Vehicle motor control method and device, motor controller and vehicle
Through real -time acquisition of motor speed and torque, judge and adjust the maximum available torque under the motor conditions, solve the problem of thermal disorders of motor controller caused by insufficient judgments in the existing technology, improve the safety and reliability of the vehicle system sex.
Patent Information
- Application Number
- CN202411717212.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-01-28
AI Technical Summary
The existing vehicle motor control methods are not comprehensive enough to deal with blockages, resulting in the motor controller facing the risk of thermal failure and the safety of the vehicle system cannot be guaranteed.
Through real -time acquisition of the speed and torque of the motor, determine whether the motor meets the condition of the rotation or low -speed conditions, and adjust the maximum available torque of the motor according to different operating conditions (first working conditions, second work conditions, and third working conditions) The motor controller is too temperature.
A more accurate judgment of the motor conditions and the accurate adjustment of the maximum available torque can be effectively avoided, which effectively avoids the overload or damage of the motor controller, and improves the safety and reliability of the vehicle system.
Smart Images
Figure CN119369950A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of vehicle technology, and in particular to a control method and device for a vehicle motor, a motor controller and a vehicle. Background Art
[0002] With the development of the three-electric (battery, motor, and electronic control system) technology, the recognition of new energy vehicles is gradually increasing. As a result, users are paying more and more attention to the safety and reliability of new energy vehicles.
[0003] Motors often face the risk of thermal failure of motor controllers due to stalling. This is mainly manifested in the three-phase IGBT (Insulated Gate Bipolar Transistor) inside the motor controller not switching the switching frequency, causing the IGBT temperature to rise sharply and eventually "explode".
[0004] At present, the control methods for dealing with stalling mainly focus on judging the stalling status based on motor current, motor stator temperature, IGBT temperature, etc. The corresponding post-processing mainly limits the available torque of the motor in stages. These judgment methods and post-processing methods are not comprehensive enough to meet the actual needs of various working conditions, and the safety of the vehicle system cannot be guaranteed.
[0005] Therefore, it is necessary to provide an improved vehicle motor control method, device, motor controller and vehicle to solve the above problems. Summary of the invention
[0006] The present application provides a vehicle motor control method, device, motor controller and vehicle with improved comprehensiveness and reliability.
[0007] The present application discloses a method for controlling a vehicle motor, comprising:
[0008] Get the real-time speed and torque of the motor;
[0009] According to the real-time rotation speed and the real-time torque, determining whether the motor meets a stall condition or a low-speed condition;
[0010] If the motor only meets the stall condition, it is determined that the motor is in a first operating condition, and the maximum available torque of the motor is adjusted according to a first duration, where the first duration is the duration after the motor meets the stall condition;
[0011] If the motor only meets the low-speed condition, determining that the motor is in the second operating condition, and adjusting the maximum available torque of the motor according to the real-time speed;
[0012] If the motor satisfies both the stall condition and the low speed condition, it is determined that the motor is in the third operating condition, and the maximum available torque of the motor is adjusted according to the first duration and the real-time speed.
[0013] By obtaining the motor's speed and torque in real time, the current working condition of the motor can be determined more accurately. Under different working conditions, the maximum available torque of the motor is adjusted to prevent the motor controller from overheating and being damaged.
[0014] Further,
[0015] The stall condition includes a first condition, wherein the first condition is: the real-time rotation speed is less than a first rotation speed threshold, and the real-time torque is greater than a torque threshold;
[0016] The low speed condition is: the real-time speed is less than a second speed threshold; and the second speed threshold is less than the first speed threshold.
[0017] Whether the motor meets the first condition can be determined by the real-time speed and real-time torque, and whether the motor meets the low-speed condition can be determined by the real-time speed. This can provide a more detailed and comprehensive division of the motor's working conditions with strong real-time performance.
[0018] Furthermore, the stall condition further includes a second condition, and the second condition is:
[0019] When the first condition is met, start the first timing, and record the duration of the first timing as the second duration;
[0020] Within a first preset time period after the first timing is started, if the first condition is not met, the first timing is stopped and the second time period is reset to zero;
[0021] When the second time length is equal to the first preset time length, it is determined that the motor meets the second condition.
[0022] By introducing the first timing when the motor meets the first condition, misjudgment caused by abnormal fluctuations of the motor in a short period of time can be prevented, thereby providing an anti-shake function and avoiding frequent switching of protection operations, which can effectively improve the stability and accuracy of the motor stall condition judgment.
[0023] Further, adjusting the maximum available torque of the motor according to the first duration includes:
[0024] According to the first time length, obtaining a first derating factor of the motor torque, wherein the first derating factor decreases linearly with the first time length;
[0025] Comparing the first derating factor with a first preset derating factor;
[0026] Selecting a larger value between the first derating factor and the first preset derating factor as the actual derating factor;
[0027] The maximum available torque of the motor under the first working condition is adjusted according to the actual derating factor and the rated torque of the motor.
[0028] The first derating factor decreases linearly with the first duration, which can achieve more accurate maximum available torque control and effectively avoid overload or damage to the motor controller caused by continuous stalling. At the same time, comparing the first derating factor with the first preset derating factor and selecting the larger value as the actual derating factor helps avoid excessive derating, thereby ensuring that the maximum available torque of the motor under the first working condition is not too low, which helps balance motor protection and performance output.
[0029] Further, adjusting the maximum available torque of the motor according to the real-time rotation speed includes:
[0030] According to the real-time rotation speed, obtaining a second derating factor of the motor torque, wherein the second derating factor decreases linearly with the real-time rotation speed;
[0031] comparing the second derating factor with a second preset derating factor;
[0032] Selecting a larger value between the second derating factor and the second preset derating factor as the actual derating factor;
[0033] The maximum available torque of the motor under the second operating condition is adjusted according to the actual derating factor and the rated torque of the motor.
[0034] The second derating factor decreases linearly with the real-time speed to prevent the risk of damage to the motor controller due to an objective or subjective large torque request and execution when the vehicle is running at too low a speed but not locked. At the same time, the second derating factor is compared with the second preset derating factor, and the larger value is selected as the actual derating factor, which helps to avoid excessive derating, balance motor protection and performance output, and ensure that the maximum potential of the motor can be stably and reasonably exerted under the second working condition.
[0035] Further, adjusting the maximum available torque of the motor according to the first duration and the real-time rotation speed includes:
[0036] According to the real-time rotation speed and the first duration, a third derating factor of the motor torque is obtained, wherein the third derating factor decreases linearly with the real-time rotation speed and / or the first duration;
[0037] Comparing the third derating factor with a third preset derating factor;
[0038] Selecting a larger value between the third derating factor and the third preset derating factor as the actual derating factor;
[0039] The maximum available torque of the motor under the third working condition is adjusted according to the actual derating factor and the rated torque of the motor.
[0040] Under the third working condition, the motor meets both the stall condition and the low-speed condition. Therefore, in the process of adjusting the maximum available torque, the first duration and the real-time speed are comprehensively considered to make the adjustment more accurate and reliable.
[0041] Further, the first duration includes a preset stable duration, and the maximum available torque remains unchanged during the stable duration.
[0042] The maximum available torque remains unchanged within a stable period of time. On the one hand, it is beneficial for the motor to maintain a large performance output within a reasonable range. On the other hand, it provides a buffer time for the driver to avoid a sudden decrease in the maximum available torque of the motor, which would cause a deterioration in the driving experience.
[0043] Furthermore, the method further comprises:
[0044] If the motor exits the first operating condition or the third operating condition, the maximum available torque is restored.
[0045] When the motor recovers to normal state from the first operating condition or the third operating condition, restoring the maximum available torque helps to avoid excessive power limitation, enables the motor to maintain high adaptability in changing operating conditions, and avoids affecting the long-term operating stability of the motor due to excessive protection.
[0046] Further, if the motor is in the first operating condition or the third operating condition, the switching frequency of the IGBT is reduced, and / or a maximum cooling water flow rate is requested.
[0047] Reducing the switching frequency of the IGBT can reduce the heat loss of the IGBT when the motor is stalled. Requesting the maximum cooling water flow can cool the motor to prevent the motor from overheating.
[0048] The present application also discloses a control device for a vehicle motor, comprising:
[0049] Detection module, used to obtain the real-time speed and torque of the motor;
[0050] A judging module, configured to judge whether the motor meets a stall condition or a low speed condition according to the real-time rotation speed and the real-time torque acquired by the detecting module;
[0051] A control module is used to obtain the judgment result of the judgment module and adjust the maximum available torque of the motor according to the judgment result, wherein:
[0052] If the motor only meets the stall condition, it is determined that the motor is in a first operating condition, and the maximum available torque of the motor is adjusted according to a first duration, where the first duration is the duration after the motor meets the stall condition;
[0053] If the motor only meets the low-speed condition, determining that the motor is in the second operating condition, and adjusting the maximum available torque of the motor according to the real-time speed;
[0054] If the motor satisfies both the stall condition and the low speed condition, it is determined that the motor is in the third operating condition, and the maximum available torque of the motor is adjusted according to the first duration and the real-time speed.
[0055] The present application also discloses a motor controller, comprising a memory and a processor;
[0056] The memory is used to store computer programs;
[0057] When the processor is used to execute the computer program, the vehicle motor control method as described above is implemented.
[0058] The present application also discloses a vehicle, comprising the motor controller as described above.
[0059] The vehicle motor control method, device, motor controller and vehicle of the present application can more accurately determine the current working condition of the motor by acquiring the motor speed and torque in real time. When the motor is in the first working condition, the maximum available torque of the motor is adjusted according to the length of time after the motor meets the stall condition to prevent the motor controller from overheating and being damaged. When the motor is in the second working condition, the maximum available torque is adjusted according to the real-time speed to avoid the risk of damage to the motor controller caused by sudden large torque requests. When the motor is in the third working condition, the maximum available torque of the motor is adjusted according to the first duration and the real-time speed to make the adjustment more accurate and reliable. The vehicle motor control method, device, motor controller and vehicle of the present application select the corresponding maximum available torque adjustment method according to the different working conditions of the motor, which can meet the actual needs of various working conditions and better ensure the safety of the entire vehicle system.
[0060] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present specification. BRIEF DESCRIPTION OF THE DRAWINGS
[0061] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the specification and, together with the description, serve to explain the principles of the specification.
[0062] Figure 1 It is a flow chart of the vehicle motor control method of the present application.
[0063] Figure 2 This is a flow chart of adjusting the maximum available torque of the motor of the present application under the first working condition.
[0064] Figure 3 It is a curve diagram of the motor of the present application under the first working condition.
[0065] Figure 4 This is a flow chart of adjusting the maximum available torque of the motor of the present application under the second working condition.
[0066] Figure 5 It is a curve diagram of the motor of the present application under the second working condition.
[0067] Figure 6 This is a flow chart of adjusting the maximum available torque of the motor of the present application under the third working condition.
[0068] Figure 7 It is a curve diagram of the motor of the present application under the third working condition.
[0069] Figure 8 It is a schematic diagram of a control device for a vehicle motor of the present application. DETAILED DESCRIPTION
[0070] Here, the technical solutions in the embodiments (or "implementations") of the present application will be described clearly and completely in conjunction with the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.
[0071] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.
[0072] Next, the embodiments of this specification are described in detail.
[0073] like Figure 1 As shown, the present application provides a method for controlling a vehicle motor, comprising the following steps:
[0074] Step S100: Acquire the real-time speed and real-time torque of the motor.
[0075] The real-time speed of the motor can be detected in real time by a speed sensor, and the real-time torque of the motor can be detected in real time by a torque sensor. In some cases, the real-time speed of the motor can also be calculated by measuring the vehicle speed. This application does not limit the detection method of the real-time speed and real-time torque of the motor.
[0076] Step S200: judging whether the motor meets the stall condition or the low speed condition according to the real-time rotation speed and the real-time torque.
[0077] The stall condition includes a first condition. The first condition is: the real-time speed is less than the first speed threshold, and the real-time torque is greater than the torque threshold. If the real-time speed is less than the first speed threshold, and the real-time torque is greater than the torque threshold, it is determined that the motor meets the first condition.
[0078] The low speed condition is: the real-time rotation speed is less than the second rotation speed threshold. If the real-time rotation speed is less than the second rotation speed threshold, it is determined that the motor meets the low speed condition.
[0079] In some cases, when the motor meets the first condition, it can meet the stall condition and enter the first operating condition.
[0080] This application determines whether the motor meets the first condition of the stall condition by real-time speed and real-time torque, and determines whether the motor meets the low-speed condition by real-time speed. Compared with judging by motor temperature and other methods, it does not need to be affected by the large delay of the temperature sensor, and has strong real-time performance. In addition, by judging the first working condition, the second working condition and the third working condition, the working condition of the motor can be divided more carefully and comprehensively, and the corresponding maximum available torque adjustment method can be selected according to the different working conditions, so that the control method of the vehicle motor is more comprehensive and reliable.
[0081] Among them, the second speed threshold is less than the first speed threshold. That is to say, under the second working condition, the vehicle is running at too low a speed and the motor is not locked. By setting the second speed threshold to be less than the first speed threshold, the working conditions of the motor when running at low speed can be divided more finely, further improving the comprehensiveness and reliability of the vehicle motor control method.
[0082] It is worth noting that in step S200, the determination of whether the motor meets the first condition and the determination of whether the motor meets the low speed condition are performed simultaneously. If the real-time speed is less than the second speed threshold and the real-time torque is greater than the torque threshold, the motor meets both the first condition and the low speed condition.
[0083] The first speed threshold, the second speed threshold and the torque threshold can be preset, and the set values can be flexibly designed according to the actual needs of the vehicle model and the motor. Before the vehicle leaves the factory, the first speed threshold, the second speed threshold and the torque threshold can be determined by experiments. After the vehicle leaves the factory, the first speed threshold, the second speed threshold and the torque threshold can also be updated according to the user's usage data.
[0084] Furthermore, in some embodiments, the stall condition further includes a second condition. The stall condition is satisfied only when the motor satisfies both the first condition and the second condition. When determining whether the motor satisfies the second condition, the following steps are also included:
[0085] Step S201: When a first condition is met, start a first timer, and record the duration of the first timer as a second duration.
[0086] Step S202: within a first preset time period after the first timing is started, if the first condition is not satisfied, the first timing is stopped and the second time period is reset to zero.
[0087] Step S203: When the second time length is equal to the first preset time length, determine that the motor meets the second condition.
[0088] The first preset duration is the anti-shake time when the motor meets the second condition. Only when the real-time speed and real-time torque of the motor meet the first condition and continue to meet the first condition within the first preset duration, will the stall flag position 1 be determined to determine that the motor meets the second condition and meets the stall condition. If within the first preset duration after the first timing is started, the real-time speed and real-time torque of the motor change to not meet the first condition again, the first timing is stopped, and the second duration is reset to zero. When the motor meets the first condition next time, it is re-judged whether the second condition is met.
[0089] By introducing the first timing when the motor meets the first condition, misjudgment caused by abnormal fluctuations of the motor in a short period of time is prevented, thereby providing an anti-shake function, effectively improving the stability and accuracy of the motor stall condition judgment, and avoiding frequent switching of protection operations, thereby improving the working efficiency and service life of the motor.
[0090] Step S300: If the motor only meets the stall condition, it is determined that the motor is in the first working condition, and the maximum available torque of the motor is adjusted according to the first time length. The first time length is the time length after the motor meets the stall condition.
[0091] It can be understood that in step S300, the motor only meets the stall condition but does not meet the low speed condition.
[0092] Specifically, in some cases, such as Figure 2 As shown, step S300 also includes the following steps:
[0093] Step S301: Obtain a first derating factor of the motor torque according to a first duration, wherein the first derating factor decreases linearly with the first duration.
[0094] Step S302: compare the first derating factor with the first preset derating factor.
[0095] Step S303: selecting a larger value between the first derating factor and the first preset derating factor as the actual derating factor.
[0096] Step S304: adjusting the maximum available torque of the motor under the first working condition according to the actual derating factor and the rated torque of the motor.
[0097] The first derating factor decreases linearly with the first duration, so that the maximum available torque of the motor under the first working condition also decreases linearly with the first duration, which can achieve more accurate maximum available torque control and effectively avoid overload or damage to the motor controller caused by continuous stalling. At the same time, comparing the first derating factor with the first preset derating factor and selecting the larger value as the actual derating factor helps avoid excessive derating, thereby ensuring that the maximum available torque of the motor under the first working condition is not too low, which helps balance motor protection and performance output.
[0098] Specifically, the first preset derating factor of this embodiment is 0.52. That is, when the motor enters the first working condition, the maximum available torque of the motor can begin to decrease linearly with the first time length until it decreases to 0.52, and then the derating factor is maintained at 0.52 and no longer changes.
[0099] Further, if the motor is in the first operating condition, the switching frequency of the IGBT is reduced, and / or the maximum cooling water flow rate is requested. Reducing the switching frequency of the IGBT can reduce the heat loss of the IGBT when the motor is locked. Requesting the maximum cooling water flow rate can cool the motor to prevent the motor from overheating.
[0100] In some cases, a corresponding cooling water flow request may be made based on the relationship between the cooling water flow demand of the motor and the real-time speed or real-time torque to more accurately determine the requested cooling water flow and provide better protection for the motor.
[0101] Furthermore, in some embodiments, step S300 further includes the following steps:
[0102] Step S305: If the motor exits the first operating condition, the maximum available torque is restored, and the switching frequency of the IGBT and the cooling water flow request may also be restored.
[0103] It is also possible to set an anti-shake time when the motor no longer meets the stall condition, and then exit the first operating condition after the anti-shake time to restore the maximum available torque, thereby reducing the possibility of misoperation and improving the reliability of the vehicle motor control method.
[0104] When the motor recovers from the first operating condition to the normal operating condition, restoring the maximum available torque helps to avoid excessive power limitation, allowing the motor to maintain a high degree of adaptability in changing operating conditions and avoiding affecting the long-term operating stability of the motor due to excessive protection.
[0105] Further, in some embodiments, the first time period includes a preset stable time period, and the maximum available torque remains unchanged during the stable time period.
[0106] The stabilization time is set at the beginning of the first time, that is, a period of time after the motor enters the first working condition from a non-first working condition. In some cases, the stabilization time is determined according to the heating of the motor controller. During the stabilization time, the heat generated by the motor controller will not cause damage to it. After the motor enters the first working condition, the maximum available torque remains unchanged during the stabilization time. On the one hand, it is beneficial for the motor to maintain a large performance output within a reasonable range. On the other hand, it provides a buffer time for the driver to avoid a sudden decrease in the maximum available torque of the motor, which causes a deterioration in the driving experience.
[0107] In this embodiment, the stabilization time is set to 3.5 seconds, and the maximum available torque of the motor remains unchanged within 3.5 seconds after the motor enters the first working condition. After 3.5 seconds, the maximum available torque of the motor decreases linearly with the first time.
[0108] like Figure 3 As shown, at A, the real-time speed of the motor is less than the first speed threshold (the vehicle speed corresponding to the first speed threshold is 100rpm), and the real-time torque is greater than the torque threshold, and the motor meets the first condition. The time difference from A to B is the second duration. From A to B, the real-time speed of the motor is always less than the first speed threshold, and the real-time torque is always greater than the torque threshold, and the second condition is met at the same time, that is, the stall condition is met. The real-time speed of the motor is always greater than the second speed threshold (the vehicle speed corresponding to the first speed threshold is 63rpm), and the low-speed condition is not met. At B, the stall flag position is 1, and the motor begins to enter the first operating condition.
[0109] The time difference from B to C is the stabilization time (3.5s). From B to C, the actual derating factor of the maximum available torque of the motor remains unchanged, and the maximum available torque of the motor remains unchanged. At C, the actual derating factor begins to change linearly with time. From C to D, the actual derating factor decreases linearly with time, and the maximum available torque of the motor gradually decreases. At D, the actual derating factor drops to be equal to the first preset derating factor (0.52).
[0110] From D to E, the actual derating factor of the motor torque remains unchanged. At E, the motor begins to fail to meet the stall condition. From E to F, the motor never meets the stall condition. At F, the stall flag position is 0, the motor exits the first working condition, the actual derating factor of the motor's maximum available torque begins to recover, and the motor's maximum available torque begins to recover.
[0111] Step S400: If the motor only meets the low-speed condition, it is determined that the motor is in the second operating condition, and the maximum available torque of the motor is adjusted according to the real-time speed.
[0112] It can be understood that in step S400, the real-time speed and real-time torque of the motor only meet the low-speed condition but do not meet the stall condition.
[0113] Specifically, Figure 4 As shown, step S400 also includes the following steps:
[0114] Step S401: Obtain a second derating factor of the motor torque according to the real-time rotation speed, wherein the second derating factor decreases linearly with the real-time rotation speed.
[0115] Step S402: compare the second derating factor with the second preset derating factor.
[0116] Step S403: selecting a larger value between the second derating factor and the second preset derating factor as the actual derating factor.
[0117] Step S404: adjusting the maximum available torque of the motor under the second working condition according to the actual derating factor and the rated torque of the motor.
[0118] The second derating factor decreases linearly with the real-time speed to prevent the risk of damage to the motor controller due to an objective or subjective large torque request and execution when the vehicle is running at too low a speed but not locked. At the same time, the second derating factor is compared with the second preset derating factor, and the larger value is selected as the actual derating factor, which helps to avoid excessive derating, balance motor protection and performance output, and ensure that the maximum potential of the motor can be stably and reasonably exerted under the second working condition.
[0119] Specifically, the second preset derating factor of this embodiment is 0.8. That is, when the real-time speed of the motor is less than the second speed threshold, the maximum available torque of the motor begins to decrease linearly with the real-time speed until it decreases to 0.8, and then the derating factor is maintained at 0.8 and does not change.
[0120] like Figure 5As shown, at G, the real-time speed of the motor is less than the second speed threshold (the second speed threshold corresponds to a vehicle speed of 63rpm), and the motor meets the low-speed condition, but the real-time torque is not greater than the torque threshold, and does not meet the stall condition. The motor begins to enter the second operating condition. From G to H, the actual derating factor of the maximum available torque of the motor decreases linearly with the real-time speed of the motor, and the maximum available torque of the motor gradually decreases. At H, the actual derating factor drops to the same as the second preset derating factor (0.8). After H, the actual derating factor remains unchanged.
[0121] Step S500: If the motor satisfies both the stall condition and the low speed condition, it is determined that the motor is in the third operating condition, and the maximum available torque of the motor is adjusted according to the first duration and the real-time speed.
[0122] In some cases, such as Figure 6 As shown, step S500 also includes the following steps:
[0123] Step S501: Obtain a third derating factor of the motor torque according to the real-time rotation speed and the first duration, wherein the third derating factor decreases linearly with the real-time rotation speed and / or the first duration.
[0124] Step S502: compare the third derating factor with the third preset derating factor, wherein the third preset derating factor is equal to the smaller value of the first preset derating factor and the second preset derating factor.
[0125] Step S503: selecting a larger value between the third derating factor and the third preset derating factor as the actual derating factor.
[0126] Step S504: adjusting the maximum available torque of the motor under the third working condition according to the actual derating factor and the rated torque of the motor.
[0127] Under the third working condition, the motor meets both the stall condition and the low-speed condition. Therefore, in the process of adjusting the maximum available torque, the first duration and the real-time speed are comprehensively considered to make the adjustment more accurate and reliable.
[0128] Furthermore, if the motor is in the third operating condition, the switching frequency of the IGBT is reduced, and / or the maximum cooling water flow rate is requested. Reducing the switching frequency of the IGBT can reduce the heat loss of the IGBT when the motor is stalled. Requesting the maximum cooling water flow rate can cool the motor to prevent the motor from overheating.
[0129] Furthermore, in some embodiments, step S500 further includes the following steps:
[0130] Step S505: If the motor exits the third working condition, the maximum available torque is restored, and the switching frequency of the IGBT and the cooling water flow request can also be restored.
[0131] It is also possible to set an anti-shake time when the motor no longer meets the stall condition, and then exit the third operating condition after the anti-shake time to restore the maximum available torque, thereby reducing the possibility of misoperation and improving the reliability of the vehicle motor control method.
[0132] When the motor recovers from the third operating condition to the normal operating condition, restoring the maximum available torque helps to avoid excessive power limitation, allowing the motor to maintain a high degree of adaptability in changing operating conditions and avoiding affecting the long-term operating stability of the motor due to excessive protection.
[0133] like Figure 7 As shown, at I, the real-time speed of the motor is less than the second speed threshold (the vehicle speed corresponding to the second speed threshold is 63rpm), but the real-time torque is not greater than the torque threshold, the motor meets the low-speed condition and does not meet the stall condition, and begins to enter the second operating condition. From I to J, the actual derating factor of the maximum available torque of the motor decreases linearly with the motor, and the maximum available torque of the motor gradually decreases. At J, the actual derating factor drops to the same as the second preset derating factor (0.8). From J to point, the actual derating factor of the motor torque remains unchanged.
[0134] At K, the real-time torque of the motor is greater than the torque threshold, and the motor satisfies the first condition at the same time. The time difference from K to L is the second duration. From K to L, the motor always satisfies the first condition, and therefore satisfies the second condition at the same time. At L, the motor satisfies both the stall condition and the low speed condition, and enters the third operating condition, with the stall mark position 1. The time difference from L to M is the stable duration (3.5s). From L to M, the actual derating factor of the motor's maximum available torque remains unchanged, and is always maintained equal to the second preset derating factor.
[0135] At M, the actual derating factor begins to change linearly with the first duration and the actual speed of the motor. From M to N, the actual derating factor gradually decreases, and the maximum available torque of the motor gradually decreases. At N, the actual derating factor decreases to be equal to the first preset derating factor (0.52).
[0136] From N to O, the actual derating factor of the motor torque remains unchanged. At O, the motor begins to fail to meet the stall condition. From O to P, the motor never meets the stall condition. At P, the stall flag position is 0, the motor exits the third working condition, the actual derating factor of the motor's maximum available torque begins to recover, and the motor's maximum available torque begins to recover.
[0137] like Figure 8 As shown, the present application also provides a control device for a vehicle motor, comprising:
[0138] The detection module is used to obtain the real-time speed and torque of the motor.
[0139] The judgment module is used to judge whether the motor meets the stall condition or the low speed condition according to the real-time speed and real-time torque obtained by the detection module.
[0140] The control module is used to obtain the judgment result of the judgment module and adjust the maximum available torque of the motor according to the judgment result.
[0141] If the motor only meets the stall condition, it is determined that the motor is in the first operating condition, and the maximum available torque of the motor is adjusted according to the first time length, where the first time length is the time after the motor meets the stall condition.
[0142] If the motor only meets the low-speed condition, it is determined that the motor is in the second operating condition, and the maximum available torque of the motor is adjusted according to the real-time speed.
[0143] If the motor satisfies both the stall condition and the low speed condition, it is determined that the motor is in the third operating condition, and the maximum available torque of the motor is adjusted according to the first duration and the real-time speed.
[0144] The present application also provides a motor controller, comprising a memory and a processor. The memory is used to store a computer program. When the processor is used to execute the computer program, the vehicle motor control method described above is implemented.
[0145] The present application also provides a vehicle, comprising the motor controller as described above.
[0146] The vehicle motor control method, device, motor controller and vehicle of the present application can more accurately determine the current working condition of the motor by acquiring the motor speed and torque in real time. When the motor is in the first working condition, the maximum available torque of the motor is adjusted according to the length of time after the motor meets the stall condition to prevent the motor controller from overheating and being damaged. When the motor is in the second working condition, the maximum available torque is adjusted according to the real-time speed to avoid the risk of damage to the motor controller caused by sudden large torque requests. When the motor is in the third working condition, the maximum available torque of the motor is adjusted according to the first duration and the real-time speed to make the adjustment more accurate and reliable. The vehicle motor control method, device, motor controller and vehicle of the present application select the corresponding maximum available torque adjustment method according to the different working conditions of the motor, which can meet the actual needs of various working conditions and better ensure the safety of the entire vehicle system.
[0147] It should be noted that the technical solutions or technical features described in the above embodiments can be combined or supplemented with each other without causing conflicts. The scope of protection of this application is not limited to the precise structures described in the above embodiments and shown in the drawings; all modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of this application should be included in the scope of protection of this application.
Claims
1. A method for controlling a vehicle motor, characterized in that: include: Get the real-time speed and torque of the motor; According to the real-time rotation speed and the real-time torque, determining whether the motor meets a stall condition or a low-speed condition; If the motor only meets the stall condition, it is determined that the motor is in a first operating condition, and the maximum available torque of the motor is adjusted according to a first duration, where the first duration is the duration after the motor meets the stall condition; If the motor only meets the low-speed condition, determining that the motor is in the second operating condition, and adjusting the maximum available torque of the motor according to the real-time speed; If the motor satisfies both the stall condition and the low speed condition, it is determined that the motor is in the third operating condition, and the maximum available torque of the motor is adjusted according to the first duration and the real-time speed.
2. The vehicle motor control method according to claim 1, characterized in that: The stall condition includes a first condition, wherein the first condition is: the real-time rotation speed is less than a first rotation speed threshold, and the real-time torque is greater than a torque threshold; The low speed condition is: the real-time speed is less than a second speed threshold; and the second speed threshold is less than the first speed threshold.
3. The vehicle motor control method according to claim 2, characterized in that: The stall condition also includes a second condition, which is: When the first condition is met, start the first timing, and record the duration of the first timing as the second duration; Within a first preset time period after the first timing is started, if the first condition is not met, the first timing is stopped and the second time period is reset to zero; When the second time length is equal to the first preset time length, it is determined that the motor meets the second condition.
4. The vehicle motor control method according to claim 1, characterized in that: Adjusting the maximum available torque of the motor according to the first duration includes: According to the first time length, obtaining a first derating factor of the motor torque, wherein the first derating factor decreases linearly with the first time length; Comparing the first derating factor with a first preset derating factor; Selecting a larger value between the first derating factor and the first preset derating factor as the actual derating factor; The maximum available torque of the motor under the first working condition is adjusted according to the actual derating factor and the rated torque of the motor.
5. The vehicle motor control method according to claim 1, characterized in that: Adjusting the maximum available torque of the motor according to the real-time rotation speed includes: According to the real-time rotation speed, obtaining a second derating factor of the motor torque, wherein the second derating factor decreases linearly with the real-time rotation speed; comparing the second derating factor with a second preset derating factor; Selecting a larger value between the second derating factor and the second preset derating factor as the actual derating factor; The maximum available torque of the motor under the second operating condition is adjusted according to the actual derating factor and the rated torque of the motor.
6. The vehicle motor control method according to claim 1, characterized in that: Adjusting the maximum available torque of the motor according to the first duration and the real-time rotation speed includes: According to the real-time rotation speed and the first duration, a third derating factor of the motor torque is obtained, wherein the third derating factor decreases linearly with the real-time rotation speed and / or the first duration; Comparing the third derating factor with a third preset derating factor; Selecting a larger value between the third derating factor and the third preset derating factor as the actual derating factor; The maximum available torque of the motor under the third working condition is adjusted according to the actual derating factor and the rated torque of the motor.
7. The vehicle motor control method according to claim 1, characterized in that: The first time period includes a preset stable time period, and the maximum available torque remains unchanged during the stable time period.
8. The vehicle motor control method according to claim 1, characterized in that: The method further comprises: If the motor exits the first operating condition or the third operating condition, the maximum available torque is restored.
9. The vehicle motor control method according to claim 1, characterized in that: If the motor is in the first operating condition or the third operating condition, the switching frequency of the IGBT is reduced, and / or a maximum cooling water flow rate is requested.
10. A control device for a vehicle motor, characterized in that: include: Detection module, used to obtain the real-time speed and torque of the motor; A judging module, configured to judge whether the motor meets a stall condition or a low speed condition according to the real-time rotation speed and the real-time torque acquired by the detecting module; A control module is used to obtain the judgment result of the judgment module and adjust the maximum available torque of the motor according to the judgment result, wherein: If the motor only meets the stall condition, it is determined that the motor is in a first operating condition, and the maximum available torque of the motor is adjusted according to a first duration, where the first duration is the duration after the motor meets the stall condition; If the motor only meets the low-speed condition, determining that the motor is in the second operating condition, and adjusting the maximum available torque of the motor according to the real-time speed; If the motor satisfies both the stall condition and the low speed condition, it is determined that the motor is in the third operating condition, and the maximum available torque of the motor is adjusted according to the first duration and the real-time speed.
11. A motor controller, characterized in that: including memory and processor; The memory is used to store computer programs; When the processor is used to execute the computer program, the method for controlling a vehicle motor according to any one of claims 1 to 9 is implemented.
12. A vehicle, characterized in that: Comprising the motor controller of claim 11.