flag, the controller can use a debounce module to eliminate the influence of analog signal jitter on the determination of the dry-running flag.

[0045] In the second implementation example, the coolant indication data can be the temperature rise rate of the power module of the motor controller. Specifically, the controller can acquire the temperature of the power module's substrate multiple times. The substrate can be a direct-bonded copper (DBC) ceramic substrate or other substrates, without limitation. The controller can determine the temperature rise rate of the power module based on the temperature rise value within a target time period; that is, the temperature rise rate is the quotient of the temperature rise value and the duration of the target time period. When the coolant flow rate in the cooling system is lower than the flow rate threshold, the heat generated by the motor controller cannot be carried away by the coolant, resulting in a higher temperature rise rate of the power module of the motor controller. Based on this, the coolant indication data can meet the abnormal condition if the temperature rise rate of the power module is greater than the rate threshold. When the controller determines that the temperature rise rate is greater than the rate threshold, the controller can continue to execute step S103.

[0046] Furthermore, when the coolant flow rate in the cooling system is below the flow rate threshold, the motor controller may have different speed thresholds depending on its operating state. Preferably, the controller can determine the real-time torque indication data of the motor, the operating mode of the motor controller, and a first indication data, wherein the motor is controlled by the motor controller, the operating mode of the motor controller can be electric mode or generator mode, and the first indication data is used to indicate the electrical frequency of the motor controller. Furthermore, the controller can determine the speed threshold based on the first indication data, the real-time torque indication data, and the operating mode.

[0047] It is worth noting that the real-time torque indication data of the motor can be the motor's real-time torque or other indication data, such as the value of the motor's real-time current; there is no limitation on this. The primary indication data can be the electrical frequency of the motor controller, or other indication data, such as the electrical cycle of the motor controller, the motor's speed, etc.; there is no limitation on this. Furthermore, when the motor controller operates in motor mode, it controls the motor to convert electrical energy into mechanical energy; when the motor controller operates in generator mode, it controls the motor to convert mechanical energy into electrical energy.

[0048] It should be noted that the correspondence between the motor controller's operating state and the speed threshold can be pre-configured in the controller by technicians. In practical applications, technicians can test this in an experimental environment to improve the accuracy of the controller in determining whether the coolant level readings meet abnormal conditions.

[0049] For example, the explanation will focus on the controller determining the rate threshold based on the motor controller's electrical frequency, the motor's real-time torque, and the motor's operating mode. Under conditions where the coolant flow rate is 0 liters per minute and the motor controller's junction temperature is within its normal operating range, a technician can measure the rate of temperature rise of the power module at different electrical frequencies and different real-time torques when the motor controller is in motor mode. Figure 2a Table 1 shows the temperature rise rate of the power module at different electrical frequencies and different real-time torques when the motor controller is in generator mode, as can be measured by technicians. Figure 2bTable 2 shows the measurements, where the electrical frequency is in Hertz (Hz), the real-time torque is in Newton-meters (Nm), and the temperature rise rate is in degrees Celsius per second (°C / s). The measured temperature rise rate is the rate threshold used by the controller to determine whether the coolant readings meet the abnormal conditions. Specifically, when the motor controller is in motor mode, if the temperature rise rate determined by the controller is greater than the corresponding temperature rise rates for the electrical frequency and real-time torque in Table 1, the controller determines that the coolant readings meet the abnormal conditions. When the motor controller is in generator mode, if the temperature rise rate determined by the controller is greater than the corresponding temperature rise rates for the electrical frequency and real-time torque in Table 2, the controller determines that the coolant readings meet the abnormal conditions. Furthermore, since Tables 1 and 2 obtained by technicians have discrete correspondences, in practical applications, the correspondence between the unmeasured electrical frequency and real-time torque and the rate threshold can be obtained through linear calculations from either Table 1 or Table 2. For example, if there is no rate threshold in Table 1 corresponding to an electrical frequency of 10Hz and a real-time torque of 30Nm, the controller can use the rate thresholds corresponding to an electrical frequency of 10Hz and a real-time torque of 20Nm and the rate thresholds corresponding to an electrical frequency of 10Hz and a real-time torque of 40Nm to perform linear calculations to obtain the above rate thresholds.

[0050] It should be noted that technicians can obtain a relatively accurate junction temperature of the motor controller by measuring the temperature of a special power module configured in the motor controller using thermal imaging equipment. This special power module is a black module coated with a developer. Additionally, Figure 2a and Figure 2b The rate threshold in the data can be the average of the rate threshold measured multiple times by a technician.

[0051] In the third implementation example, the controller can combine the information from the first and second implementation examples to determine whether the coolant indication data meets the abnormal conditions. In the first implementation example, there is usually a significant detection delay between the water pump running dry and the water pump controller issuing the dry run flag signal; for example, the detection delay may be no less than 10 seconds. The anti-jitter module may also experience a significant anti-jitter delay in processing the analog signal of the dry run flag; for example, the detection delay may be no less than 1 second. However, in the second implementation example, the controller's method of determining whether the power module's temperature rise rate exceeds the rate threshold has better real-time performance. Based on this, the controller can determine whether the temperature rise rate exceeds the rate threshold before determining the dry run flag.

[0052] The different implementation examples described above are merely illustrative. In practical applications, the controller can also determine whether the coolant indication data meets abnormal conditions based on other coolant indication data, without limitation. For example, the controller can determine whether the coolant indication data meets abnormal conditions based on the flow meter readings in the cooling system loop, or the controller can compare the temperatures between multiple temperature measurement points in the cooling system loop to determine whether the coolant indication data meets abnormal conditions. However, compared to the implementation examples provided in this embodiment, the above implementation methods increase the complexity and cost of the cooling system. That is, additionally configuring flow meters or multiple temperature measurement points in the cooling system presents problems such as configuration difficulties, increased complexity of the cooling system, and increased cost of the cooling system, and is not a preferred implementation method.

[0053] S103: The controller determines the operating status of the motor controller. The operating status includes first indication data, second indication data, or third indication data. The first indication data is used to indicate the electrical frequency of the motor controller, the second indication data is used to indicate the switching frequency of the power module of the motor controller, and the third indication data is used to indicate the target temperature of the power module.

[0054] S104: Based on the working status, the controller determines the working capacity range of the motor controller. The working capacity range is used to indicate the numerical range of the target torque that the motor can achieve. The motor is controlled by the motor controller.

[0055] The controller can determine the operating state of the motor controller and, based on this state, determine the corresponding operating capacity range of the motor controller. Thus, even as the operating state of the motor controller dynamically changes, because the operating capacity range corresponds to the operating state, the motor controller can still maintain normal and reliable operation, effectively preventing the junction temperature of the motor controller from exceeding the normal operating range after the operating state changes. The operating state of the motor controller can be a first indication data, a second indication data, or a third indication data. The first indication data indicates the electrical frequency of the motor controller, the second indication data indicates the switching frequency of the power module, and the third indication data indicates the target temperature of the power module. Furthermore, the operating capacity range indicates the numerical range of the target torque that the motor can achieve, and the motor is controlled by the motor controller.

[0056] Optionally, before the controller determines the operating state of the motor controller, the controller may determine whether the coolant indication data meets the abnormal conditions, and if the coolant indication data meets the abnormal conditions, the controller determines the operating state of the motor controller.

[0057] It is worth noting that the first indicated data can be the electrical frequency of the motor controller, or other indicated data, such as the electrical cycle of the motor controller, the motor speed, etc., without limitation. The second indicated data can be the switching frequency of the power module, or other indicated data, such as the switching cycle of the power module, without limitation. The third indicated data can be the target temperature of the power module, or other indicated data, such as the target scale of the temperature measuring device of the power module, without limitation. The operating capacity range can be the numerical range of the target torque that the motor can achieve, or other indicated data, such as the numerical range of the target current that the motor can achieve, without limitation.

[0058] In this embodiment, the following implementation examples are provided for different controllers to determine the working capacity range of the motor controller according to different working states.

[0059] In the first implementation example, the operating state can be a first indication data and a second indication data. The controller can determine the operating capacity range of the motor controller based on the determined first and second indication data, thereby limiting the motor controller from entering limp-home mode. To prevent the junction temperature of the motor controller from exceeding the normal operating range, the controller can determine the upper and lower limits of the motor controller's operating capacity under certain conditions, thus obtaining the operating capacity range. Specifically, when the motor controller is in electric mode, the operating capacity value is positive, and the higher the operating capacity value, the more heat the motor controller generates. Therefore, the upper limit of the operating capacity range is the maximum value of the motor controller's operating capacity under the first condition, where the first condition includes the motor controller being in electric mode, the coolant indication data meeting abnormal conditions, the junction temperature of the motor controller being below a temperature threshold, and the motor controller being in a determined operating state. Similarly, when the motor controller is in generator mode, the operating capacity value is negative, and the lower the operating capacity value, i.e., the higher the absolute value of the operating capacity, the more heat the motor controller generates. Therefore, the lower limit of the operating capacity range is the minimum operating capacity of the motor controller under the condition that the second condition is met, wherein the second condition includes the motor controller being in power generation mode, the coolant indication data meeting the abnormal condition, the junction temperature of the motor controller being lower than the temperature threshold, and the motor controller being in a determined operating state.

[0060] It should be noted that the correspondence between the conditions met by the motor controller and the maximum or minimum operating capacity can be pre-configured in the controller by technicians. In practical applications, technicians can conduct tests in an experimental environment to ensure that the junction temperature of the motor controller does not exceed the normal operating range in the event of a cooling system failure.

[0061] For example, the explanation will focus on the controller determining its operating capacity range based on the electrical frequency of the motor controller and the switching frequency of the power module. Under conditions where the coolant flow rate is 0 liters per minute and the junction temperature of the motor controller is within its normal operating range, a technician can measure the maximum operating capacity of the motor controller in motor mode at different electrical frequencies and different rates of temperature rise. Figure 3a Table 3 shows the minimum operating capacity of the motor controller in generator mode at different electrical frequencies and different rates of temperature rise, which technicians can measure. Figure 3b Table 4 shows the units for electrical frequency and switching frequency, and the unit for operating capacity, Newton-meters (Nm). Furthermore, based on the determined electrical and switching frequencies and the correspondence shown in Table 3, the controller can obtain the maximum operating capacity of the motor controller when the first condition is met, i.e., the upper limit of the operating capacity range. Similarly, based on the determined electrical and switching frequencies and the correspondence shown in Table 4, the controller can obtain the minimum operating capacity of the motor controller when the second condition is met, i.e., the lower limit of the operating capacity range. Additionally, since the correspondences in Tables 3 and 4 obtained by technicians are discrete, in practical applications, the correspondence between unmeasured electrical and switching frequencies and the maximum operating capacity can be obtained through linear calculations using Table 3, and the correspondence between unmeasured electrical and switching frequencies and the minimum operating capacity can be obtained through linear calculations using Table 4. For example, if there is no maximum value for the working capacity corresponding to an electrical frequency of 10Hz and a switching frequency of 2.5k in Table 3, the controller can use the maximum value for the working capacity corresponding to an electrical frequency of 10Hz and a switching frequency of 2k and the maximum value for the working capacity corresponding to an electrical frequency of 10Hz and a switching frequency of 3k to perform linear calculations to obtain the maximum value for the aforementioned working capacity.

[0062] It should be noted that technicians can obtain a relatively accurate junction temperature of the motor controller by measuring the temperature of a special power module configured in the motor controller using thermal imaging equipment. This special power module is a black module coated with a developer. Additionally, Figure 3a and Figure 3b The maximum or minimum value of the work capacity can be the average of the work capacity measured multiple times by the technician.

[0063] In the second implementation example, the operating state can be a third indication data. The controller can determine the operating capacity range of the motor controller based on the determined third indication data, thereby limiting the motor controller's operating capacity. To prevent the junction temperature of the motor controller from exceeding the normal operating range, the controller can determine the upper and lower limits of the operating capacity of the motor controller's power module at different temperature levels, thus obtaining the operating capacity range. Specifically, when the motor controller is in electric mode, the operating capacity value is positive, and the higher the operating capacity value, the more heat the motor controller generates. Therefore, the controller can determine the maximum value of the motor controller's operating capacity in electric mode, and then limit the operating capacity according to the weight value corresponding to the third indication data; that is, the upper limit of the operating capacity range is the product of the maximum value of the operating capacity and the weight value. Similarly, when the motor controller is in generator mode, the operating capacity value is negative, and the lower the operating capacity value, that is, the higher the absolute value of the operating capacity, the more heat the motor controller generates. Therefore, the controller can determine the minimum value of the motor controller's working capacity in the power generation mode, and then limit the working capacity according to the weight value corresponding to the third indication data. That is, the lower limit of the working capacity range is the product of the minimum value of the working capacity and the weight value.

[0064] It should be noted that the correspondence between the third indication data and the weight values ​​can be pre-configured in the controller by technicians. In practical applications, technicians can test this in an experimental environment to ensure that the junction temperature of the motor controller does not exceed the normal operating range.

[0065] For example, the third indication data may be the target temperature of the power module, and the correspondence between the target temperature and the weight value is as follows: Figure 4 Table 5 shows the target temperature in degrees Celsius (°C) and the weight values ​​in percentages (%). For example, when the target temperature is 95°C, the upper limit of the working capacity range is half of the maximum value of the working capacity. Furthermore, since Table 5 contains discrete correspondences obtained from technician measurements, in practical applications, the correspondence between unmeasured target temperatures and weight values ​​can be obtained through linear calculations from Table 5.

[0066] Furthermore, the third indication data determined by the controller can be obtained by correcting the fourth indication data. Since there is a delay in the temperature of the power module determined by the controller—that is, there is a time difference between the actual temperature of the power module and the temperature determined by the controller—failure to correct the acquired temperature of the power module may result in the controller determining a temperature far lower than the actual temperature of the power module at the current time, thus affecting the weight value in the determination of the operating range. Based on this, the process of the controller determining the third indication data can be as follows: the controller first determines the fourth indication data, which indicates the initial temperature of the power module. The controller also acquires the temperature rise rate and temperature delay of the power module, where the temperature delay is the delay in determining the fourth indication data. The controller can then correct the fourth indication data based on the temperature rise rate and temperature delay to obtain the third indication data. For example, if the third indication data is the target temperature of the power module and the fourth indication data is the initial temperature of the power module, then the target temperature can be the initial temperature plus the product of the temperature rise rate and the temperature delay.

[0067] In the third implementation example, the controller can determine the working capacity range by combining the first and second implementation examples described above. Specifically, the controller can obtain a first working capacity range based on the first and second indication data, where the upper limit of the first working capacity range is the first working capacity and the lower limit is the second working capacity, based on the relevant description in the first implementation example. The controller can also obtain a second working capacity range based on the third indication data, where the upper limit of the second working capacity range is the third working capacity and the lower limit is the fourth working capacity. Furthermore, the controller can take the smaller value between the first and third working capacities as the upper limit of the working capacity range and the larger value between the second and fourth working capacities as the lower limit of the working capacity range.

[0068] It should be noted that the different implementation examples mentioned above are only illustrative examples. In actual applications, the controller can also determine the range of working capabilities based on other indication data, and there are no limitations on this.

[0069] S105: The controller adjusts the working capacity of the motor controller to meet the working capacity range. The working capacity is used to indicate the target torque that the motor can achieve.

[0070] Based on the operating capacity range determined by the controller, the controller can adjust the operating capacity of the motor controller to ensure that the operating capacity meets the range. The operating capacity range indicates the target torque that the motor can achieve. It should be noted that the operating capacity range can be the target torque that the motor can achieve, or other indicated data, such as the target current that the motor can achieve; there is no limitation on this. Furthermore, the motor controller's operating capacity may meet the operating capacity range before adjustment. Therefore, the controller can maintain the motor controller's operating capacity, or it can adjust the motor controller's operating capacity to the maximum or minimum value of the operating capacity range; there is no limitation on this.

[0071] In this way, the controller limits the working capacity of the motor controller based on its operating range to reduce the heat generated by the motor controller, prevent the junction temperature from exceeding the normal operating range, and ensure the reliability of the motor controller.

[0072] For example, such as Figure 5a The diagram shows data from the motor controller when a cooling system malfunction occurs. Figure 5a The curves include the target temperature of the power module versus time, the real-time torque of the motor versus time, and the operating capacity of the motor controller versus time. At 0.2 seconds, the controller determines that the temperature rise rate exceeds the rate threshold. Therefore, the controller restricts the motor controller from entering limp mode, i.e., adjusting the operating capacity of the motor controller to 100 Nm. Ultimately, the target temperature of the power module stabilizes at around 95℃, preventing the motor controller from failing due to junction temperature exceeding the normal operating range. Figure 5b The diagram shown is another data representation of the motor controller when a cooling system malfunction occurs. Figure 5b The data includes curves showing the target temperature of the power module changing over time, the real-time torque of the motor changing over time, and the operating capacity of the motor controller changing over time. At 0.8 seconds, the controller limits the operating capacity of the motor controller based on the target temperature of the power module, adjusting it to 100 Nm. It should be noted that during this process, the operating capacity of the motor controller fluctuates. This is because changes in operating capacity cause fluctuations in the target temperature, which in turn cause fluctuations in the operating capacity and real-time torque. Finally, over time, the operating capacity of the motor controller converges to 100 Nm, and the target temperature stabilizes at 96°C. At 12 seconds, the controller detects a dry-running flag and prevents the motor controller from entering limp-mode. Ultimately, the target temperature of the power module stabilizes at around 95°C, preventing the motor controller from failing due to junction temperature exceeding its normal operating range.

[0073] In this embodiment, the controller can continuously determine the operating state of the motor controller using the steps described in steps S103 to S105 above, and obtain the corresponding operating capacity range of the motor controller when it is in that operating state. This allows the controller to limit its operating capacity based on the operating capacity range, thereby reducing the heat generated by the motor controller, preventing the junction temperature from exceeding the normal operating range, and ensuring the reliability of the motor controller. Additionally, the controller can continuously determine whether the coolant indicator data meets abnormal conditions using the steps described in steps S101 to S105 above, and determine the operating state of the motor controller if the coolant indicator data meets abnormal conditions.

[0074] Figure 6 This is an example of a motor controller protection process provided in an embodiment of this application. This process can be executed by the controller.

[0075] First, the controller can determine if the cooling system is experiencing faults such as coolant leakage or insufficient coolant replenishment. One example is as follows: The controller determines the motor controller's electrical frequency, real-time motor torque, and operating mode, and uses the correspondence indicated in Tables 1 and 2 to determine a rate threshold. Based on the substrate temperature, the controller determines the temperature rise rate. Then, the controller checks if the temperature rise rate exceeds the rate threshold; if so, the cooling system may be experiencing faults such as coolant leakage or insufficient coolant replenishment. Another example is as follows: The controller determines the dry-run flag of the water pump controller and uses an anti-jitter module to de-jitter the signal of the dry-run flag. Then, the controller checks if the dry-run flag is at the target value; if so, the cooling system may be experiencing faults such as coolant leakage or insufficient coolant replenishment.

[0076] Secondly, the controller can provide limp-limit protection or temperature-based derating protection for the motor controller. An example of limp-limit protection is as follows: When the controller determines that the cooling system has a fault such as coolant leakage or insufficient coolant replenishment, the controller can determine the electrical frequency of the motor controller and the switching frequency of the power module. Then, based on the correspondence indicated in Tables 3 and 4, the controller determines a first operating capacity and a second operating capacity. The first operating capacity is the motor controller's operating capacity in electric mode and is a positive value, while the second operating capacity is the motor controller's operating capacity in generator mode and is a negative value. An example of temperature-based derating protection is as follows: The controller determines the temperature of the power module's substrate and corrects this temperature according to the temperature rise rate and temperature delay to obtain a target temperature. Then, based on the target temperature and the correspondence indicated in Table 5, the controller limits the maximum and minimum values ​​of the motor controller's operating capacity to obtain a third operating capacity and a fourth operating capacity. The third operating capacity is the motor controller's operating capacity in electric mode and is a positive value, while the fourth operating capacity is the motor controller's operating capacity in generator mode and is a negative value.

[0077] Finally, the controller takes the smaller value between the first and third working capabilities as the upper limit of the working capability range and the larger value between the second and fourth working capabilities as the lower limit of the working capability range, thus obtaining the working capability range. In this way, the controller adjusts the working capability of the motor controller to meet the working capability range.

[0078] Furthermore, this application also provides a motor controller protection device. (See also...) Figure 7 , Figure 7 This paper shows a schematic diagram of the structure of a motor controller protection device according to an embodiment of the present application. Figure 7 The motor controller protection device 700 shown includes:

[0079] A determining module 701 is used to determine the operating state of the motor controller. The operating state includes first indication data, second indication data, or third indication data. The first indication data indicates the electrical frequency of the motor controller, the second indication data indicates the switching frequency of the power module of the motor controller, and the third indication data indicates the target temperature of the power module. The determining module 701 is also used to determine the operating capability range of the motor controller based on the operating state. The operating capability range indicates the numerical range of the target torque that the motor can achieve. The motor is controlled by the motor controller. An adjusting module 702 is used to adjust the operating capability of the motor controller to meet the operating capability range. The operating capability indicates the target torque that the motor can achieve.

[0080] In one possible implementation, the device further includes: an acquisition module 703, which is configured to acquire coolant indication data before acquiring the operating status of the motor controller, the coolant indication data indicating the flow rate of the coolant, the coolant being used to cool the motor controller; and a determination module 701, specifically configured to: acquire the operating status of the motor controller when the coolant indication data meets an abnormal condition.

[0081] In one possible implementation, the coolant indication data includes the temperature rise rate of the power module, and the coolant indication data meets an abnormal condition, including: the temperature rise rate is greater than a rate threshold.

[0082] In one possible implementation, the coolant indication data includes a dry-run flag of the water pump controller to which the coolant belongs, and the coolant indication data meets abnormal conditions, including: the value of the dry-run flag is a target value.

[0083] In one possible implementation, the determining module 701 is further configured to determine the real-time torque indication data of the motor and the operating mode of the motor controller, the operating mode including electric mode or generator mode; and determine the rate threshold based on the first indication data, the real-time torque indication data and the operating mode.

[0084] In one possible implementation, the operating state includes the first indication data and the second indication data. The determining module 701 is specifically configured to: determine the first operating capability of the motor controller, wherein the value of the first operating capability is a positive number, and the first operating capability is the maximum value of the operating capability of the motor controller under the condition that the first condition includes the coolant indication data meeting the abnormal condition, the motor controller being in electric mode, the temperature of the motor controller being lower than the temperature threshold, and the motor controller being in the operating state; determine the second operating capability of the motor controller, wherein the value of the second operating capability is a negative number, and the second operating capability is the minimum value of the operating capability of the motor controller under the condition that the second condition includes the coolant indication data meeting the abnormal condition, the motor controller being in power generation mode, the temperature of the motor controller being lower than the temperature threshold, and the motor controller being in the operating state; and determine the operating capability range, wherein the upper limit of the operating capability range is the first operating capability, and the lower limit of the operating capability range is the second operating capability.

[0085] In one possible implementation, the operating state includes third indication data. The determining module 701 is specifically configured to: determine the maximum value of the operating capacity of the motor controller in electric mode and the minimum value of the operating capacity of the motor controller in generator mode, wherein the maximum value is a positive number and the minimum value is a negative number; determine the weight value corresponding to the third indication data; and determine the operating capacity range based on the maximum value, the minimum value, and the weight value, wherein the upper limit of the operating capacity range is the product of the maximum value and the weight value, and the lower limit of the operating capacity range is the product of the minimum value and the weight value.

[0086] In one possible implementation, the determining module 701 is specifically configured to: determine fourth indication data, the fourth indication data being used to indicate the initial temperature of the power module; acquire the temperature rise rate and temperature delay of the power module, the temperature delay being the delay for determining the fourth indication data; and correct the fourth indication data according to the temperature rise rate and the temperature delay to obtain third indication data.

[0087] It should be noted that the information interaction and execution process between the modules and units of the above-mentioned device are based on the same concept as the method embodiment in this application, and the resulting technical effects are the same as those in the method embodiment in this application. For details, please refer to the description in the method embodiment shown above in this application, and it will not be repeated here.

[0088] In addition, this application embodiment also provides a controller, which is used to execute the motor controller protection method described in the above method embodiment.

[0089] In addition, this application embodiment also provides a computer-readable storage medium for storing a computer program for executing the motor controller protection method described in the above method embodiment.

[0090] In addition, this application also provides a computer program product containing instructions that, when run on a computing device, causes the computing device to execute the motor controller protection method described in the above method embodiments.

[0091] In the embodiments of this application, the word "first" in names such as "first indication data" is only used for naming purposes and does not represent the first in order. This rule also applies to "second," "third," etc.

[0092] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that all or part of the steps in the methods of the above embodiments can be implemented by means of software plus a general-purpose hardware platform. Based on this understanding, the technical solution of this application can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as a read-only memory (ROM) / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, a server, or a network communication device such as a router) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0093] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the device embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. The device embodiments described above are merely illustrative. Modules described as separate components may or may not be physically separate, and components shown as modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0094] The above description is merely an exemplary implementation of this application and is not intended to limit the scope of protection of this application.

Claims

1. A method for protecting a motor controller, characterized in that, The method includes: The operating state of the motor controller is determined, and the operating state includes a first indication data, a second indication data, or a third indication data, wherein the first indication data is used to indicate the electrical frequency of the motor controller, the second indication data is used to indicate the switching frequency of the power module of the motor controller, and the third indication data is used to indicate the target temperature of the power module. Based on the operating state, the operating capacity range of the motor controller is determined. The operating capacity range indicates the numerical range of the target torque that the motor can achieve. The motor is controlled by the motor controller. The operating capacity of the motor controller is adjusted to meet the operating capacity range, wherein the operating capacity is used to indicate the target torque that the motor can achieve.

2. The method according to claim 1, characterized in that, Before obtaining the operating status of the motor controller, the method further includes: Acquire coolant indication data, which is used to indicate the flow rate of the coolant, and the coolant is used to cool the motor controller; Determining the operating state of the motor controller includes: When the coolant indicator data meets the abnormal conditions, the operating status of the motor controller is determined.

3. The method according to claim 2, characterized in that, The coolant indication data includes the temperature rise rate of the power module, and the coolant indication data meets abnormal conditions, including: The rate of temperature rise is greater than the rate threshold.

4. The method according to claim 2, characterized in that, The coolant indication data includes the dry-run flag of the water pump controller to which the coolant belongs. The coolant indication data meets abnormal conditions, including: The value of the dry-running flag is the target value.

5. The method according to claim 3, characterized in that, The method further includes: The real-time torque indication data of the motor and the operating mode of the motor controller are determined, the operating mode including electric mode or generator mode; The rate threshold is determined based on the first indication data, the real-time torque indication data, and the operating mode.

6. The method according to claim 2, characterized in that, The operating status includes the first indication data and the second indication data. Determining the operating capability range of the motor controller based on the operating status includes: The first working capacity of the motor controller is determined. The value of the first working capacity is a positive number. The first working capacity is the maximum value of the working capacity of the motor controller under the condition that the first condition is met. The first condition includes the coolant indication data meeting the abnormal condition, the motor controller being in electric mode, the temperature of the motor controller being lower than the temperature threshold, and the motor controller being in the working state. A second working capacity of the motor controller is determined. The value of the second working capacity is a negative number. The second working capacity is the minimum value of the working capacity of the motor controller under the condition that the second condition is met. The second condition includes the coolant indication data meeting the abnormal condition, the motor controller being in power generation mode, the temperature of the motor controller being lower than the temperature threshold, and the motor controller being in the working state. The range of work capabilities is determined, wherein the upper limit of the range of work capabilities is the first work capability, and the lower limit of the range of work capabilities is the second work capability.

7. The method according to claim 2, characterized in that, The operating status includes third indication data, and determining the operating capability range of the motor controller based on the operating status includes: Determine the maximum value of the working capacity of the motor controller in electric mode and the minimum value of the working capacity of the motor controller in generator mode, wherein the maximum value is a positive number and the minimum value is a negative number; Determine the weight value corresponding to the third indication data; The working capacity range is determined based on the maximum value, the minimum value, and the weight value. The upper limit of the working capacity range is the product of the maximum value and the weight value, and the lower limit of the working capacity range is the product of the minimum value and the weight value.

8. The method according to claim 7, characterized in that, The determination of the third indication data includes: A fourth indication data is determined, the fourth indication data being used to indicate the initial temperature of the power module; The temperature rise rate and temperature delay of the power module are obtained, wherein the temperature delay is the delay for determining the fourth indication data; The third indication data is obtained by correcting the fourth indication data based on the temperature rise rate and the temperature delay.

9. A motor controller protection device, characterized in that, The device includes: The determining module is used to determine the operating state of the motor controller. The operating state includes first indication data, second indication data, or third indication data. The first indication data indicates the electrical frequency of the motor controller, the second indication data indicates the switching frequency of the power module of the motor controller, and the third indication data indicates the target temperature of the power module. The determining module is also used to determine the operating capability range of the motor controller based on the operating state. The operating capability range indicates the numerical range of the target torque that the motor can achieve, and the motor is controlled by the motor controller. An adjustment module is provided to adjust the working capacity of the motor controller to meet the working capacity range, wherein the working capacity indicates the target torque that the motor can achieve.

10. A controller, characterized in that, The controller is used to perform the method according to any one of claims 1-8.

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