A method and system for over-temperature derating of a drive motor system

Abstract

The present invention discloses a method and system for over-temperature derating of a drive motor system, the method comprising: obtaining real-time temperature information of a drive motor; and then judging whether a first preset temperature is exceeded; if exceeded, starting a first counting instruction, and obtaining a countable accumulative time corresponding to a current current, and then based on a preset time interval and a current current, performing cumulative counting or cumulative subtraction on the countable accumulative time to obtain a cumulative time result or a cumulative subtraction time result; judging whether the cumulative time result or the cumulative subtraction time result satisfies a first logical relationship; if satisfied, generating a first end instruction to end counting.

Description

Technical Field

[0001] The present invention relates to the field of drive motors, and in particular to an over-temperature derating method and system for a drive motor system. Background Art

[0002] With the advancement of technology, the software and hardware of general drive motor systems have over-temperature protection functions. The over-temperature protection strategy of the drive motor system is generally IGBT over-temperature protection and motor over-temperature protection. There are three NTC (Negative Temperature Coefficient) temperature sensors in the IGBT module, and one or two NTC / PT1000 temperature sensors in the motor. The temperature is collected by the sensor, and the protection threshold is set by the software to achieve the purpose of over-temperature protection.

[0003] However, the temperature protection strategy in the prior art can limit the IGBT temperature and the motor temperature to a safe range when the driving conditions of the electric vehicle are not too severe, and will not cause over-temperature protection, demagnetization of the motor, and shorten the life of the motor. Summary of the invention

[0004] The purpose of the present invention is to provide a method and system for over-temperature derating of a drive motor system, so as to solve the temperature protection strategy in the prior art. When the driving conditions of an electric vehicle are not too severe, the IGBT temperature and the motor temperature can be limited to a safe range, and over-temperature protection will not cause demagnetization of the motor and affect the technical problem of the motor life.

[0005] In view of the above problems, the present invention provides a method and system for over-temperature derating of a drive motor system.

[0006] In a first aspect, the present invention provides a method for over-temperature derating of a drive motor system, the method being implemented by an over-temperature derating system for a drive motor system, wherein the method comprises: obtaining real-time temperature information of the drive motor; judging whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature, wherein the first preset temperature corresponds to a first operating current; if the real-time temperature exceeds the first preset temperature, starting a first counting instruction according to the real-time temperature information; obtaining a countable accumulative time corresponding to a current current according to the first counting instruction, wherein the countable accumulative time is the time required for the temperature of the drive motor to rise from the first preset temperature to a second preset temperature when the current current is running, and the second preset temperature corresponds to a second operating current; based on a preset time interval and the current current, performing cumulative counting or cumulative subtraction counting on the countable accumulative time to obtain a cumulative time result or a cumulative time result; judging whether the cumulative time result or the cumulative time result satisfies a first logical relationship; if the cumulative time result or the cumulative time result satisfies the first logical relationship, generating a first end instruction to end counting.

[0007] On the other hand, the present invention further provides a drive motor system overtemperature derating system for executing a drive motor system overtemperature derating method as described in the first aspect, wherein the system includes: a first obtaining unit, the first obtaining unit is used to obtain real-time temperature information of the drive motor; a first judgment unit, the first judgment unit is used to judge whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature, wherein the first preset temperature corresponds to a first operating current; a first starting unit, the first starting unit is used to start a first counting instruction according to the real-time temperature information if the real-time temperature exceeds the first preset temperature; a second obtaining unit, the second obtaining unit is used to obtain a count accumulative value corresponding to the current current according to the first counting instruction. The counting time is as follows: the counting accumulative time is the time required for the temperature of the drive motor to rise from the first preset temperature to the second preset temperature when the current is running, and the second preset temperature corresponds to the second operating current; a first counting unit, the first counting unit is used to add or subtract the counting accumulative time based on a preset time interval and the current current to obtain an accumulated time result or an accumulated time result; a second judgment unit, the second judgment unit is used to judge whether the accumulated time result or the accumulated time result satisfies a first logical relationship; a first generating unit, the first generating unit is used to generate a first end instruction to end the counting if the accumulated time result or the accumulated time result satisfies the first logical relationship.

[0008] In a third aspect, the present invention further provides an over-temperature derating system for a drive motor system, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method described in the first aspect when executing the program.

[0009] A fourth aspect is an electronic device, comprising a processor and a memory;

[0010] The processor is used to execute any one of the methods in the first aspect by calling.

[0011] In a fifth aspect, a computer program product comprises a computer program and / or instructions, which, when executed by a processor, implement the steps of any one of the methods described in the first aspect.

[0012] One or more technical solutions provided in the present invention have at least the following technical effects or advantages:

[0013] By obtaining the real-time temperature information of the driving motor, it is determined whether the temperature exceeds the first preset temperature. If so, the first counting instruction can be started, and the counting accumulative time corresponding to the current current can be obtained. Then, based on the preset time interval and the current current, the counting accumulative time can be accumulated or subtracted to obtain the accumulated time result or the accumulated time result. By determining whether the accumulated time result or the accumulated time result satisfies the first logical relationship, if so, a first end instruction can be generated to end the counting. The heat generated by the motor is characterized by the time integral of the phase current Q=I 2 t, through the actual calibration of the motor test bench for the sustainable operation time of different phase currents, the purpose of starting the derating protection before the motor temperature reaches the over-temperature protection threshold is achieved, so as to avoid the motor system reporting over-temperature protection and affecting the driving experience; at the same time, the technical effect of avoiding the motor temperature soaring and affecting the motor life is achieved.

[0014] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0016] Figure 1A schematic diagram of a process flow of an over-temperature derating method for a drive motor system according to the present invention;

[0017] Figure 2 It is a schematic diagram of a flow chart of adding or subtracting the counting accumulative time in a method for over-temperature derating of a drive motor system according to the present invention;

[0018] Figure 3 A schematic flow chart of an over-temperature protection derating strategy for a drive motor system in an over-temperature derating method for a drive motor system of the present invention;

[0019] Figure 4 A schematic diagram of a flow chart of determining whether the accumulated time result or the accumulated time result satisfies a first logical relationship in a method for over-temperature derating of a drive motor system according to the present invention;

[0020] Figure 5 A schematic diagram of the structure of an over-temperature derating system for a drive motor system according to the present invention;

[0021] Figure 6 It is a schematic diagram of the structure of an exemplary electronic device of the present invention.

[0022] Description of reference numerals:

[0023] A first obtaining unit 11 , a first judging unit 12 , a first starting unit 13 , a second obtaining unit 14 , a first counting unit 15 , a second judging unit 16 , a first generating unit 17 , a bus 300 , a receiver 301 , a processor 302 , a transmitter 303 , a memory 304 , and a bus interface 305 . DETAILED DESCRIPTION

[0024] The present invention provides a method and system for over-temperature derating of a drive motor system to solve the temperature protection strategy in the prior art. When the driving conditions of the electric vehicle are not too bad, the IGBT temperature and the motor temperature can be limited to a safe range, which will not cause over-temperature protection, demagnetization of the motor, and affect the technical problem of the motor life. The heat generated by the motor is characterized by the time integral of the phase current Q = I 2 t, through the actual calibration of the motor test bench for the sustainable operation time of different phase currents, the purpose of starting the derating protection before the motor temperature reaches the over-temperature protection threshold is achieved, so as to avoid the motor system reporting over-temperature protection and affecting the driving experience; at the same time, the technical effect of avoiding the motor temperature soaring and affecting the motor life is achieved.

[0025] The acquisition, storage, use, and processing of data in the technical solution of the present invention are in compliance with the relevant provisions of national laws and regulations.

[0026] Below, the technical solutions in the present invention will be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments of the present invention. It should be understood that the present invention is not limited to the example embodiments described herein. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. It should also be noted that, for the convenience of description, only the parts related to the present invention are shown in the accompanying drawings, rather than all of them.

[0027] The present invention provides a method for over-temperature derating of a drive motor system, and the method is applied to an over-temperature derating system of a drive motor system, wherein the method comprises: obtaining real-time temperature information of a drive motor; judging whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature, wherein the first preset temperature corresponds to a first working current; if the real-time temperature exceeds the first preset temperature, starting a first counting instruction according to the real-time temperature information; obtaining a countable accumulative time corresponding to a current current according to the first counting instruction, wherein the countable accumulative time is the time required for the temperature of the drive motor to rise from the first preset temperature to a second preset temperature when the current current is running, and the second preset temperature corresponds to a second working current; based on a preset time interval and the current current, performing cumulative counting or cumulative subtraction counting on the countable accumulative time to obtain a cumulative time result or a cumulative time result; judging whether the cumulative time result or the cumulative subtraction time result satisfies a first logical relationship; if the cumulative time result or the cumulative subtraction time result satisfies the first logical relationship, generating a first end instruction to end counting.

[0028] After introducing the basic principles of the present invention, various non-limiting implementation methods of the present invention will be specifically described below in conjunction with the accompanying drawings.

[0029] Embodiment 1

[0030] Please see attached Figure 1 The present invention provides a method for over-temperature derating of a drive motor system, wherein the method is applied to an over-temperature derating system of a drive motor system, and the method specifically comprises the following steps:

[0031] Step S100: obtaining real-time temperature information of the drive motor;

[0032] Specifically, with the advancement of technology, the software and hardware of general drive motor systems have over-temperature protection functions. The over-temperature protection strategy of the drive motor system is generally IGBT over-temperature protection and motor over-temperature protection. However, this temperature protection strategy can limit the IGBT temperature and motor temperature to a safe range when the driving conditions of electric vehicles are not too bad, and will not cause over-temperature protection. In order to avoid this problem, this application proposes a drive motor system over-temperature derating strategy, which uses the time integral of the phase current to characterize the accumulation of heat Q = I 2 t, the motor test bench is used to calibrate the continuous running time of different phase currents, so as to achieve the purpose of starting the derating protection before the motor temperature reaches the over-temperature protection threshold. First, it can avoid the motor system reporting over-temperature protection and affecting the driving experience; second, it can avoid the motor temperature soaring and affecting the motor life.

[0033] Specifically, the drive motor, that is, the motor drive system, can directly convert electrical energy into mechanical energy, which determines the performance indicators of the electric vehicle. The real-time temperature information is the temperature of the drive motor when it is working. As we all know, due to the long working time or large current passing through the motor during operation, the working temperature of the motor will be high, which seriously affects the normal operation of the motor. Therefore, by dynamically collecting the working temperature of the drive motor, the motor can be effectively protected by derating before over-temperature protection.

[0034] Step S200: determining whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature, wherein the first preset temperature corresponds to a first operating current;

[0035] Step S300: if the real-time temperature exceeds the first preset temperature, start a first counting instruction according to the real-time temperature information;

[0036] Furthermore, step S200 further includes:

[0037] Step S210: if the real-time temperature information is less than the first preset temperature, generating a first end instruction;

[0038] Step S220: according to the first end instruction, end the counting of the driving motor.

[0039] Specifically, after the real-time temperature information is known to be obtained, in order to conduct a safety assessment on it, it can be determined whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature, wherein the first preset temperature corresponds to a first working current, which is the working current passing through the drive motor when the drive motor is working, represented by I_1. When the current continues to run, the preset temperature of the drive motor is the first preset temperature, and 85°C is taken as an example for illustration.

[0040] By judging whether the real-time temperature corresponding to the real-time temperature information exceeds the first preset temperature, that is, judging whether the temperature of the drive motor is greater than 85°C in real time, if it is greater, starting the first counting instruction, which is to start I 2 T counts, specifically, using the time integral of the phase current to characterize the heat accumulation Q = I 2 t, the motor test bench is used to calibrate the continuous operation time of different phase currents, so as to achieve the purpose of starting the derating protection before the motor temperature reaches the over-temperature protection threshold. On the contrary, if the real-time temperature information is less than the first preset temperature, that is, if the drive motor temperature is <85°C, the output current can be no longer limited according to the first end instruction, so as to end the counting of the drive motor.

[0041] Step S400: Obtaining a countable accumulative time corresponding to the current current according to the first counting instruction, wherein the countable accumulative time is the time required for the temperature of the drive motor to rise from the first preset temperature to the second preset temperature when the current current is running, and the second preset temperature corresponds to the second operating current;

[0042] Specifically, when starting I 2 When T is counted, the counting accumulative time corresponding to the current current can be obtained, wherein the current current is represented by I_pre, and the counting accumulative time is represented by Tmax. Specifically, it can be expressed as the time required for the temperature of the drive motor to rise from the first preset temperature, i.e., 85°C, to the second preset temperature when the current current I_pre continues to run, wherein the second preset temperature is illustrated here using 140°C as an example, and the second working current is the working current passing through the drive motor when it is working, represented by I_2. It should be noted that it is necessary to ensure that the final temperature of the drive motor is less than 150°C. The specifications of the drive motor are different, so that the corresponding motor temperature alarm threshold is different. For example, assuming that the current is 400A and runs continuously for 10s, the motor temperature increases from 85°C to 140°C, then Tmax=10s.

[0043] Step S500: Based on a preset time interval and the current current, the countable accumulative time is accumulated or decreased to obtain an accumulated time result or an accumulated time result;

[0044] Further, such as Figure 2 As shown, step S500 includes:

[0045] Step S510: determining whether the current current is greater than the second working current;

[0046] Step S520: if the current current is greater than the second working current, the counting accumulative time is accumulated and counted;

[0047] Step S530: determining whether the current current is less than the first working current, and the sum of the time when the first counting instruction is started is 0;

[0048] Step S540: If the current current is less than the first working current, and the sum of the time when the first counting instruction is started is 0, the counting accumulative time is counted down.

[0049] Step S550: determining whether the current current is greater than the first operating current and less than the second operating current;

[0050] Step S560: If the current current is greater than the first working current and less than the second working current, the counting accumulative time is accumulated and counted.

[0051] Specifically, if Figure 3 As shown, when the counting accumulative time is counted up or down, further, it can be judged according to the numerical values ​​between the current current I_pre and I_1 and I_2, as follows:

[0052] First, first determine whether the current current I_pre is greater than the second working current I_2. If the current current I_pre is greater than the second working current I_2, it means that the current working current of the drive motor has exceeded the second working current I_2. Correspondingly, it can be inferred that before the motor temperature reaches the over-temperature protection threshold, the counting accumulative time needs to be accumulated, that is, Total=Total+2ms / Tmax, wherein the Total here can be characterized as the accumulated counting time, and Total=0 when the counting is started. The preset time interval is described here by taking 2ms as an example. The Tmax here can be characterized as the time required for the motor temperature to rise from 85°C to 140°C (calibrated amount) when the current current I_pre is continuously running;

[0053] Secondly, it can be determined whether the current current I_pre is less than the first working current I_1, and the time sum when the first counting instruction is started is 0. If the current current I_pre is less than the first working current I_1, and the time sum when the first counting instruction is started is 0, it means that the current working current of the drive motor has not reached the first working current I_1. Correspondingly, it can be inferred that before the motor temperature reaches the over-temperature protection threshold, the counting accumulative time needs to be counted down, that is, Total = Total-2ms / Tmax, where Total can be represented as the cumulative counting time, and Tmax here = Tmax_1. Because the current working current of the drive motor has not reached the first working current I_1, therefore, Tmax here can be represented as the continuous operation time of the current less than I_1 is Tmax_1 = 30min;

[0054] Third, finally determine whether the current current I_pre is greater than the first working current I_1 and less than the second working current I_2. If the current current is greater than the first working current and less than the second working current, that is, I_1≤current current I_pre≤I_2, it means that the current working current of the drive motor is between I_1 and I_2. Correspondingly, it can be inferred that before the motor temperature reaches the over-temperature protection threshold, the counting accumulative time needs to be accumulated, that is, Total=Total+2ms / Tmax, where Total can be represented as the accumulated counting time and Tmax=Tmax_2. When the current working current of the drive motor is between I_1 and I_2, until the subsequent continuous operation with the current I_2, the current continuous operation time when the temperature rises from 85°C to 140°C (calibrated quantity) is represented by Tmax_2.

[0055] By matching the above three different judgment methods, the corresponding cumulative time result or cumulative subtraction time result can be obtained, wherein the cumulative time result corresponds to the current current I_pre being greater than the second working current I_2, and I_1≤current current I_pre≤I_2. In these two judgment situations, the cumulative subtraction time result corresponds to the current current I_pre being less than the first working current I_1, and the sum of the time when the first counting instruction is started is 0.

[0056] Step S600: determining whether the accumulated time result or the accumulated time result satisfies a first logical relationship;

[0057] Step S700: If the accumulated time result or the accumulated time result satisfies the first logical relationship, a first end instruction is generated to end the counting.

[0058] Specifically, if Figure 3As shown, after obtaining the accumulated time result or the accumulated time result, it is necessary to determine whether the accumulated time result or the accumulated time result satisfies the first logical relationship, that is, whether Total is less than or equal to 0. If the accumulated time result or the accumulated time result satisfies the first logical relationship, that is, Total≤0, it means that it is no longer accumulated or subtracted and gradually tends to be stable, and a first end instruction can be generated to end the I of the drive motor. 2 T count is used to start the derating protection before the motor temperature reaches the over-temperature protection threshold.

[0059] Further, such as Figure 4 As shown, the step S600 of determining whether the accumulated time result or the accumulated time result satisfies the first logical relationship includes:

[0060] Step S610: if the accumulated time result does not satisfy the first logical relationship, obtaining a limited output current, wherein the limited output current is an output current limited when the second operating current is derated;

[0061] Step S620: Obtaining a corresponding maximum limiting torque of the motor controller according to the limited output current;

[0062] Step S630: determining whether the maximum torque limit of the motor controller is less than the torque command of the vehicle controller;

[0063] Step S640: if the maximum torque limit of the motor controller is less than the torque command of the vehicle controller, output the maximum torque limit of the motor controller;

[0064] Step S650: Controlling the driving motor according to the maximum torque limit of the motor controller.

[0065] Step S660: if the maximum torque limit of the motor controller is greater than the torque command of the vehicle controller, output the torque command of the vehicle controller;

[0066] Step S670: Control the drive motor according to the torque instruction of the vehicle controller.

[0067] Specifically, when determining whether the accumulated time result or the subtracted time result satisfies the first logical relationship, specifically, if the accumulated time result does not satisfy the first logical relationship, that is, Total is not less than or equal to 0, further, when Total ≥ 1.0, a limited output current can be obtained, characterized as I_output, where the limited output current I_output is the output current limited when the second operating current I_2 is derated, that is, I_output < I_2. Further, according to the limited output current I_output, the maximum limit torque of the motor controller can be obtained, and the maximum limit torque of the motor controller can be characterized as Torque_2. The motor controller is a core power electronic unit unique to new energy vehicles. By receiving the vehicle driving control instructions from the vehicle control unit, it controls the motor to output the specified torque and speed to drive the vehicle. It realizes the conversion of the DC electrical energy of the power battery into the required high-voltage alternating current and drives the motor body to output mechanical energy. The so-called torque means that mechanical components will produce a certain degree of torsional deformation under the action of torque, so torque is sometimes also called torsional moment. Torque is the basic load form of the drive shafts of various working machines and is closely related to factors such as the working ability, energy consumption, efficiency, operating life, and safety performance of power machinery. The measurement of torque is of great significance for determining and controlling the load of the drive shaft, the strength design of the working parts of the transmission system, and the selection of the capacity of the prime mover. In this application, the maximum limit torque of the motor controller is the maximum torque of the drive motor under the control of the electric vehicle motor controller at the limited output current.

[0068] More specifically, it is judged whether the maximum limit torque of the motor controller is less than the torque command of the vehicle control unit. The vehicle control unit is the core electronic control unit that realizes the vehicle control decision-making. Generally, only new energy vehicles are equipped with it, and traditional fuel vehicles do not require this device. By monitoring vehicle state (vehicle speed, temperature, etc.) information, after being judged and processed by the vehicle control unit, it sends vehicle operation state control instructions to the power system and the power battery system, and at the same time controls the working mode of the on-vehicle accessory power system. The structural composition of the vehicle control unit includes a housing, a hardware circuit, a bottom layer software, and an application layer software. The hardware circuit, the bottom layer software, and the application layer software are the key core technologies of the vehicle control unit. If the maximum limit torque Torque_2 of the motor controller is less than the torque command of the vehicle control unit, the maximum limit torque of the motor controller is output, and then the drive motor is controlled.

[0069] On the contrary, if the maximum torque limit Torque_2 of the motor controller is greater than the torque command of the vehicle controller, the torque command of the vehicle controller is output, and then the drive motor is controlled according to the torque command of the vehicle controller. It should be noted that when entering the derating protection, the maximum torque limit of the motor controller needs to be uploaded to the vehicle controller as a reference through a message. This prevents the motor system from reporting over-temperature protection, affecting the driving experience, and at the same time prevents the motor temperature from soaring, affecting the motor life.

[0070] Furthermore, the application also includes:

[0071] Step S810: Determine whether the accumulated time result or the accumulated time result satisfies a second logical relationship;

[0072] Step S820: if the accumulated time result or the accumulated time result satisfies the second logical relationship, output a first return instruction;

[0073] Step S830: According to the first return instruction, the countable accumulative time is counted up or down.

[0074] Specifically, when judging the accumulated time result or the accumulated time result, it is also possible to judge whether the accumulated time result or the accumulated time result satisfies a second logical relationship, wherein the second logical relationship can be characterized as whether the accumulated time result or the accumulated time result is greater than 0 and less than 1 at the same time, that is, 0<Total<1. If the accumulated time result or the accumulated time result satisfies the second logical relationship, the above-mentioned method of obtaining I according to the current current I_pre can be returned according to the first return instruction. 2 T can accumulate time Tmax, that is, re-obtain Tmax, and then continue to accumulate or subtract counting on this basis until exiting I 2 T count.

[0075] In summary, the over-temperature derating method for a drive motor system provided by the present invention has the following technical effects:

[0076] 1. By real-time judging whether the temperature of the drive motor Temp_Motor is greater than 85°C, if the temperature of the drive motor Temp_Motor>85°C, start I 2 T count, Total = 0; obtain I according to the current current I_pre 2 T can accumulate time Tmax; carry out I with an interval of 2ms 2T cumulative addition and subtraction counting; when Total ≥ 1.0, the output current is limited to I_output < I_2, and the maximum limit torque of the motor controller is Torque_2; if the torque command of the vehicle controller > Torque_2, output according to Torque_2, if the torque command of the vehicle controller < Torque_2, output according to the torque command of the vehicle controller; if Total ≤ 0, then exit I 2 T counting; if 0 < Total < 1, then return to continue cumulative addition and subtraction counting. The over-temperature derating strategy of the drive motor system proposed by the present invention, compared with the traditional over-temperature protection strategy, adds the time integral of the phase current to characterize heat accumulation, and together with the existing technology, implements double thermal protection for the motor system.

[0077] 2. If the current current I_pre > I_2, then perform cumulative counting, Total = Total + 2ms / Tmax; if the current current I_pre < I_1 and Total > 0, then perform subtraction counting, Tmax = Tmax_1, Total = Total - 2ms / Tmax; if Total ≤ 0, then end I 2 T counting; if I_1 ≤ the current current I_pre ≤ I_2, then perform cumulative calculation, Tmax = Tmax_2, Total = Total + 2ms / Tmax. The over-temperature derating strategy of the drive motor system proposed by the present invention can start derating protection before the motor temperature reaches the over-temperature protection threshold. One is to avoid the motor system reporting over-temperature protection and affecting the driving experience; the other is to avoid the motor temperature soaring and affecting the motor life.

[0078] Embodiment 2

[0079] Based on the same inventive concept as an over-temperature derating method of a drive motor system in the foregoing embodiment, the present invention also provides an over-temperature derating system for a drive motor system. Please refer to the attached Figure 5 , the system includes:

[0080] The first acquisition unit 11, the first acquisition unit 11 is used to acquire the real-time temperature information of the drive motor;

[0081] The first judgment unit 12, the first judgment unit 12 is used to judge whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature, wherein the first preset temperature corresponds to a first working current;

[0082] The first start unit 13, the first start unit 13 is used to start a first counting instruction according to the real-time temperature information if the real-time temperature exceeds the first preset temperature;

[0083] A second obtaining unit 14, the second obtaining unit 14 is used to obtain a countable accumulative time corresponding to the current current according to the first counting instruction, wherein the countable accumulative time is the time required for the temperature of the drive motor to rise from the first preset temperature to the second preset temperature when the current current is running, and the second preset temperature corresponds to a second operating current;

[0084] A first counting unit 15, the first counting unit 15 is used to accumulate or subtract the countable accumulative time based on a preset time interval and the current current to obtain an accumulated time result or a accumulated time result;

[0085] A second judgment unit 16, the second judgment unit 16 is used to judge whether the accumulated time result or the accumulated time result satisfies a first logical relationship;

[0086] The first generating unit 17 is used to generate a first end instruction to end counting if the accumulated time result or the accumulated time result satisfies the first logical relationship.

[0087] Furthermore, the system also includes:

[0088] a third judging unit, the third judging unit being used to judge whether the current current is greater than the second working current;

[0089] a second counting unit, the second counting unit being used for accumulating the counting accumulative time if the current current is greater than the second working current;

[0090] a fourth judgment unit, the fourth judgment unit being used to judge whether the current current is less than the first working current, and the sum of the time when the first counting instruction is started is 0;

[0091] A third counting unit, wherein the third counting unit is used to count down the accumulative counting time if the current current is less than the first working current and the sum of the times when the first counting instruction is started is 0.

[0092] Furthermore, the system also includes:

[0093] a fifth judging unit, configured to judge whether the current current is greater than the first operating current and less than the second operating current;

[0094] A fourth counting unit, wherein the fourth counting unit is used to accumulate and count the accumulative counting time if the current current is greater than the first working current and less than the second working current.

[0095] Furthermore, the system also includes:

[0096] a third obtaining unit, the third obtaining unit being used for obtaining a limited output current if the accumulated time result does not satisfy the first logical relationship, wherein the limited output current is an output current limited when the second operating current is derated;

[0097] A fourth obtaining unit, the fourth obtaining unit being used to obtain a corresponding maximum limiting torque of the motor controller according to the limited output current;

[0098] A sixth judgment unit, the sixth judgment unit is used to judge whether the maximum limit torque of the motor controller is less than the torque command of the vehicle controller;

[0099] A first output unit, the first output unit is used to output the maximum limit torque of the motor controller if the maximum limit torque of the motor controller is less than the torque command of the vehicle controller;

[0100] A first control unit is used to control the driving motor according to a maximum torque limit of the motor controller.

[0101] Furthermore, the system also includes:

[0102] A second output unit, the second output unit is used to output the torque command of the vehicle controller if the maximum limit torque of the motor controller is greater than the torque command of the vehicle controller;

[0103] A second control unit, wherein the second control unit is used to control the drive motor according to a torque instruction of the vehicle controller.

[0104] Furthermore, the system also includes:

[0105] a seventh judgment unit, the seventh judgment unit being used to judge whether the accumulated time result or the accumulated time result satisfies a second logical relationship;

[0106] a third output unit, the third output unit being configured to output a first return instruction if the accumulated time result or the accumulated time result satisfies the second logical relationship;

[0107] A fifth counting unit, wherein the fifth counting unit is used to perform cumulative counting or cumulative counting on the countable accumulative time according to the first return instruction.

[0108] Furthermore, the system also includes:

[0109] a second generating unit, the second generating unit being configured to generate a first end instruction if the real-time temperature information is less than the first preset temperature;

[0110] A first ending unit, wherein the first ending unit is used to end the counting of the driving motor according to the first ending instruction.

[0111] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. Figure 1 The over-temperature derating method and specific examples of a drive motor system in the first embodiment are also applicable to an over-temperature derating system of a drive motor system in the present embodiment. Through the above detailed description of the over-temperature derating method of a drive motor system, those skilled in the art can clearly know the over-temperature derating system of a drive motor system in the present embodiment, so for the sake of brevity of the specification, it will not be described in detail here. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description.

[0112] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0113] Exemplary Electronic Devices

[0114] Reference below Figure 6 The electronic device of the present invention will be described.

[0115] Figure 6 The figure shows a schematic structural diagram of an electronic device according to the present invention.

[0116] Based on the inventive concept of a method for over-temperature derating of a drive motor system in the aforementioned embodiment, the present invention also provides a system for over-temperature derating of a drive motor system, on which a computer program is stored, and when the program is executed by a processor, the steps of any method of the method for over-temperature derating of a drive motor system described above are implemented.

[0117] Among them, Figure 6In the embodiment of the present invention, a bus architecture (represented by bus 300) is shown, which may include any number of interconnected buses and bridges, and bus 300 links various circuits including one or more processors represented by processor 302 and memory represented by memory 304. Bus 300 may also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are not further described herein. Bus interface 305 provides an interface between bus 300 and receiver 301 and transmitter 303. Receiver 301 and transmitter 303 may be the same element, namely a transceiver, which provides a unit for communicating with various other devices over a transmission medium.

[0118] The processor 302 is responsible for managing the bus 300 and general processing, while the memory 304 may be used to store data used by the processor 302 when performing operations.

[0119] The present invention provides a method for over-temperature derating of a drive motor system, and the method is applied to an over-temperature derating system of a drive motor system, wherein the method comprises: obtaining real-time temperature information of a drive motor; judging whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature, wherein the first preset temperature corresponds to a first working current; if the real-time temperature exceeds the first preset temperature, starting a first counting instruction according to the real-time temperature information; obtaining a countable accumulative time corresponding to a current current according to the first counting instruction, wherein the countable accumulative time is the time required for the temperature of the drive motor to rise from the first preset temperature to a second preset temperature when the current current is running, and the second preset temperature corresponds to a second working current; based on a preset time interval and the current current, performing cumulative counting or cumulative subtraction counting on the countable accumulative time to obtain a cumulative time result or a cumulative time result; judging whether the cumulative time result or the cumulative subtraction time result satisfies a first logical relationship; if the cumulative time result or the cumulative subtraction time result satisfies the first logical relationship, generating a first end instruction to end counting. The temperature protection strategy in the prior art is solved. When the driving conditions of electric vehicles are not too bad, the IGBT temperature and the motor temperature can be limited to a safe range, which will not cause over-temperature protection, demagnetization of the motor, and affect the technical problems of the motor life. The heat generated by the motor is characterized by the time integral of the phase current Q = I 2 t, through the actual calibration of the motor test bench for the sustainable operation time of different phase currents, the purpose of starting the derating protection before the motor temperature reaches the over-temperature protection threshold is achieved, so as to avoid the motor system reporting over-temperature protection and affecting the driving experience; at the same time, the technical effect of avoiding the motor temperature soaring and affecting the motor life is achieved.

[0120] The present invention also provides an electronic device, which includes a processor and a memory;

[0121] The memory is used for storing;

[0122] The processor is used to execute any one of the methods in the above-mentioned embodiment 1 by calling.

[0123] The present invention also provides a computer program product, including a computer program and / or instructions, which, when executed by a processor, implement the steps of the method described in any one of the above-mentioned embodiments.

[0124] It should be understood by those skilled in the art that the embodiments of the present invention may be provided as methods, devices, or computer program products. Therefore, the present invention may adopt the form of a complete software embodiment, a complete hardware embodiment, or a combination of software and hardware embodiments. In addition, the present invention is in the form of a computer program product that can be implemented on one or more computer-usable storage media containing computer-usable program codes. The computer-usable storage medium includes, but is not limited to, various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), disk memories, compact disc read-only memories (CD-ROM), optical memories, etc.

[0125] The present invention is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A system that specifies the functions of a box or multiple boxes.

[0126] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction system, which is implemented in the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0127] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they understand the basic creative concepts.

[0128] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention belong to the scope of the present invention and its equivalent technologies, the present invention is also intended to include these changes and variations.

Claims

1. A method for over-temperature derating of a drive motor system, characterized in that: The method comprises: Obtain real-time temperature information of the drive motor; Determining whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature, wherein the first preset temperature corresponds to a first operating current; If the real-time temperature exceeds the first preset temperature, starting a first counting instruction according to the real-time temperature information; According to the first counting instruction, the counting accumulable time corresponding to the current current is obtained, wherein the counting accumulable time is the time required for the temperature of the drive motor to rise from the first preset temperature to the second preset temperature when the current current is running, and the second preset temperature corresponds to the second working current; Based on the preset time interval and the current current, the countable accumulative time is accumulated or decreased to obtain an accumulated time result or an accumulated time result; Determining whether the accumulated time result or the accumulated time result satisfies a first logical relationship; If the accumulated time result or the accumulated time result satisfies the first logical relationship, a first end instruction is generated to end the counting; The determining whether the accumulated time result or the accumulated time result satisfies a first logical relationship includes: If the accumulated time result does not satisfy the first logical relationship, a limited output current is obtained, wherein the limited output current is an output current limited when the second operating current is derated; According to the limited output current, obtaining a corresponding maximum limit torque of the motor controller; Determining whether the maximum torque limit of the motor controller is less than the torque command of the vehicle controller; If the maximum torque limit of the motor controller is less than the torque command of the vehicle controller, the maximum torque limit of the motor controller is output; The driving motor is controlled according to the maximum limiting torque of the motor controller.

2. The method according to claim 1, characterized in that The counting accumulative time is counted up or counted down, including: Determining whether the current current is greater than the second operating current; If the current current is greater than the second working current, the counting accumulative time is accumulated and counted; Determine whether the current current is less than the first working current, and the sum of the time when the first counting instruction is started is 0; If the current current is less than the first working current and the sum of the time when the first counting instruction is started is 0, the counting accumulative time is counted down.

3. The method according to claim 2, characterized in that The method further comprises: Determining whether the current current is greater than the first operating current and less than the second operating current; If the current current is greater than the first working current and less than the second working current, the counting accumulable time is counted cumulatively.

4. The method according to claim 1, characterized in that The determining whether the maximum torque limit of the motor controller is less than the torque command of the vehicle controller includes: If the maximum torque limit of the motor controller is greater than the torque command of the vehicle controller, outputting the torque command of the vehicle controller; The drive motor is controlled according to the torque instruction of the vehicle controller.

5. The method according to claim 1, characterized in that The method further comprises: Determining whether the accumulated time result or the accumulated time result satisfies a second logical relationship; If the accumulated time result or the accumulated time result satisfies the second logical relationship, output a first return instruction; According to the first return instruction, the countable accumulable time is counted up or down.

6. The method according to claim 1, characterized in that The determining whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature includes: If the real-time temperature information is less than the first preset temperature, generating a first end instruction; According to the first end instruction, the counting of the driving motor is ended.

7. A drive motor system overtemperature derating system, characterized in that: The system comprises: A first obtaining unit, wherein the first obtaining unit is used to obtain real-time temperature information of the driving motor; a first judging unit, configured to judge whether the real-time temperature corresponding to the real-time temperature information exceeds a first preset temperature, wherein the first preset temperature corresponds to a first operating current; a first starting unit, the first starting unit being used to start a first counting instruction according to the real-time temperature information if the real-time temperature exceeds the first preset temperature; a second obtaining unit, the second obtaining unit being used to obtain, according to the first counting instruction, a countable accumulative time corresponding to the current current, wherein the countable accumulative time is a time required for the temperature of the drive motor to rise from the first preset temperature to the second preset temperature when the current current is running, and the second preset temperature corresponds to a second operating current; A first counting unit, the first counting unit is used to accumulate or subtract the countable accumulative time based on a preset time interval and the current current to obtain an accumulated time result or a accumulated time result; A second judgment unit, the second judgment unit is used to judge whether the accumulated time result or the accumulated time result satisfies a first logical relationship; A first generating unit, the first generating unit is used for generating a first ending instruction to end counting if the accumulated time result or the accumulated time result satisfies the first logical relationship; The second judgment unit is further used for: If the accumulated time result does not satisfy the first logical relationship, a limited output current is obtained, wherein the limited output current is an output current limited when the second operating current is derated; According to the limited output current, obtaining a corresponding maximum limit torque of the motor controller; Determining whether the maximum torque limit of the motor controller is less than the torque command of the vehicle controller; If the maximum torque limit of the motor controller is less than the torque command of the vehicle controller, the maximum torque limit of the motor controller is output; The driving motor is controlled according to the maximum limiting torque of the motor controller.

8. An electronic device, characterized in that: including a processor and a memory; The memory is used for storing; The processor is used to execute the method according to any one of claims 1 to 6 by calling.

9. A computer program product comprising a computer program and / or instructions, characterized in that: When the computer program and / or the instructions are executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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