Motor drive control method, motor controller and computer readable storage medium

Abstract

The present application discloses a motor drive control method, device and computer-readable storage medium, and relates to the field of motor control technology. In the present application, a comparison result of a first ratio of a motor speed sampling value to a bus voltage sampling value and a second ratio of a maximum motor speed to a minimum bus voltage in a motor control mapping table is obtained in response to an electric drive undervoltage signal; a first operating strategy is generated in response to the result that the first ratio is less than or equal to the second ratio; a second operating strategy is generated in response to the result that the first ratio is greater than the second ratio, and the maximum motor speed in the second operating strategy is less than the maximum motor speed in the first operating strategy. The present application explores space for motor driving in the case of electric drive undervoltage, so that braking protection is not directly forced in the case of electric drive undervoltage, thereby improving endurance and driving capabilities.

Description

Technical Field

[0001] The present application relates to the field of motor control technology, and in particular to a motor drive control method, device and computer-readable storage medium. Background Art

[0002] Electric vehicle range anxiety is an issue that consumers are particularly concerned about before choosing an electric vehicle. When the electric drive bus voltage drops, it is very easy to cause serious undervoltage-related faults in the electric drive system. In order to prevent the electric drive from losing control when the motor operates in an uncalibrated voltage area, forced braking protection will be performed, resulting in poor electric vehicle range. Summary of the invention

[0003] One of the embodiments of the present application provides a motor drive control method, including: in response to an electric drive undervoltage signal, obtaining a comparison result of a first ratio of a motor speed sampling value to a bus voltage sampling value and a second ratio of a maximum motor speed to a minimum bus voltage in a motor control mapping table, wherein the motor control mapping table is a mapping table between motor torque, bus voltage, motor speed and motor current; in response to a result that the first ratio is less than or equal to the second ratio, generating a first operating strategy; in response to a result that the first ratio is greater than the second ratio, generating a second operating strategy, wherein the maximum motor speed in the second operating strategy is less than the maximum motor speed in the first operating strategy.

[0004] A further embodiment is that the second operating strategy includes an active protection strategy, and the motor in the active protection strategy is in a shutdown state; the second operating strategy is generated in response to the result that the first ratio is greater than the second ratio, including: generating the active protection strategy in response to the result that the first ratio is greater than the second ratio.

[0005] A further embodiment is that the second operating strategy includes a speed limit strategy; the second operating strategy is generated in response to the result that the first ratio is greater than the second ratio, including: obtaining the weakening magnetic angle of the motor sampling current in response to the result that the first ratio is greater than the second ratio; generating the speed limit strategy in response to the result that the weakening magnetic angle is less than or equal to the maximum allowable weakening magnetic angle of the motor.

[0006] A further embodiment is that the motor speed in the speed limit strategy is equal to the product of the second ratio and the bus voltage sampling value.

[0007] A further embodiment is that the second operating strategy also includes an active protection strategy, and the motor in the active protection strategy is in a shutdown state; the second operating strategy is generated in response to the result that the first ratio is greater than the second ratio, and also includes: generating an active protection strategy in response to the result that the weakening magnetic angle is greater than the maximum allowable weakening magnetic angle of the motor.

[0008] A further embodiment is that before obtaining a comparison result of a first ratio of a motor speed sampling value to a bus voltage sampling value and a second ratio of a maximum motor speed to a minimum bus voltage in a motor control mapping table in response to an electric drive undervoltage signal, the method also includes: generating an electric drive undervoltage signal in response to a result that the motor line voltage sampling value is less than a motor line voltage threshold.

[0009] In a further embodiment, the method further comprises: generating an electric drive non-undervoltage signal in response to a result that the motor line voltage sampling value is greater than or equal to the motor line voltage threshold.

[0010] A further embodiment is that the method further includes: generating a table lookup control strategy in response to an electric drive non-undervoltage signal, wherein the motor current in the table lookup control strategy is the motor current in the motor control mapping table.

[0011] One of the embodiments of the present application provides a motor drive control method, including: obtaining the weakening magnetic angle of the motor sampling current and the maximum allowable weakening magnetic angle of the motor in response to an electric drive undervoltage signal; generating an active protection strategy in response to the result that the weakening magnetic angle of the motor sampling current is greater than the maximum allowable weakening magnetic angle of the motor, and the motor in the active protection strategy is in a shutdown state.

[0012] A further embodiment is that the method also includes: in response to the electric drive undervoltage signal, obtaining a comparison result of a first ratio of a motor speed sampling value to a bus voltage sampling value and a second ratio of a maximum motor speed to a minimum bus voltage in a motor control mapping table, wherein the motor control mapping table is a mapping table between motor torque, bus voltage, motor speed and motor current; in response to the result that the first ratio is less than or equal to the second ratio and the weak magnetic angle is less than or equal to the maximum allowable weak magnetic angle of the motor, generating a speed limit strategy, the maximum current in the speed limit strategy being less than the maximum motor current in the motor control mapping table.

[0013] A further embodiment is that the motor speed in the speed limit strategy is equal to the product of the second ratio and the bus voltage sampling value.

[0014] One of the embodiments of the present application provides a motor controller, including: a sampling module, used to obtain motor speed sampling values ​​and bus voltage sampling values; a storage module, used to store a motor control mapping table, the motor control mapping table being a mapping table between motor torque, bus voltage, motor speed and motor current; a processing module, used to obtain a comparison result of a first ratio of the motor speed sampling value to the bus voltage sampling value and a second ratio of the maximum motor speed to the minimum bus voltage in the motor control mapping table in response to an electric drive undervoltage signal, and used to generate a first operating strategy in response to a result that the first ratio is less than or equal to the second ratio, and used to generate a second operating strategy in response to a result that the first ratio is greater than the second ratio, the maximum motor speed in the second operating strategy being less than the maximum motor speed in the first operating strategy.

[0015] One of the embodiments of the present application provides a motor controller, including: a sampling module, used to obtain a motor sampling current in response to an electric drive undervoltage signal; a storage module, used to store a maximum allowable magnetic weakening angle of the motor; a processing module, used to generate an active protection strategy in response to a result that the magnetic weakening angle of the motor sampling current is greater than the maximum allowable magnetic weakening angle of the motor, and the motor in the active protection strategy is in a shutdown state.

[0016] One of the embodiments of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described above is implemented.

[0017] The present application adopts the above-mentioned technical solution to create space for motor driving in the case of electric drive under-voltage, so that braking protection is not directly forced in the case of electric drive under-voltage, thereby improving the endurance and driving capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a flow chart of the control method in some embodiments of the present application;

[0019] Figure 2 Flow chart of control methods in other embodiments of the present application;

[0020] Figure 3 A schematic diagram of a motor controller in some embodiments of the present application;

[0021] Figure 4 It is a schematic diagram of the framework of a computer-readable storage medium in one embodiment of the present application. DETAILED DESCRIPTION

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0023] This application describes a motor drive control method, which can be used to achieve control of the motor. In the case of electric drive undervoltage (usually refers to the situation where the voltage provided by the battery is lower than the rated voltage), there is still room for motor drive, so that braking protection is not directly forced, thereby improving the endurance and driving ability. The method can also be used for equipment including motors, such as electric vehicles, air conditioners, fans and washing machines, and can drive and control the motor. Here, the equipment including the motor is an electric vehicle as an example.

[0024] The electric vehicle may include a pure electric vehicle, a plug-in hybrid electric vehicle, a fuel cell vehicle, etc. In some embodiments, the motor may be a permanent magnet synchronous motor (PMSM).

[0025] See also Figure 1 , Figure 1 1 is a flow chart of a control method in some embodiments of the present application. The method can be used in a motor controller to control the motor through the motor controller. The method may include:

[0026] Step S101: generating an electric drive undervoltage signal in response to a result that a motor line voltage sampling value is less than a motor line voltage threshold.

[0027] In motor analysis, d-axis current and q-axis current are used to describe the components of motor current in the dq coordinate system (also called the "synchronous rotating coordinate system"). The dq coordinate system is a method of converting a three-phase AC system into an equivalent DC system.

[0028] Among them, the d-axis current (I d ): The d-axis current has the same direction as the d-axis magnetic field, which is of great significance in analyzing the magnetic field and torque characteristics of the motor. For example, in a permanent magnet synchronous motor, the magnitude of the d-axis current will affect the magnetic field strength of the motor, thereby affecting the torque generation and the motor's operating performance.

[0029] q-axis current (I q): The direction of the q-axis current is 90 degrees different from that of the q-axis magnetic field. In terms of torque control, the q-axis current often plays a key role. For example, when the servo control is used for torque control, the q-axis current is referenced. By controlling the size of the q-axis current, the output torque of the motor can be effectively controlled.

[0030] The motor line voltage changes with the motor speed and dq axis current. When the current tends to be stable and the influence of stator resistance is ignored, the motor line voltage and dq axis current can have the following relationship:

[0031]

[0032] Among them, U s is the motor line voltage, n rpm is the motor speed, k is the coefficient for converting the motor speed into electrical angle, L d is the d-axis motor inductance in the dq coordinate system, L q is the q-axis motor inductance in the dq coordinate system, I d is the d-axis motor current in the dq coordinate system, I q is the q-axis motor current in the dq coordinate system.

[0033] The maximum voltage that can be used in the motor controller, that is, the maximum value of the motor line voltage, can have the following relationship:

[0034]

[0035] Among them, U s-max is the maximum value of the motor line voltage, α is the voltage utilization rate, U dc is the bus voltage sampling value.

[0036] In actual situations, U can be equivalently obtained through the current regulator during current loop control. dq (For example, the d-axis motor voltage U in the dq coordinate system d and q-axis motor voltage U q ), and thus the motor line voltage

[0037] When the electric drive is undervoltage, U s will be greater than U s-max , when the electric drive is not undervoltage, U s Will be less than or equal to U s-max . Then the motor line voltage U s The maximum value of the motor line voltage U s-max Compare and determine whether the electric drive is undervoltage.

[0038] In some embodiments, the motor line voltage sampling value may be the motor line voltage maximum value U s-max , and can be calculated by the motor controller; the motor line voltage threshold can be the motor line voltage Us , and can be pre-stored in the motor controller. In some scenarios, the motor line voltage threshold can be the motor line voltage U s , and can be calculated by the motor controller. Furthermore, in some scenarios, before step S101, it is necessary to perform the following steps: sampling the data involved in the current regulator, and then calculating U dq .

[0039] In some embodiments, the motor line voltage threshold can be obtained by s The motor line voltage threshold may be greater than the motor line voltage U s In some embodiments, the motor line voltage threshold may be less than the motor line voltage U s .

[0040] In some embodiments, based on the maximum motor line voltage U s-max In order to meet the needs, before step S101, it is also necessary to perform the step of sampling the bus voltage to obtain the bus voltage sampling value. Of course, the bus voltage sampling value can also be calculated from other sampled data such as current, line current and other data. The specific calculation process can be executed by the motor controller.

[0041] In some embodiments, the process of determining whether the electric drive is under-voltage may not be performed through step S101, but may be determined by the voltage sampling value of the power source, such as a battery, and the voltage threshold of the power source, such as a battery. For example, if the voltage sampling value of the power source, such as a battery, is less than the voltage threshold of the power source, such as a battery, it can be determined that the electric drive is under-voltage; for example, if the voltage sampling value of the power source, such as a battery, is greater than or equal to the voltage threshold of the power source, such as a battery, it can be determined that the electric drive is not under-voltage. In some scenarios, the voltage sampling value of the battery can be obtained by sampling. In some scenarios, the voltage threshold of the power source, such as a battery, can be pre-stored in the motor controller.

[0042] In some embodiments, the motor line voltage threshold may be obtained by adjusting the voltage threshold of a power source such as a battery, and may be pre-stored in the motor controller, and may be specifically set by those skilled in the art as needed, and will not be described in detail. In some embodiments, the motor line voltage threshold may be greater than the voltage threshold of a power source such as a battery. In some embodiments, the motor line voltage threshold may be less than the voltage threshold of a power source such as a battery.

[0043] In some embodiments, the motor controller may generate an electric drive undervoltage signal or an electric drive no undervoltage signal by determining whether the electric drive is undervoltage.

[0044] It can be understood that the above method of determining whether the electric drive is under-voltage is only an example, and a technical solution well known in the art may also be used to determine whether the electric drive is under-voltage.

[0045] Step S102: obtaining a comparison result of the first ratio and the second ratio in response to the electric drive undervoltage signal.

[0046] Among them, the first ratio can be the ratio of the motor speed sampling value to the bus voltage sampling value, and the second ratio can be the ratio of the maximum motor speed to the minimum bus voltage in the motor control mapping table. In addition, the motor control mapping table is a mapping table between motor torque, bus voltage, motor speed and motor current, which can be obtained according to technical solutions well known in the art, or obtained according to actual experiments, and will not be elaborated on.

[0047] The motor controller can control the motor through the motor control mapping table when executing the table lookup control strategy. For example, the motor controller obtains the user's requirements for the motor, such as bus voltage, motor torque and motor speed, and then the motor controller can obtain the motor current corresponding to the bus voltage, motor torque and motor speed in the motor control mapping table, and further input the motor current into the motor to achieve control.

[0048] In some embodiments, the user's demand for the motor, such as bus voltage, motor torque, and motor speed, can be obtained by real-time sampling to form bus voltage sampling values, motor torque sampling values, and motor speed sampling values. In some scenarios, among bus voltage, motor torque, and motor speed, only motor torque can be obtained by the user's demand for the motor, such as the user using the accelerator pedal of an electric vehicle. The bus voltage and motor speed can be obtained by the motor controller sampling the motor in real time or when needed.

[0049] When the bus voltage sampling value does not appear in the motor control mapping table, the table lookup control strategy cannot be performed. In some scenarios, the electric drive undervoltage will cause the bus voltage sampling value to not be recorded in the motor control mapping table. In some scenarios, when the motor controller and / or motor or battery fails, the bus voltage sampling value may not be recorded in the motor control mapping table.

[0050] Furthermore, in some embodiments, the electric drive undervoltage in step S101 can be determined by the bus voltage sampling value not appearing on the motor control mapping table. In some embodiments, the electric drive is not undervoltage in step S101 by the bus voltage sampling value appearing on the motor control mapping table.

[0051] When the table lookup control strategy cannot be performed, the motor controller needs to form a new operation strategy to perform electric drive. In some scenarios, it can be considered that a new operation strategy is needed when the electric drive is undervoltage, so as to directly replace the active protection strategy and tap into the space for motor drive, so that in the case of electric drive undervoltage, braking protection (i.e., active protection strategy) is not directly forced, thereby improving the endurance and driving capabilities. Among them, the motor in the active protection strategy is in a shutdown state.

[0052] In some embodiments, calculation of the first ratio, calculation of the second ratio, and comparison result of the first ratio and the second ratio can all be implemented by a motor controller.

[0053] If the relationship between the motor voltage and the motor speed in the motor control mapping table exceeds the limit, it means that the existing motor control mapping table has been used to its limit, and the second ratio limit can be considered as a limit for safe operation. Then, the first ratio can be compared with the second ratio to determine whether the current motor operation state is safe. In some scenarios, it can be considered that the setting of the second ratio allows for motor drive in the case of undervoltage in the electric drive, thereby improving endurance and driving capabilities.

[0054] Step S103: generating a first operation strategy in response to the result that the first ratio is less than or equal to the second ratio.

[0055] When the first ratio is less than or equal to the second ratio, it can be considered that the operating state of the motor is still in a safe state, and then the motor can be operated according to the first operating strategy.

[0056] In some embodiments, the first operation strategy may be that the motor speed remains unchanged to achieve normal driving of the motor. In some embodiments, the first operation strategy may be a table lookup control strategy, and a table with a mapping relationship between motor speed, motor current and motor torque suitable for the electric drive undervoltage condition may be obtained according to actual experiments to achieve normal driving of the motor. In some embodiments, the first operation strategy may be a given strategy for the motor controller to specify the current to the motor. In some embodiments, the first operation strategy may be a given strategy based on the given current of the speed loop in the speed control mode of the motor controller. In some embodiments, the current in the given strategy and the motor torque (such as the user's demand for the motor) may form a mapping relationship. In some embodiments, the first operation strategy may be a speed limit strategy, which performs speed limit control on the current motor speed, for example, through a speed limit table with a mapping relationship between the motor speed, motor current and motor torque, the motor current is controlled by the user's motor torque demand for the motor, and of course, the current corresponding to the motor speed demand may be determined according to the corresponding formula according to the user's motor torque demand for the motor. In some other embodiments, the first operation strategy may be a speed limit strategy determined based on the speed loop in the speed control mode of the motor controller, which performs speed limit control on the current motor speed. It can be understood that the above-mentioned first operation strategy is only an example, and the first operation strategy can also be determined by a technical solution well known in the art, which will not be elaborated herein.

[0057] It is understandable that after step S103, the step of obtaining the comparison result between the first ratio and the second ratio may be continued. Then, in a further embodiment, the execution of step S103 or step S104 may be determined according to the comparison result.

[0058] Step S104: generating a second operation strategy in response to the result that the first ratio is greater than the second ratio.

[0059] If the relationship between the motor voltage and the motor speed in the motor control mapping table exceeds the limit, it means that the existing motor control mapping table has been used to its limit, and the second ratio limit can be considered as a limit for safe operation. Then, the first ratio can be compared with the second ratio to determine whether the current motor operation state is safe. In some scenarios, it can be considered that the setting of the second ratio allows for motor drive in the case of undervoltage in the electric drive, thereby improving endurance and driving capabilities.

[0060] When the first ratio is greater than the second ratio, it can be considered that the motor operating state is in an unsafe state, and then it can be operated according to the second operating strategy, so that the maximum motor speed in the second operating strategy is less than the maximum motor speed in the first operating strategy, thereby completing speed limit control.

[0061] In some embodiments, the second operation strategy may be an active protection strategy, so that the motor is in a shutdown state. That is, step S104 may include generating an active protection strategy in response to the result that the first ratio is greater than the second ratio.

[0062] In some embodiments, the second operation strategy may include a speed limit strategy and an active protection strategy. That is, the motor controller may restrict the speed limit strategy and then execute the active protection strategy. In some scenarios, step S104 may include generating a speed limit strategy and an active protection strategy in response to the result that the first ratio is greater than the second ratio, so as to execute the active protection strategy after executing the speed limit strategy.

[0063] In some embodiments, when the first operating strategy is a speed limit strategy and the second operating strategy includes a speed limit strategy, step S103 and step S104 can be replaced by: generating a speed limit strategy and an active protection strategy in response to the result that the first ratio is less than or equal to the second ratio, so as to execute the active protection strategy after executing the speed limit strategy.

[0064] In some embodiments, step S104 may include:

[0065] Step S1041: in response to the result that the first ratio is greater than the second ratio, obtaining the weakening magnetic angle of the motor sampling current.

[0066] Step S1042: generating a speed limit strategy in response to the result that the magnetic weakening angle is less than or equal to the maximum allowable magnetic weakening angle of the motor.

[0067] Step S1043: generating an active protection strategy in response to the result that the magnetic field weakening angle is greater than the maximum allowable magnetic field weakening angle of the motor.

[0068] The weakening magnetic angle of the current affects the control of the motor. Therefore, it is necessary to determine whether the motor is still within the controllable range through the weakening magnetic angle of the current. If the weakening magnetic angle of the current exceeds the maximum allowable weakening magnetic angle, the motor's control accuracy and torque output will be too poor, and it will not be able to support normal operation, and an active protection strategy must be implemented immediately. If the weakening magnetic angle of the current does not exceed the maximum allowable weakening magnetic angle, it can further expand the space for motor driving in the case of electric drive undervoltage, and improve endurance and driving capabilities.

[0069] In some embodiments, the motor speed in the speed limit strategy may be equal to the product of the second ratio and the bus voltage sampling value.

[0070] In some embodiments, the speed limit strategy in the first operation strategy may be the speed limit strategy in step S1042. In some embodiments, after step S101 or other methods of determining whether the electric drive is undervoltage, step S103 and step S104 may not be performed, and the step of obtaining the weakening magnetic angle of the motor sampling current and the maximum allowable weakening magnetic angle of the motor in response to the electric drive undervoltage signal may be performed directly. Step S1042 and / or step S1043 may also be performed in further embodiments.

[0071] It is understandable that the step of obtaining the weakening magnetic angle of the motor sampling current may be continued after step S1042. Then, in a further embodiment, the execution of step S1042 or step S1043 may be determined according to the comparison result.

[0072] See also Figure 2 , Figure 2 This is a flow chart of a control method in some other embodiments of the present application. The method may include:

[0073] Step S201: generating an electric drive no under-voltage signal in response to a result that the motor line voltage sampling value is greater than or equal to the motor line voltage threshold.

[0074] Step S202: generating a table lookup control strategy in response to the electric drive non-undervoltage signal.

[0075] The motor current in the table lookup control strategy is the motor current in the motor control mapping table.

[0076] It is understandable that the step of obtaining the motor line voltage sampling value and the motor line voltage threshold may be performed before step S201. Then, in a further embodiment, step S101 or step S201 may be performed. And the step of obtaining the motor line voltage sampling value and the motor line voltage threshold may be performed after step S202. Then, the execution of step S101 or step S201 may be determined. In some scenarios, the step of obtaining the motor line voltage sampling value and the motor line voltage threshold may be performed after step S102. The execution of step S101 or step S201 may be performed.

[0077] Next, another control method is described. This method can be used to control the motor. In the case of undervoltage of the electric drive (usually refers to the situation where the voltage provided by the battery is lower than the rated voltage), there is still room for motor driving, so that braking protection is not directly forced, thereby improving the endurance and driving ability. This method can also be used for equipment including motors, such as electric vehicles, air conditioners, fans and washing machines, and can drive and control the motors. Here, the equipment including the motor is an electric vehicle as an example.

[0078] The method may be used in a motor controller to control the motor through the motor controller. The method may include:

[0079] Step S301: acquiring the weakening magnetic angle of the motor sampling current and the maximum allowable weakening magnetic angle of the motor in response to the electric drive undervoltage signal.

[0080] Step S302: generating an active protection strategy in response to the result that the magnetic weakening angle of the motor sampling current is greater than the maximum allowable magnetic weakening angle of the motor.

[0081] In some embodiments, the method may further include:

[0082] Step S303: obtaining a comparison result of the first ratio and the second ratio in response to the electric drive undervoltage signal.

[0083] Step S304: generating a speed limit strategy in response to the result that the first ratio is less than or equal to the second ratio and the magnetic weakening angle is less than or equal to the maximum allowable magnetic weakening angle of the motor.

[0084] It can be understood that the introduction of step S301, step S302, step S303, and step S304 in the method can refer to the introduction of the above method and will not be repeated here.

[0085] Next, a motor controller is described, which can apply the above-described method. Figure 3 , Figure 3 The motor controller 300 may include a sampling module 301 , a storage module 302 , and a processing module 303 coupled to the sampling module 301 and the storage module 302 .

[0086] In some embodiments, the sampling module 301 is used to obtain the motor speed sampling value and the bus voltage sampling value;

[0087] In some embodiments, the storage module 302 is used to store a motor control mapping table, which is a mapping table between motor torque, bus voltage, motor speed, and motor current;

[0088] In some embodiments, the processing module 303 is configured to compare the first ratio with the second ratio.

[0089] In some embodiments, the processing module 303 is used to obtain a comparison result of a first ratio of a motor speed sampling value to a bus voltage sampling value and a second ratio of a maximum motor speed to a minimum bus voltage in a motor control mapping table in response to an electric drive undervoltage signal, and to generate a first operating strategy in response to a result that the first ratio is less than or equal to the second ratio, and to generate a second operating strategy in response to a result that the first ratio is greater than the second ratio, and the maximum motor speed in the second operating strategy is less than the maximum motor speed in the first operating strategy.

[0090] In some embodiments, the processing module 303 is configured to generate an active protection strategy in response to a result that the first ratio is greater than the second ratio.

[0091] In some embodiments, the sampling module 301 is used to obtain a sampled current of the motor.

[0092] In some embodiments, the processing module 303 is configured to obtain a magnetic weakening angle of the motor sampling current in response to a result that the first ratio is greater than the second ratio.

[0093] In some embodiments, the storage module 302 is used to store the maximum allowable field weakening angle of the motor.

[0094] In some embodiments, the processing module 303 is used to compare the field weakening angle with the maximum allowable field weakening angle of the motor.

[0095] In some embodiments, the processing module 303 is configured to generate a speed limit strategy in response to a result that the field weakening angle is less than or equal to a maximum allowable field weakening angle of the motor.

[0096] In some embodiments, the processing module 303 is used to calculate the motor speed in the speed limit strategy, where the motor speed in the speed limit strategy is equal to the product of the second ratio and the bus voltage sampling value.

[0097] In some embodiments, the processing module 303 is configured to generate an active protection strategy in response to a result that the field weakening angle is greater than a maximum allowable field weakening angle of the motor.

[0098] In some embodiments, the storage module 302 is configured to store a motor line voltage threshold.

[0099] In some embodiments, the sampling module 301 is used to obtain a sampling value of the motor line voltage.

[0100] In some embodiments, the processing module 303 is used to calculate the motor line voltage sampling value.

[0101] In some embodiments, the processing module 303 is configured to generate an electric drive undervoltage signal in response to a result that the motor line voltage sampling value is less than a motor line voltage threshold.

[0102] In some embodiments, the processing module 303 is used to compare the motor line voltage sampling value with the motor line voltage threshold.

[0103] In some embodiments, the processing module 303 is configured to generate an electric drive non-undervoltage signal in response to a result that the motor line voltage sampling value is greater than or equal to a motor line voltage threshold.

[0104] In some embodiments, the processing module 303 is used to generate a table lookup control strategy in response to the electric drive non-undervoltage signal, and the motor current in the table lookup control strategy is the motor current in the motor control mapping table.

[0105] See also Figure 3 The sampling module 301 is used to obtain the motor sampling current in response to the electric drive undervoltage signal. The storage module 302 is used to store the maximum allowable weak magnetic angle of the motor. The processing module 303 is used to generate an active protection strategy in response to the result that the weak magnetic angle of the motor sampling current is greater than the maximum allowable weak magnetic angle of the motor, and the motor in the active protection strategy is in a shutdown state.

[0106] In some embodiments, the processing module 303 is used to compare the magnetic weakening angle of the motor sampling current with the maximum allowable magnetic weakening angle of the motor.

[0107] In some embodiments, the processing module 303 is used to generate a speed limit strategy in response to the result that the first ratio is less than or equal to the second ratio and the weakening magnetic angle is less than or equal to the maximum allowable weakening magnetic angle of the motor, and the maximum current in the speed limit strategy is less than the maximum motor current in the motor control mapping table.

[0108] The following describes a computer readable storage medium. Figure 4 , Figure 4 The computer-readable storage medium 400 is a schematic diagram of a framework of a computer-readable storage medium in an embodiment of the present application. A computer program 401 is stored on the computer-readable storage medium 400, and the computer program 401 implements the above method when executed by a processor.

[0109] The computer-readable storage medium 400 may specifically be a medium that can store the computer program 401, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, or may be a server that stores the computer program 401. The server may send the stored computer program 401 to other devices for execution, or may also execute the stored computer program 401 by itself.

[0110] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only for example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0111] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "one embodiment" and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in the present application does not necessarily refer to the same embodiment. In addition, certain features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0112] In addition, unless explicitly stated in the claims, the order of processing elements and sequences, the use of alphanumeric characters, or the use of other names in the present application are not intended to limit the order of the processes and methods of the present application. Although the above disclosure discusses some embodiments currently considered useful through various examples, it should be understood that such details are only for illustrative purposes, and the attached claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that are consistent with the essence and scope of the embodiments of the present application. For example, although the system components described above can be implemented by hardware devices, they can also be implemented only by software solutions, such as installing the described system on an existing server or mobile device.

[0113] Similarly, it should be noted that in order to simplify the description disclosed in this application and thus help understand one or more embodiments, in the above description of the embodiments of this application, multiple features are sometimes combined into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0114] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in this application are approximate values, which may change according to the required characteristics of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining the digits. Although the numerical domains and parameters used to confirm the breadth of the range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values ​​is as accurate as possible within the feasible range.

[0115] Each patent, patent application, patent application disclosure, and other materials, such as articles, books, applications, publications, documents, etc., cited in this application are hereby incorporated by reference in their entirety. Except for application history documents that are inconsistent with or conflicting with the content of this application, documents that limit the broadest scope of the claims of this application (currently or later attached to this application) are also excluded. It should be noted that if the description, definition, and / or use of terms in the attached materials of this application are inconsistent or conflicting with the content of this application, the description, definition, and / or use of terms in this application shall prevail.

[0116] Finally, it should be understood that the embodiments in this application are only used to illustrate the principles of the embodiments of this application. Other variations may also fall within the scope of this application. Therefore, as an example and not a limitation, the alternative configurations of the embodiments of this application may be considered to be consistent with the teachings of this application. Accordingly, the embodiments of this application are not limited to the embodiments explicitly introduced and described in this application.

Claims

1. A motor drive control method, characterized in that: include: In response to the electric drive undervoltage signal, obtaining a comparison result of a first ratio of a motor speed sampling value to a bus voltage sampling value and a second ratio of a maximum motor speed to a minimum bus voltage in a motor control mapping table, wherein the motor control mapping table is a mapping table between motor torque, bus voltage, motor speed and motor current; generating a first operation strategy in response to a result that the first ratio is less than or equal to the second ratio; In response to the result that the first ratio is greater than the second ratio, a second operation strategy is generated, wherein the maximum motor speed in the second operation strategy is less than the maximum motor speed in the first operation strategy.

2. The method according to claim 1, characterized in that The second operation strategy includes an active protection strategy, in which the motor is in a shutdown state; The generating a second operation strategy in response to the result that the first ratio is greater than the second ratio comprises: The active protection strategy is generated in response to a result that the first ratio is greater than the second ratio.

3. The method according to claim 1, characterized in that The second operation strategy includes a speed limit strategy; The generating a second operation strategy in response to the result that the first ratio is greater than the second ratio comprises: In response to the result that the first ratio is greater than the second ratio, acquiring a weakening magnetic angle of a motor sampling current; A speed limiting strategy is generated in response to a result that the field weakening angle is less than or equal to a maximum allowable field weakening angle of the motor.

4. The method according to claim 3, characterized in that The motor speed in the speed limit strategy is equal to the product of the second ratio and the bus voltage sampling value.

5. The method according to claim 3 or 4, characterized in that: The second operation strategy also includes an active protection strategy, in which the motor is in a shutdown state; The generating a second operation strategy in response to the result that the first ratio is greater than the second ratio further includes: An active protection strategy is generated in response to a result that the field weakening angle is greater than a maximum allowable field weakening angle of the electric machine.

6. The method according to claim 1, characterized in that Before obtaining a comparison result of a first ratio of a motor speed sampling value to a bus voltage sampling value and a second ratio of a maximum motor speed to a minimum bus voltage in a motor control mapping table in response to an electric drive undervoltage signal, the method further includes: In response to the result that the motor line voltage sampling value is less than the motor line voltage threshold, an electric drive undervoltage signal is generated.

7. The method according to claim 6, characterized in that The method further comprises: In response to the result that the motor line voltage sampling value is greater than or equal to the motor line voltage threshold, an electric drive no under-voltage signal is generated.

8. The method according to claim 1, characterized in that The method further comprises: A table lookup control strategy is generated in response to the electric drive non-undervoltage signal, wherein the motor current in the table lookup control strategy is the motor current in the motor control mapping table.

9. A motor drive control method, characterized in that: include: In response to the electric drive undervoltage signal, obtaining the weakening magnetic angle of the motor sampling current and the maximum allowable weakening magnetic angle of the motor; In response to a result that the weakening magnetic angle of the motor sampling current is greater than the maximum allowable weakening magnetic angle of the motor, an active protection strategy is generated, in which the motor is in a shutdown state.

10. The method according to claim 9, characterized in that The method further comprises: In response to the electric drive undervoltage signal, a comparison result of a first ratio of a motor speed sampling value to a bus voltage sampling value and a second ratio of a maximum motor speed to a minimum bus voltage in a motor control mapping table is obtained, wherein the motor control mapping table is a mapping table between motor torque, bus voltage, motor speed and motor current; A speed limit strategy is generated in response to the result that the first ratio is less than or equal to the second ratio and the weakening magnetic angle is less than or equal to the maximum allowable weakening magnetic angle of the motor, wherein the maximum current in the speed limit strategy is less than the maximum motor current in the motor control mapping table.

11. The method according to claim 10, characterized in that The motor speed in the speed limit strategy is equal to the product of the second ratio and the bus voltage sampling value.

12. A motor controller, characterized in that: include: Sampling module, used to obtain motor speed sampling value and bus voltage sampling value; A storage module, used for storing a motor control mapping table, wherein the motor control mapping table is a mapping table between motor torque, bus voltage, motor speed and motor current; A processing module is used to obtain a comparison result of a first ratio of the motor speed sampling value to the bus voltage sampling value and a second ratio of the maximum motor speed to the minimum bus voltage in the motor control mapping table in response to an electric drive undervoltage signal, and to generate a first operating strategy in response to a result that the first ratio is less than or equal to the second ratio, and to generate a second operating strategy in response to a result that the first ratio is greater than the second ratio, and the maximum motor speed in the second operating strategy is less than the maximum motor speed in the first operating strategy.

13. A motor controller, characterized in that: include: A sampling module, used for obtaining a motor sampling current in response to an electric drive undervoltage signal; A storage module, used to store the maximum allowable weak magnetic angle of the motor; The processing module is used to generate an active protection strategy in response to the result that the weakening magnetic angle of the motor sampling current is greater than the maximum allowable weakening magnetic angle of the motor, and the motor in the active protection strategy is in a shutdown state.

14. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 11 is implemented.

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