阅读说明：本技术 同步电机齿槽转矩标定的方法、装置及电子设备 (Synchronous motor cogging torque calibration method and device and electronic equipment ) 是由 李明洋 刘博峰 吴为 朱春晓 于 2021-09-02 设计创作，主要内容包括：本申请实施例提供一种同步电机齿槽转矩标定的方法、装置及电子设备,其中,针对每个旋转周期,在同步电机低速运行下,获取同步电机的特征倍频值和电机转速；根据特征倍频值和电机转速设定多个滤波函数；基于多个滤波函数计算齿槽转矩周期内预设的每个等分位置对应的辨识均值；在同步电机的旋转周期内计算多个辨识均值对应的判定值；判断判定值是否小于预判定阈值；如果是,基于辨识均值计算每个等分位置对应的齿槽转矩标定值。本申请能够利用伺服驱动器实现对齿槽转矩的精确标定,无需其他高精度伺服设备,且操作简单、成本较低。(The embodiment of the application provides a method and a device for calibrating cogging torque of a synchronous motor and electronic equipment, wherein a characteristic frequency multiplication value and a motor rotating speed of the synchronous motor are obtained under the condition that the synchronous motor runs at a low speed according to each rotating period; setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed; calculating an identification mean value corresponding to each preset equal division position in the cogging torque period based on a plurality of filter functions; calculating judgment values corresponding to a plurality of identification mean values in a rotation period of the synchronous motor; judging whether the judgment value is smaller than a predetermined threshold value; and if so, calculating a cogging torque calibration value corresponding to each equally divided position based on the identification mean value. The method and the device can utilize the servo driver to realize accurate calibration of the cogging torque, do not need other high-precision servo equipment, and are simple to operate and low in cost.)

1. A method for synchronous motor cogging torque calibration is characterized in that the method is used for a servo driver; the method comprises the following steps:

aiming at each rotation period, acquiring a characteristic frequency multiplication value and a motor rotating speed of a synchronous motor under the low-speed operation of the synchronous motor;

setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed;

calculating an identification mean value corresponding to each preset equal division position in a tooth space torque period based on the plurality of filter functions;

calculating a plurality of judgment values corresponding to the identification mean values in a rotation period of the synchronous motor;

judging whether the judgment value is smaller than a predetermined threshold value;

and if so, calculating a cogging torque calibration value corresponding to each equally divided position based on the identification mean value.

2. The method of claim 1, wherein the step of calculating the identification mean corresponding to each preset halving position in the cogging torque cycle based on a plurality of the filter functions comprises:

driving a rotating speed regulator in the servo driver to regulate the rotating speed of the motor to obtain a rotating speed set value;

filtering the rotating speed given value by utilizing a plurality of filtering functions to obtain a filtering value corresponding to each filtering function;

adding and calculating the filtering values corresponding to the filtering functions at each equally divided position to obtain an identification value corresponding to each equally divided position;

and carrying out mean value calculation on all the identification values corresponding to each equally divided position in the rotation period to obtain an identification mean value corresponding to each equally divided position.

3. The method according to claim 1, wherein the step of calculating a plurality of determination values corresponding to the recognition average value in a rotation cycle of the synchronous machine includes one of:

calculating the average value of the plurality of identification mean values to obtain a judgment value; alternatively, the first and second electrodes may be,

and carrying out root mean square calculation on the plurality of identification mean values to obtain a judgment value.

4. The method of claim 2, wherein calculating a cogging torque calibration for each of the equally divided positions based on the identified mean comprises:

aiming at each halving position, acquiring an initial cogging torque calibration value corresponding to the halving position in the last rotation period;

and adding the initial cogging torque calibration value and the identification mean value to obtain the cogging torque calibration value.

5. The method of claim 2, wherein after calculating a cogging torque calibration for each of the aliquot locations based on the identified mean, the method further comprises:

and storing the cogging torque calibration value corresponding to each halving position into a storage area of the servo driver.

6. The method of claim 5, wherein after storing the cogging torque calibration for each of the aliquot locations in a memory area of the servo drive, the method further comprises:

acquiring position information of a motor rotor fed back by an encoder of the synchronous motor in real time;

determining an equally divided position based on the position information;

searching a first cogging torque calibration value and a second cogging torque calibration value adjacent to the halving position from the storage area;

performing linear interpolation calculation on the first tooth socket torque calibration value and the second tooth socket torque calibration value to obtain a compensation value;

and calculating the motor current value corresponding to the equant position according to the compensation value.

7. The method of claim 6, wherein the step of calculating the motor current values corresponding to the equally divided positions based on the compensation values comprises:

and adding the compensation value corresponding to the equant position and the given value of the rotating speed for calculation to obtain the current value of the motor.

8. The method according to claim 6, wherein the motor current value is a current command value of a Q-axis of the motor.

9. The device for calibrating the cogging torque of the synchronous motor is characterized in that the device is used for a servo driver; the device comprises:

the acquisition module is used for acquiring a characteristic frequency multiplication value and a motor rotating speed of the synchronous motor under the low-speed operation of the synchronous motor aiming at each rotation period;

the setting module is used for setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed;

the first calculation module is used for calculating an identification mean value corresponding to each preset equal division position in a tooth space torque period based on a plurality of filter functions;

the second calculation module is used for calculating judgment values corresponding to the identification mean values in a rotation period of the synchronous motor;

the judging module is used for judging whether the judging value is smaller than a pre-judging threshold value or not;

and the third calculation module is used for calculating the cogging torque calibration value corresponding to each equally divided position based on the identification mean value if the judgment module judges that the result is yes.

10. An electronic device comprising a processor and a memory, the memory storing computer-executable instructions executable by the processor, the processor executing the computer-executable instructions to implement the method of any one of claims 1 to 8.

Technical Field

The invention relates to the technical field of motor control, in particular to a method and a device for calibrating cogging torque of a synchronous motor and electronic equipment.

Background

Cogging torque is an inherent phenomenon of a permanent magnet motor, and is torque generated in a circumferential direction by interaction of a permanent magnet field and cogging of an armature core when a motor winding is not energized. It is invariant, in relation to the rotor position. The cogging torque can cause the permanent magnet motor to generate vibration and noise during the operation, and the pulsating torque is transmitted to the load through the rotating shaft, so that the speed of the system and the accuracy of position control are reduced.

In order to reduce the influence of the cogging torque, the cogging torque is calibrated mainly by a lever measurement method and a torque meter method in the prior art, the lever measurement method is simple, the measurement precision is poor, the specific quantitative relation between the cogging torque and the position of a rotor cannot be reflected, and only the characteristic of the cogging torque can be roughly analyzed, so the method is mainly used for occasions with low precision requirements; the torquemeter method utilizes a high-precision servo system for calibration, although the method can accurately calibrate the cogging torque, high-precision equipment is required, the operation is complex, and the cost is high.

Disclosure of Invention

In view of this, the present invention aims to provide a method, an apparatus and an electronic device for calibrating cogging torque of a synchronous motor, which effectively overcome the defect of the conventional cogging torque calibration, realize accurate calibration of cogging torque by using a servo driver, do not need other high-precision servo devices, and have the advantages of simple operation and low cost.

In a first aspect, an embodiment of the present invention provides a method for calibrating cogging torque of a synchronous motor, where the method is used for a servo driver; the method comprises the following steps: aiming at each rotation period, acquiring a characteristic frequency multiplication value and a motor rotating speed of the synchronous motor under the low-speed operation of the synchronous motor; setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed; calculating an identification mean value corresponding to each preset equal division position in the cogging torque period based on a plurality of filter functions; calculating judgment values corresponding to a plurality of identification mean values in a rotation period of the synchronous motor; judging whether the judgment value is smaller than a predetermined threshold value; and if so, calculating a cogging torque calibration value corresponding to each equally divided position based on the identification mean value.

The step of calculating the identification mean value corresponding to each preset equal division position in the cogging torque period based on the plurality of filter functions includes: a rotating speed regulator in the servo driver is driven to regulate the rotating speed of the motor to obtain a rotating speed set value; filtering the rotating speed given value by utilizing a plurality of filtering functions to obtain a filtering value corresponding to each filtering function; adding and calculating the filtering values corresponding to the filtering functions at each equally divided position to obtain an identification value corresponding to each equally divided position; and carrying out mean value calculation on all the identification values corresponding to each equally divided position in a rotation period to obtain an identification mean value corresponding to each equally divided position.

The step of calculating the determination values corresponding to the plurality of identification means within the rotation period of the synchronous motor includes one of: calculating the mean values of the plurality of identification mean values to obtain a judgment value; or, performing root mean square calculation on the plurality of identification mean values to obtain a judgment value.

The step of calculating the cogging torque calibration value corresponding to each equally divided position based on the identification mean value includes: aiming at each equant position, acquiring an initial cogging torque calibration value corresponding to the equant position of the previous rotation period; and adding the initial cogging torque calibration value and the identification mean value to obtain the cogging torque calibration value.

After calculating the cogging torque calibration value corresponding to each of the equally divided positions based on the identified average value, the method further includes: and storing the cogging torque calibration value corresponding to each halving position into a storage area of the servo driver.

After storing the cogging torque calibration value corresponding to each halved position in the storage area of the servo driver, the method further comprises: acquiring position information of a motor rotor fed back by an encoder of the synchronous motor in real time; determining an equally divided position based on the position information; searching a first tooth space torque calibration value and a second tooth space torque calibration value which are adjacent to the equal division positions from the storage area; performing linear interpolation calculation on the first tooth socket torque calibration value and the second tooth socket torque calibration value to obtain a compensation value; and calculating the motor current value corresponding to the equally divided position according to the compensation value.

The step of calculating the motor current value corresponding to the equally divided position according to the compensation value includes: and adding the compensation value corresponding to the equant position and the given value of the rotating speed to calculate to obtain the current value of the motor.

The motor current value is a current command value of the Q axis of the motor.

In a second aspect, an embodiment of the present invention further provides a device for calibrating cogging torque of a synchronous motor, where the device is used for a servo driver; the above-mentioned device includes: the acquisition module is used for acquiring a characteristic frequency multiplication value and a motor rotating speed of the synchronous motor under the low-speed operation of the synchronous motor aiming at each rotation period; the setting module is used for setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed; the first calculation module is used for calculating an identification mean value corresponding to each preset equal division position in a tooth space torque period based on a plurality of filter functions; the second calculation module is used for calculating judgment values corresponding to the identification mean values in the rotation period of the synchronous motor; the judging module is used for judging whether the judging value is smaller than a pre-judging threshold value or not; and the third calculation module is used for calculating the cogging torque calibration value corresponding to each equally divided position based on the identification mean value if the judgment module judges that the cogging torque calibration value is positive.

In a third aspect, an embodiment of the present invention further provides an electronic device, where the electronic device includes a processor and a memory, where the memory stores computer-executable instructions that can be executed by the processor, and the processor executes the computer-executable instructions to implement the foregoing method.

In a fourth aspect, the embodiments of the present invention also provide a computer-readable storage medium, where the computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are called and executed by a processor, the computer-executable instructions cause the processor to implement the above-mentioned method.

The embodiment of the invention has the following beneficial effects:

the embodiment of the application provides a method and a device for calibrating cogging torque of a synchronous motor and electronic equipment, wherein a characteristic frequency multiplication value and a motor rotating speed of the synchronous motor are obtained under the condition that the synchronous motor runs at a low speed according to each rotating period; setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed; calculating an identification mean value corresponding to each preset equal division position in the cogging torque period based on a plurality of filter functions; calculating judgment values corresponding to a plurality of identification mean values in a rotation period of the synchronous motor; judging whether the judgment value is smaller than a predetermined threshold value; and if so, calculating a cogging torque calibration value corresponding to each equally divided position based on the identification mean value. The method and the device can utilize the servo driver to realize accurate calibration of the cogging torque, do not need other high-precision servo equipment, and are simple to operate and low in cost.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and drawings.

In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a flowchart of a method for calibrating cogging torque of a synchronous motor according to an embodiment of the present invention;

FIG. 2 is a block diagram of a rotational speed control loop of a servo system according to an embodiment of the present invention;

FIG. 3 is a flow chart of another method for calibrating cogging torque of a synchronous motor according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a device for calibrating cogging torque of a synchronous motor according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.

Detailed Description

To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Considering that the existing lever measuring method is simple, has poor measuring precision, cannot reflect the specific quantitative relation between the cogging torque and the rotor position, and only can roughly analyze the characteristics of the cogging torque, so the lever measuring method is mainly used for occasions with low precision requirements; the torquemeter method utilizes a high-precision servo system for calibration, although the method can accurately calibrate the cogging torque, high-precision equipment is required, the operation is complex, and the cost is high; based on the above, the method, the device and the electronic device for calibrating the cogging torque of the synchronous motor provided by the embodiment of the invention can realize accurate calibration of the cogging torque by using the servo driver, do not need other high-precision servo devices, and have the advantages of simple operation and low cost.

The embodiment provides a method for calibrating cogging torque of a synchronous motor, which is used for a servo driver, wherein a control part and a driving part of the servo motor are generally integrated in the industry and collectively referred to as the servo driver, the servo driver generally comprises an MCU (micro controller Unit) control Unit (generally, an MCU processor chip and an accessory circuit thereof) or other digital microprocessors, the driver is a power driving part, outputs current to the motor under the control of the MCU to drive the motor, the servo motor is generally a permanent magnet synchronous motor, a stepping motor, a dc brushless motor, and the like, and a motor shaft is provided with an encoder (an incremental encoder, an absolute magnetic encoder, or a rotary transformer) for detecting the shaft position of a motor rotor and measuring the speed of the motor. The servo drive can typically implement position control, speed control, and current (torque) control of the motor.

Referring to a flow chart of a method for calibrating cogging torque of a synchronous motor shown in fig. 1, the method specifically includes the following steps:

step S102, aiming at each rotation period, under the condition that the synchronous motor runs at a low speed, acquiring a characteristic frequency multiplication value and a motor rotating speed of the synchronous motor;

the rotation period refers to a mechanical period of 360 degrees of the rotor of the synchronous motor rotating for one circle, the servo driver controls the synchronous motor to rotate at a low speed and a uniform speed at a rated rotation speed not greater than 2% under the rotation period, and the characteristic frequency multiplication value and the motor rotation speed of the synchronous motor are obtained under the low-speed operation of the synchronous motor.

The characteristic frequency multiplication value is a cogging characteristic aiming at the cogging, wherein the cogging is periodic fluctuation related to the position of the rotor, the fluctuation frequency multiplication number of the rotor relative to the rotating speed is related to the number of the magnetic pole pairs of the rotor and the number of the slots of the stator, and the characteristic frequency multiplication value is defined as that the cogging characteristic generates Q periods of fluctuation when the rotor rotates for one circle; the Q value is not only generally unique, and k characteristic frequency multiplication values Q can be artificially set according to the multiple of the magnetic pole pair number P of the motor rotor, the multiple of the stator slot number W and the common multiple of the two numbers₀～Q_kOr obtaining the characteristic frequency multiplication value through self-identification.

The characteristic frequency multiplication value obtained by self-identification is as follows:

the servo driver drives the synchronous motor to run at a low speed for a certain time (generally, the motor is ensured to rotate for more than 5 circles), a rotating speed feedback value or a current feedback value of the synchronous motor is sampled and stored at a certain sampling rate (generally, more than 100 Hz), the stored data is subjected to fast Fourier analysis, and k characteristic frequency multiplication values Q with higher amplitude are determined by contrasting with the rotating speed RPM of the motor₀～Q_k(wherein Q)₀～Q_kThe number of the magnetic pole pairs P of the rotor of the synchronous motor, the number of the stator slots Z and the common multiple of the two numbers) are required.

Step S104, setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed;

according to the determined k characteristic frequency multiplication values (generally 3-5 according to the operational capability of the servo driver, the more the calibration effect is better) and the motor rotating speed, k band-pass/peak filter functions F0(s) -Fk(s) are set, wherein the center frequency of each filter function is as follows: Q0-Qk/2 pi/omega_mWherein, ω is_mIs the motor speed.

Step S106, calculating an identification mean value corresponding to each preset equal division position in the cogging torque period based on a plurality of filter functions;

the rotation period is divided equally according to the number N of the stator slots, each part occupies 360/N degrees and is called a cogging torque period, one cogging torque period is divided equally into M sections of positions according to the precision requirement to obtain the equal division positions, the greater the M value is, the higher the precision is, and the number of the equal division positions is not limited.

Calculating the identification mean value corresponding to each equally divided position can be realized through the steps A1-A4:

step A1, driving a rotating speed regulator in a servo driver to regulate the rotating speed of the motor to obtain a rotating speed set value;

usually, a rotation speed regulator in the servo driver is connected with an encoder of the synchronous motor to obtain the motor rotation speed of the synchronous motor, for easy understanding, fig. 2 shows a block diagram of a rotation speed control loop of the servo system, and it can be known from fig. 2 that the encoder obtains the rotor position θ of the synchronous motor_mThen, the servo driver can be based on the rotor position θ_mCalculating the motor speed omega of the synchronous motor_mAnd the motor rotation speed omega is adjusted_mFed back to a speed regulator, which regulates the speed omega of the motor_mAnd regulating to obtain a rotating speed set value.

Step A2, filtering the given rotating speed value by using a plurality of filter functions respectively to obtain a filter value corresponding to each filter function;

and respectively filtering the rotating speed set value output by the speed regulator through the set filtering functions F0(s) -Fk(s) to obtain filtering values corresponding to the filtering functions.

Step A3, adding filter values corresponding to the filter functions at each equally divided position to obtain an identification value corresponding to each equally divided position;

step a4, performing mean calculation on all the identification values corresponding to each equally divided position in the rotation period to obtain an identification mean corresponding to each equally divided position.

As shown in fig. 2, the filter values output by the filter functions are added to obtain an identification value h corresponding to each equal division position, all the identification values h obtained in the equal division position m of a single rotor in the same rotation period are averaged according to the equal division position m of the motor rotor to obtain an identification average value corresponding to the equal division position m, and the calculation process of the identification average values of the other position partitions is the same as above and is not repeated herein.

To facilitate data storage, two storage arrays C0[ N ] and C1[ N ] are provided in the servo drive, where C0 is used to store the cogging torque calibration and C1 is used to spool the identification average. After the identification mean value corresponding to the equal division position m is obtained, the identification mean value is assigned to the partition corresponding position C1[ m ] of the storage array C1 for storage.

Step S108, calculating judgment values corresponding to a plurality of identification mean values in a rotation period of the synchronous motor;

the decision value can be obtained by calculating the mean value of a plurality of identification mean values; alternatively, the determination value may be an average value obtained by averaging the recognition mean values in the storage array C1 or a root mean square value obtained by root mean square calculation of the recognition mean values, which is not limited herein.

Step S110, judging whether the judgment value is smaller than a predetermined threshold value;

the above process is an iterative convergence process, after each rotation period is finished (the rotor completes a complete rotation), the average value or the root mean square value of the storage array C1 is judged, when the judgment value is smaller than a set threshold value S (usually S is selected to be smaller than 5% of rated current), convergence is judged, step S112 is executed, the cogging torque calibration process is finished, otherwise, the operation is continued by returning to step S106.

And step S112, calculating a cogging torque calibration value corresponding to each equally divided position based on the identification mean value.

The above step S112 can be realized by the steps B1 to B2:

step B1, acquiring an initial cogging torque calibration value corresponding to the equant position of the previous rotation period aiming at each equant position;

and step B2, adding the initial cogging torque calibration value and the identification mean value to obtain the cogging torque calibration value.

Following the previous example, after obtaining the identification mean corresponding to the equal division positions m, the partition corresponding position C0[ m ] m of the storage array C0 is made]＝C0[m]_{On the upper part}+C1[m]And in the next rotation period of the rotor, when the rotor runs to the equal division position m, C0[ m [ ]]_{On the upper part}And adding the initial cogging torque calibration value as Iq command feedforward (namely the initial cogging torque calibration value) and the identification mean value of the equal division position m to obtain the cogging torque calibration value of the equal division position m, wherein the cogging torque calibration value is used as the current command value input of the motor Q shaft of the Iq current regulator of the servo driver at the final equal division position m.

As shown in fig. 2, the Iq current regulator is connected with the rotation speed regulator and is also connected with the synchronous motor through the pulse generator and the driving circuit so as to drive the synchronous motor to rotate under the current command value of the Q axis of the motor; the Id current regulator of the servo driver samples the driving current of the driving circuit and performs current regulation according to the driving current, and the current regulation is the same as the current regulation by the Id current regulator in the prior art, and is not described herein again.

The embodiment of the application provides a method for calibrating cogging torque of a synchronous motor, wherein a characteristic frequency multiplication value and a motor rotating speed of the synchronous motor are obtained under the condition that the synchronous motor runs at a low speed according to each rotating period; setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed; calculating an identification mean value corresponding to each preset equal division position in the cogging torque period based on a plurality of filter functions; calculating judgment values corresponding to a plurality of identification mean values in a rotation period of the synchronous motor; judging whether the judgment value is smaller than a predetermined threshold value; and if so, calculating a cogging torque calibration value corresponding to each equally divided position based on the identification mean value. The method and the device can utilize the servo driver to realize accurate calibration of the cogging torque, do not need other high-precision servo equipment, and are simple to operate and low in cost.

The embodiment provides another method for calibrating the cogging torque of the synchronous motor, which is realized on the basis of the embodiment; the present embodiment focuses on a specific implementation of cogging torque compensation. As shown in fig. 3, another flowchart of a method for calibrating cogging torque of a synchronous motor, the method for calibrating cogging torque of a synchronous motor in this embodiment includes the following steps:

step S302, aiming at each rotation period, under the condition that the synchronous motor runs at a low speed, acquiring a characteristic frequency multiplication value and a motor rotating speed of the synchronous motor;

step S304, setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed;

step S306, calculating an identification mean value corresponding to each preset equal division position in the cogging torque period based on a plurality of filter functions;

step S308, calculating judgment values corresponding to a plurality of identification mean values in the rotation period of the synchronous motor;

step S310, judging whether the judgment value is smaller than a predetermined threshold value;

if yes, go to step S312, if no, go to step S306.

Step S312, calculating a cogging torque calibration value corresponding to each equally divided position based on the identification mean value;

step S314, storing the cogging torque calibration value corresponding to each equant position in a storage area of a servo driver;

in specific implementation, the cogging torque calibration value stored in the storage data C0 is stored in an internal memory or an external memory of the servo driver MCU, and the cogging torque calibration is completed.

Step S316, acquiring the position information of the motor rotor fed back by the encoder of the synchronous motor in real time;

step S318, determining an equal division position based on the position information;

the position information is the rotor position θ obtained by the encoder in fig. 2_mThe servo driver can determine which of the divided positions corresponds to the position information based on the position information. For the sake of understanding, for example, a highway is divided into N equal segments, and a driver drives from one end to the other end, and then knows which segment is located according to the driving mileage information of the vehicle, wherein the mileage is the position information obtained by the encoder. Similarly, the process of determining the equal position of the position information is the same, and is not described in detail here.

Step S320, searching a first tooth space torque calibration value and a second tooth space torque calibration value which are adjacent to the equant positions from a storage area;

generally, the cogging torque calibration values and the halved positions are stored in the storage area in a one-to-one correspondence, after the halved position corresponding to the position information is determined in step S318, two halved positions adjacent to the halved position can be found in the storage area, and the cogging torque calibration values respectively corresponding to the two adjacent halved positions are determined as the first and second found cogging torque calibration values adjacent to the halved position.

Step S322, performing linear interpolation calculation on the first cogging torque calibration value and the second cogging torque calibration value to obtain a compensation value;

in step S324, a motor current value corresponding to the equal division position is calculated from the compensation value.

In this embodiment, the motor current value is a current command value (motor current value) of the Q axis of the motor, and the compensation value obtained in step S322 and the given value of the rotation speed are added to obtain a motor current value corresponding to the divided position, and the current compensation is performed on the synchronous motor by using the motor current value.

Corresponding to the method embodiment, the embodiment of the invention provides a synchronous motor cogging torque calibration device, wherein the device is used for a servo driver; fig. 4 shows a schematic structural diagram of a synchronous motor cogging torque calibration device, which, as shown in fig. 4, includes:

an obtaining module 402, configured to obtain, for each rotation period, a characteristic frequency multiplier and a motor rotation speed of the synchronous motor when the synchronous motor operates at a low speed;

a setting module 404, configured to set a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotation speed;

the first calculating module 406 is configured to calculate an identification mean value corresponding to each preset equal division position in the cogging torque period based on a plurality of filter functions;

the second calculating module 408 is configured to calculate a determination value corresponding to the plurality of identification mean values in a rotation period of the synchronous motor;

a judging module 410, configured to judge whether the judgment value is smaller than a predetermined threshold;

and a third calculating module 412, if the judging module judges that the result is yes, calculating a cogging torque calibration value corresponding to each equally divided position based on the identification mean value.

The embodiment of the application provides a synchronous motor cogging torque calibration device, wherein a characteristic frequency multiplication value and a motor rotating speed of a synchronous motor are obtained for each rotating period under the low-speed operation of the synchronous motor; setting a plurality of filter functions according to the characteristic frequency multiplication value and the motor rotating speed; calculating an identification mean value corresponding to each preset equal division position in the cogging torque period based on a plurality of filter functions; calculating judgment values corresponding to a plurality of identification mean values in a rotation period of the synchronous motor; judging whether the judgment value is smaller than a predetermined threshold value; and if so, calculating a cogging torque calibration value corresponding to each equally divided position based on the identification mean value. The method and the device can utilize the servo driver to realize accurate calibration of the cogging torque, do not need other high-precision servo equipment, and are simple to operate and low in cost.

The synchronous motor cogging torque calibration device provided by the embodiment of the invention has the same technical characteristics as the synchronous motor cogging torque calibration method provided by the embodiment, so that the same technical problems can be solved, and the same technical effects can be achieved.

The embodiment of the present application further provides an electronic device, as shown in fig. 5, which is a schematic structural diagram of the electronic device, where the electronic device includes a processor 121 and a memory 120, the memory 120 stores computer-executable instructions that can be executed by the processor 121, and the processor 121 executes the computer-executable instructions to implement the above method for calibrating cogging torque of a synchronous motor.

In the embodiment shown in fig. 5, the electronic device further comprises a bus 122 and a communication interface 123, wherein the processor 121, the communication interface 123 and the memory 120 are connected by the bus 122.

The memory 120 may include a high-speed Random Access Memory (RAM) and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory. The communication connection between the network element of the system and at least one other network element is realized through at least one communication interface 123 (which may be wired or wireless), and the internet, a wide area network, a local network, a metropolitan area network, and the like may be used. The bus 122 may be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, an EISA (Extended Industry Standard Architecture) bus, or the like. The bus 122 may be divided into an address bus, a data bus, a control bus, and the like. For ease of illustration, only one double-headed arrow is shown in FIG. 5, but this does not indicate only one bus or one type of bus.

The processor 121 may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the above method may be performed by integrated logic circuits of hardware or instructions in the form of software in the processor 121. The Processor 121 may be a general-purpose Processor, and includes a Central Processing Unit (CPU), a Network Processor (NP), and the like; the device can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, a discrete Gate or transistor logic device, or a discrete hardware component. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in a memory, and the processor 121 reads information in the memory and completes the steps of the method for calibrating the cogging torque of the synchronous motor of the foregoing embodiment in combination with hardware thereof.

The embodiment of the present application further provides a computer-readable storage medium, where the computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are called and executed by a processor, the computer-executable instructions cause the processor to implement the method for calibrating cogging torque of a synchronous motor, where specific implementation may refer to the foregoing method embodiment, and details are not repeated herein.

The method and the device for calibrating cogging torque of a synchronous motor and the computer program product of the electronic device provided by the embodiments of the present application include a computer-readable storage medium storing program codes, where instructions included in the program codes may be used to execute the method described in the foregoing method embodiments, and specific implementation may refer to the method embodiments, and will not be described herein again.

Unless specifically stated otherwise, the relative steps, numerical expressions, and values of the components and steps set forth in these embodiments do not limit the scope of the present application.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a non-volatile computer-readable storage medium executable by a processor. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Finally, it should be noted that: the above-mentioned embodiments are only specific embodiments of the present application, and are used for illustrating the technical solutions of the present application, but not limiting the same, and the scope of the present application is not limited thereto, and although the present application is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: any person skilled in the art can modify or easily conceive the technical solutions described in the foregoing embodiments or equivalent substitutes for some technical features within the technical scope disclosed in the present application; such modifications, changes or substitutions do not depart from the spirit and scope of the exemplary embodiments of the present application, and are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.