阅读说明：本技术 电机调速方法及系统 (Motor speed regulation method and system ) 是由 王晓蕾 涂金生 王传傲 王振兴 徐彦 朱毅 于 2019-03-20 设计创作，主要内容包括：电机调速方法及系统,包括：获取直流电机的转速参考数据；获取预设调速阈值并与转速参考数据比较,据以判断转速值是否大于预设调速阈值；若是,则判定电机调速系统处于常速模式；若否,则判定电机调速系统处于低速模式；根据调速模式信息获取调速控制信息；根据调速控制信息,调节直流电机的转速与转速参考数据一致。本发明解决了现有技术存在调速效率低及效果差的技术问题。(The motor speed regulating method and system includes: acquiring rotating speed reference data of the direct current motor; acquiring a preset speed regulation threshold value, comparing the preset speed regulation threshold value with the rotating speed reference data, and judging whether the rotating speed value is greater than the preset speed regulation threshold value or not; if yes, judging that the motor speed regulating system is in a constant speed mode; if not, judging that the motor speed regulating system is in a low-speed mode; acquiring speed regulation control information according to the speed regulation mode information; and according to the speed regulation control information, regulating the rotating speed of the direct current motor to be consistent with the rotating speed reference data. The invention solves the technical problems of low speed regulation efficiency and poor effect in the prior art.)

1. A motor speed regulation method is characterized by comprising the following steps:

acquiring rotating speed reference data of the direct current motor;

acquiring a preset speed regulation threshold value, comparing the preset speed regulation threshold value with the rotating speed reference data, and judging whether the rotating speed value is greater than the preset speed regulation threshold value or not;

if so, judging that the motor speed regulating system is in a constant speed mode;

if not, the motor speed regulating system is judged to be in a low-speed mode

Acquiring speed regulation control information according to the speed regulation mode information;

and adjusting the rotating speed of the direct current motor to be consistent with the rotating speed reference data according to the speed regulation control information.

2. The method of claim 1, wherein the obtaining throttle control information comprises:

extracting a mode judgment result in the speed regulation mode information;

if the motor speed regulating system is in the constant speed mode, acquiring proportional integral derivative data of the direct current motor;

calculating a constant speed regulating signal according to the proportional integral derivative data;

if the motor speed regulating system is in the low-speed mode, acquiring micro-stepping current data of the direct current motor;

and calculating a low-speed regulating signal according to the micro-stepping current data.

3. The method of claim 2, wherein said obtaining micro-step data comprises:

calculating torque data T according to the following formula_m：

T_m＝K_tI_msin(θ_tm)

Wherein I_mIs torque current, θ_tmIs a torque angle, K_tIs the torque gain;

calculating angle reference data according to the rotating speed reference data;

calculating reference current data according to the angle reference data;

calculating the micro-step data according to the reference current data;

adjusting the torque data T based on the microstepping data_m。

4. The method of claim 1, wherein the step of extracting the coupled-in signal comprises:

extracting a reference speed in the rotational speed reference data

Calculating the angle reference data according to the following formula

Wherein, P_nThe number of pole pairs of the motor is shown.

5. The method of claim 1, wherein the step of resonantly processing the signal comprises:

obtaining torque angle data theta of direct current motor_tm；

Calculating the reference current data according to the following formula

Wherein, K_ptcThe gain is controlled stepwise.

6. A motor speed regulation system, comprising:

the reference module is used for acquiring rotating speed reference data of the direct current motor;

the rotating speed judging module is used for acquiring a preset speed regulating threshold value, comparing the preset speed regulating threshold value with the rotating speed reference data and judging whether the rotating speed value is greater than the preset speed regulating threshold value or not;

the constant speed judging module is used for judging that the motor speed regulating system is in a constant speed mode when the rotating speed value is greater than the preset speed regulating threshold value;

the low-speed judging module is used for judging that the motor speed regulating system is in a low-speed mode when the rotating speed value is less than or equal to the preset speed regulating threshold value;

the control information acquisition module is used for acquiring speed regulation control information according to the speed regulation mode information;

and the speed regulating module is used for regulating the rotating speed of the direct current motor to be consistent with the rotating speed reference data according to the speed regulating control information.

7. The system of claim 6, wherein the control information obtaining module comprises:

the mode acquisition module is used for extracting a mode judgment result in the speed regulation mode information;

the constant-speed motor data module is used for acquiring proportional integral derivative data of the direct-current motor when the motor speed regulating system is in the constant-speed mode;

the constant speed regulating signal module is used for calculating a constant speed regulating signal according to the proportional-integral-derivative data;

the low-speed motor data module is used for acquiring micro-stepping current data of the direct current motor when the motor speed regulating system is in the low-speed mode;

and the low-speed regulating signal module is used for calculating a low-speed regulating signal according to the micro-stepping current data.

8. The system of claim 7, wherein the low speed motor data module comprises:

a torque data module to calculate torque data T according to the following equation_m：

T_m＝K_tI_msin(θ_tm)

Wherein I_mIs torque current, θ_tmIs a torque angle, K_tIs the torque gain;

the angle reference data module is used for calculating angle reference data according to the rotating speed reference data;

the current reference data module is used for calculating reference current data according to the angle reference data;

the micro-stepping module is used for calculating the micro-stepping data according to the reference current data;

a torque adjusting module for adjusting the torque data T according to the micro-step data_m。

9. The system of claim 7, wherein the angular reference data module comprises:

a reference data extraction module for extracting the reference speed in the rotating speed reference data

An angle reference calculation module for calculating the angle reference data according to the following formula

Wherein, P_nThe number of pole pairs of the motor is shown.

10. The system of claim 9, wherein the current reference data module comprises:

a torque angle module for acquiring torque angle data theta of the DC motor_tm；

A reference current module to calculate the reference current data according to the following formula:

wherein, K_ptcThe gain is controlled stepwise.

Technical Field

The invention relates to a mechanical fault signal detection method, in particular to a motor speed regulation method and a motor speed regulation system.

Background

Brushless dc motors are used in a wide variety of applications, such as automotive, tool, industrial control, automation, and aerospace. The speed and torque control of the brushless dc motor can be achieved by means of hall sensor signals and phase currents, but the speed control of the brushless dc motor is mainly used for medium and high speeds, because the hall sensors can only determine the rotor position at fixed angular intervals (60 °). However, in some specific environments, a motor is required to achieve a low rotation speed, for example, a blood pump of an artificial heart needs a low rotation speed of the motor to drive, so that when the motor is provided with a high-resolution encoder, accurate control at a low speed can be achieved, but the cost is too large to be suitable for various traditional industries. Therefore, how to realize low-speed regulation of the brushless motor at low cost becomes one of important research directions in the field of motor application.

In summary, the fault signal enhancement method in the prior art has the technical problems of poor speed regulation effect and low precision.

Disclosure of Invention

In view of the technical problems of poor speed regulation effect and low precision of the fault signal enhancement method in the prior art, the invention aims to provide a motor speed regulation method and a motor speed regulation system, wherein the motor speed regulation method comprises the following steps: acquiring rotating speed reference data of the direct current motor; acquiring a preset speed regulation threshold value, comparing the preset speed regulation threshold value with the rotating speed reference data, and judging whether the rotating speed value is greater than the preset speed regulation threshold value or not; if yes, judging that the motor speed regulating system is in a constant speed mode; if not, judging that the motor speed regulating system is in a low-speed mode; acquiring speed regulation control information according to the speed regulation mode information; and according to the speed regulation control information, regulating the rotating speed of the direct current motor to be consistent with the rotating speed reference data.

In an embodiment of the present invention, the acquiring the speed control information includes: extracting a mode judgment result in the speed regulation mode information; if the motor speed regulating system is in a constant speed mode, acquiring proportional integral differential data of the direct current motor; calculating a constant speed regulating signal according to the proportional integral derivative data; if the motor speed regulating system is in a low-speed mode, acquiring micro-stepping current data of the direct current motor; and calculating a low-speed regulating signal according to the micro-stepping current data.

In one embodiment of the present invention, acquiring micro-step data includes: calculating torque data T according to the following formula_m：

T_m＝K_tI_msin(θ_tm)

Wherein I_mIs torque current, θ_tmIs a torque angle, K_tIs the torque gain; calculating angle reference data according to the rotating speed reference data; calculating reference current data according to the angle reference data; calculating micro-step data according to the reference current data; the torque data is adjusted based on the micro-step data.

In an embodiment of the present invention, the step of calculating the angle reference data includes: extracting reference speeds from rotational speed reference dataCalculating the angle reference data according to the following formula

Wherein, P_nThe number of pole pairs of the motor is shown.

In one embodiment of the present invention, the step of calculating the reference current includes: obtaining torque angle data theta of direct current motor_tm(ii) a Calculating reference current data according to the following formula

Wherein, K_ptcThe gain is controlled stepwise.

In one embodiment of the present invention, a motor speed control system includes: the reference module is used for acquiring rotating speed reference data of the direct current motor; the rotating speed judging module is used for acquiring a preset speed regulating threshold value, comparing the preset speed regulating threshold value with rotating speed reference data and judging whether the rotating speed value is greater than the preset speed regulating threshold value or not according to the rotating speed reference data, and the rotating speed judging module is connected with the reference module; the constant speed judging module is used for judging that the motor speed regulating system is in a constant speed mode when the rotating speed value is greater than a preset speed regulating threshold value, and the constant speed judging module is connected with the rotating speed judging module; the low-speed judging module is used for judging that the motor speed regulating system is in a low-speed mode when the rotating speed value is less than or equal to a preset speed regulating threshold value, and the low-speed judging module is connected with the rotating speed judging module; the control information acquisition module is used for acquiring speed regulation control information according to the speed regulation mode information, and is connected with the constant speed judgment module and the low speed judgment module; and the speed regulating module is used for regulating the rotating speed of the direct current motor to be consistent with the rotating speed reference data according to the speed regulating control information and is connected with the control information acquisition module.

In an embodiment of the present invention, the control information obtaining module includes: the mode acquisition module is used for extracting a mode judgment result in the speed regulation mode information; the constant speed motor data module is used for acquiring the proportional integral derivative data of the direct current motor when the motor speed regulating system is in a constant speed mode, and the constant speed motor data module is connected with the mode acquisition module; the constant speed regulating signal module is used for calculating a constant speed regulating signal according to the proportional-integral-derivative data and is connected with the constant speed motor data module; the low-speed motor data module is used for acquiring micro-stepping current data of the direct current motor when the motor speed regulating system is in a low-speed mode, and the low-speed motor data module is connected with the mode acquisition module; and the low-speed regulating signal module is used for calculating a low-speed regulating signal according to the micro-stepping current data, and is connected with the low-speed motor data module.

In one embodiment of the present invention, a low-speed motor data module includes: a torque data module to calculate torque data T according to the following equation_m：

T_m＝K_tI_msin(θ_tm)

Wherein I_mIs torque current, θ_tmIs a torque angle, K_tIs the torque gain; the angle reference data module is used for calculating angle reference data according to the rotating speed reference data; the current reference data module is used for calculating reference current data according to the angle reference data and is connected with the angle reference data module; the micro-stepping module is used for calculating micro-stepping data according to the torque data and the reference current data, and is connected with the torque data module and the reference current data module; a torque adjusting module for adjusting the torque data T according to the micro-step data_mAnd the torque adjusting module is connected with the micro-stepping module.

In an embodiment of the present invention, the angle reference data module includes: a reference data extraction module for extracting reference speed from the speed reference dataAn angle reference calculation module for calculating angle reference data according to the following formula

Wherein, P_nThe angle reference calculation module is connected with the reference data extraction module for the number of pole pairs of the motor.

In one embodiment of the present invention, the current reference data module includes: a torque angle module for acquiring torque angle data theta of the DC motor_tm(ii) a A current data module to calculate reference current data according to the following formula:

wherein, K_ptcThe current data module is connected to the torque angle module for step control gain.

As described above, the motor speed regulating method and system provided by the invention have the following beneficial effects: the invention enables the torque angle to have fixed change by changing the reference torque current, can effectively realize accurate speed regulation on the motor at low rotating speed without a high-resolution encoder, has high speed regulation efficiency and greatly reduces the production cost of the motor. The low-speed motor is applied in the oil field exploitation process, the system efficiency of the pumping well can be effectively improved, the energy consumption and equipment loss of the pumping well are reduced, and in addition, the low-speed motor is also widely applied to the aspects of medical machinery, food machinery, transportation and the like.

In summary, the invention provides a motor speed regulation method and system, which solve the technical problems of poor signal processing effect and low detection precision of weak fault signals in the prior art.

Drawings

Fig. 1 is a schematic diagram showing the steps of the motor speed regulating method of the present invention.

Fig. 2 is a schematic diagram of the motor data processing of the present invention.

FIG. 3 is a schematic diagram illustrating the step S5 in FIG. 1 according to an embodiment.

FIG. 4 is a diagram illustrating a step S54 in FIG. 3 according to an embodiment.

Fig. 5 is a diagram showing the angle current variation of the motor according to the present invention.

Fig. 6 is a schematic diagram illustrating the step S542 in fig. 4 in an embodiment.

Fig. 7 is a schematic diagram illustrating the step S543 in fig. 4 in an embodiment.

Fig. 8 is a schematic diagram of a motor speed regulation system module according to the present invention.

Fig. 9 is a block diagram of the control information obtaining module in fig. 8 according to an embodiment.

FIG. 10 is a block diagram of the low speed motor data block of FIG. 9 in one embodiment.

FIG. 11 is a block diagram of the angle reference data block of FIG. 10 in one embodiment.

FIG. 12 is a block diagram of the current reference data block of FIG. 10 according to one embodiment.

Description of the element reference numerals

1 reference module

2 rotating speed judging module

3 constant speed judging module

4 low-speed judging module

5 control information acquisition module

6 speed regulation module

51 mode acquisition module

52 constant speed motor data module

53 constant speed regulation signal module

54 low-speed motor data module

55 low speed regulating signal module

541 torque data module

542 Angle reference data Module

543 Current reference data Module

544 micro-stepping module

545 torque adjustment module

5421 reference data extraction Module

5422 angular reference calculation Module

5431 Torque Angle Module

5432 Current data Module

Description of step designations

Method steps S1-S6

Method steps S51-S55

Method steps S541-S545

Method steps S5421-S5422

Method steps S5431-S5432

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure.

Referring to fig. 1 to 12, it should be understood that the structures shown in the drawings are only used for understanding and reading the present disclosure, and are not used to limit the conditions of the present invention, which can be implemented, so that the present invention has no technical significance, and any structural modification, ratio change or size adjustment should still fall within the scope of the present invention without affecting the efficacy and attainment of the present invention. In addition, the terms "upper", "lower", "left", "right", "middle" and "one" used in the present specification are for clarity of description, and are not intended to limit the scope of the present invention, and the relative relationship between the terms and the terms is not to be construed as a scope of the present invention.

Referring to fig. 1 and fig. 2, a schematic diagram of steps of a motor speed regulating method and a schematic diagram of motor data processing according to the present invention are shown, as shown in fig. 1 and fig. 2, an object of the present invention is to provide a motor speed regulating method and system, the motor speed regulating method includes:

s1, acquiring the rotation speed reference data of the DC motor, starting the power supply and inputting the reference rotation speed in one embodiment

S2, obtaining a preset speed-regulating threshold and comparing the preset speed-regulating threshold with the reference speed data to judge whether the speed value is greater than the preset speed-regulating threshold, wherein in one embodiment, the reference speed of the motor is judgedWhether the speed is greater than the threshold speed omega of normal speed regulation and control_A(A motor of 12 stages or more, for example, 400 rpm or less is called a low-speed motor, and ω can be set, for example_A400 rpm);

s3, if yes, the speed regulating system of the motor is judged to be in a constant speed mode, and in one embodiment, the reference rotating speed of the motor is determinedWith a threshold speed omega_ASwitching the speed regulation mode according to the size of the speed regulation mode;

s4, if not, determining that the motor speed regulating system is in a low-speed mode, in one embodiment, changing the reference torque current to enable the torque angle to have fixed change, utilizing a PID (proportional Integral Derivative) regulation control method micro-stepping current control method to regulate and control the speed of the motor, observing the real-time speed of the motor until the reference rotating speed is reached, and finishing speed regulation after the motor reaches a stable state;

s5, acquiring speed regulation control information according to the speed regulation mode information, in one embodiment, carrying out speed regulation and control on the motor by using a micro-stepping current control method, observing the real-time speed of the motor until the real-time speed reaches a reference rotating speed, and finishing speed regulation after the real-time speed reaches a stable speed;

and S6, according to the speed regulation control information, regulating the rotating speed of the direct current motor to be consistent with the rotating speed reference data, and in one embodiment, effectively realizing accurate speed regulation on the motor at low rotating speed without a high-resolution encoder.

In these embodiments, the rotation speed ω_AOther values, such as 300 or 500 rpm, may also be used.

Referring to fig. 3, which is a schematic diagram illustrating a step of step S5 in fig. 1 according to an embodiment, as shown in fig. 3, the step S5 of obtaining speed control information includes:

s51, extracting a mode judgment result in the speed regulation mode information, wherein in one embodiment, the reference speed output by the speed setting module is compared with the threshold speed;

s52, if the motor speed regulating system is in the constant speed mode, obtaining the proportional integral derivative data of the direct current motor, in one embodiment, if the reference speed is greater than the threshold speed, adopting PID speed modulation, and if the reference speed is less than the threshold voltage, adopting micro-stepping current regulation;

and S53, calculating a constant speed regulating signal according to the proportional integral derivative data, wherein in one embodiment, the module performs current control through the difference value of the real-time speed and the reference speed of the motor. The difference values are subjected to derivation, integration and multiple multiplication respectively, and the control of the motor current is realized through coefficients with different specific gravities, so that the modulation of the motor speed is realized. The module is realized by using FPGA and over-writing related codes;

s54, if the motor speed regulation system is in a low-speed mode, acquiring micro-stepping current data of the direct current motor, in one embodiment, using an FPGA to write related codes to realize the micro-stepping current data, wherein the module is used for measuring the rotating speed of the motor, a software measuring method is used for realizing the micro-stepping current data, and the FPGA is used for driving the brushless direct current electrode;

and S55, calculating a low-speed regulation signal according to the micro-stepping current data, in one embodiment, using FPGA and over-writing related codes to realize the low-speed regulation signal, generating sine waves, using the FPGA and over-writing related codes to realize the low-speed regulation signal, arranging a Hall filtering module to increase the stability and accuracy of the system, and using the FPGA and the over-writing related codes to realize the low-speed regulation signal.

Referring to fig. 4 and 5, which are a schematic diagram of the step of step S54 in fig. 3 in an embodiment and a relationship diagram of the change of the angle and the current of the motor, as shown in fig. 4 and 5, the step S54 of acquiring micro-step data includes:

s541, calculating torque data T according to the following formula_m：

T_m＝K_tI_msin(θ_tm)

Wherein I_mIs torque current, θ_tmIs a torque angle, K_tFor torque gain, in one embodiment, the motor torque is determined by the torque current and the torque angle;

s542, calculating angle reference data according to the rotating speed reference data, wherein in one embodiment, the maximum output torque is limited by the magnitude of a current vector, and the torque current amplitude is controlled by a torque angle, a reference speed and a reference rotating angle;

s543, calculating reference current data according to the angle reference data, wherein in one embodiment, the rotation angle of the phase current is determined by the motor reference speed, and the motor torque is automatically changed by the torque angle of the motor according to the load change;

s544, calculating micro-step data according to the reference current data, in an embodiment, feedback control using hall sensor signals is insufficient in a low speed range, and the motor speed may be controlled by a torque angle and a torque current of the motor;

and S545, adjusting the torque data according to the micro-stepping data, and in one embodiment, adjusting and controlling the rotating speed of the motor by changing the torque of the motor.

Referring to fig. 6, which is a schematic diagram illustrating a step of step S542 in fig. 4 in an embodiment, as shown in fig. 6, the step of calculating the angle reference data of step S542 includes:

s5421, extracting reference speed in rotating speed reference dataIn one embodiment, the actual torque of the motor is defined by the rotating current vector im (k) and the actual rotor vectorCurrent flow and torque angle theta between_tm(k)Is determined. When the actual current flows fromIs rotated toThe actual rotor position may be changed by the load torque;

s5422, calculating angle reference data according to the following formula

Wherein, P_nFor the motor pole pair number, in one embodiment, the torque current angle changes the reference angle in αβ rotating surfaces according to a fixed reference speed.

Referring to fig. 7, which is a schematic view of step S543 in fig. 4 in an embodiment, as shown in fig. 7, step S543 of calculating a reference current includes:

s5431, torque angle data theta of the direct current motor is obtained_tmIn one embodiment, if the load torque is lower than the previous step, then moving the actual rotor position moves to θ_r(k)To reduce the torque angle. Otherwise, make the torque angle theta_tm(k-1)Higher than the previous torque angle to increase output torque;

s5432, calculating reference current data according to the following formula

Wherein, K_ptcTo control the gain step by step, in one embodiment, when the gain K is greater than the threshold_ptcWhen the rated current of the motor is set, the maximum possible load is the rated output torque of the motor. Reference currentLimited by the maximum value of the protected motor and drive and the minimum value of the improved sudden load characteristic.

Referring to fig. 8, a schematic diagram of a motor speed regulating system module according to the present invention is shown, and as shown in fig. 8, a motor speed regulating system includes: the control system comprises a reference module 1, a rotating speed judging module 2, a constant speed judging module 3, a low speed judging module 4, a control information obtaining module 5 and a speed regulating module 6, wherein the reference module 1 is used for obtaining rotating speed reference data of a direct current motor; the rotating speed judging module 2 is used for acquiring a preset speed regulating threshold value, comparing the preset speed regulating threshold value with rotating speed reference data, and judging whether the rotating speed value is larger than the preset speed regulating threshold value or not according to the comparing result, and the rotating speed judging module 2 is connected with the reference module 1. The module is realized by using FPGA and over-writing related codes; the constant speed judging module 3 is configured to judge that the motor speed regulating system is in a constant speed mode when the rotating speed value is greater than a preset speed regulating threshold, and the constant speed judging module 3 is connected to the rotating speed judging module 2. The difference values are subjected to derivation, integration and multiple multiplication respectively, and the control of the motor current is realized through coefficients with different specific gravities, so that the modulation of the motor speed is realized. The module is realized by using FPGA and over-writing related codes; the low-speed judging module 4 is used for judging that the motor speed regulating system is in a low-speed mode when the rotating speed value is less than or equal to a preset speed regulating threshold value, and the low-speed judging module 4 is connected with the rotating speed judging module 2; the control information obtaining module 5 is configured to obtain speed regulation control information according to the speed regulation mode information, the control information obtaining module 5 is connected to the normal speed determining module 3, and the control information obtaining module 5 is connected to the low speed determining module 4, and in an embodiment, the module converts a binary system used into a 10-ary system for representation. The module is realized by using an FPGA and programming related codes and is used for displaying an input reference speed, an input threshold speed and a real-time rotating speed of a motor. The module is realized by accessing a peripheral with 12 nixie tubes and 8 keys to a development board; the speed regulation module 6 is used for regulating the rotating speed of the direct current motor to be consistent with the rotating speed reference data according to the speed regulation control information, the speed regulation module 6 is connected with the control information acquisition module 5, and in one embodiment, the module controls the current by processing the reference speed and processing the processed value of the signal obtained by the hall sensor again, so that the modulation of the rotating speed of the motor is realized.

Referring to fig. 9, which is a block diagram of the control information obtaining module in fig. 8 according to an embodiment, as shown in fig. 9, the control information obtaining module 5 includes: the system comprises a mode acquisition module 51, a constant-speed motor data module 52, a constant-speed regulation signal module 53, a low-speed motor data module 54 and a low-speed regulation signal module 55, wherein the mode acquisition module 51 is used for extracting a mode judgment result in speed regulation mode information; the constant speed motor data module 52 is used for acquiring proportional integral derivative data of the direct current motor when the motor speed regulating system is in a constant speed mode, and the constant speed motor data module 52 is connected with the mode acquisition module 51; a constant speed regulating signal module 53, which is used for calculating a constant speed regulating signal according to the proportional integral derivative data, wherein the constant speed regulating signal module 53 is connected with the constant speed motor data module 52; a low-speed motor data module 54, configured to obtain micro-step current data of the dc motor when the motor speed control system is in the low-speed mode, where the low-speed motor data module 54 is connected to the mode obtaining module 51; and the low-speed regulating signal module 55 is used for calculating a low-speed regulating signal according to the micro-stepping current data, and the low-speed regulating signal module 55 is connected with the low-speed motor data module 54.

Referring to fig. 10, which is a block diagram of the low-speed motor data module in fig. 9 according to an embodiment, as shown in fig. 10, the low-speed motor data module 54 includes: a torque data module 541, an angle reference data module 542, a current reference data module 543, a micro-step module 544, a torque adjustment module 545, the torque data module 541 configured to calculate torque data T according to the following equation_m：

T_m＝K_tI_msin(θ_tm)

Wherein I_mIs torque current, θ_tmIs a torque angle, K_tIs the torque gain; an angle reference data module 542 configured to calculate angle reference data according to the rotational speed reference data; a current reference data module 543 for calculating reference current data according to the angle reference data, wherein the current reference data module 543 is connected to the angle reference data module 542; micro-stepping module 544 to calculate a reference current based on the torque data and the reference current dataMicro-step data is obtained, and the micro-step module 544 is connected with the current reference data module 543; a torque adjustment module 545 to adjust the torque data T based on the micro-step data_mThe torque adjustment module 545 is coupled to the micro-step module 544.

Referring to fig. 11, which is a block diagram illustrating an embodiment of the angle reference data module of fig. 10, as shown in fig. 11, the angle reference data module 542 includes: a reference data extraction module 5421, an angle reference calculation module 5422, and a reference data extraction module 5421 for extracting a reference speed from the rotational speed reference dataAn angle reference calculation module 5422 for calculating angle reference data according to the following formula

Wherein, P_nThe angle reference calculation module 5422 is connected to the reference data extraction module 5421 for the number of pole pairs of the motor.

Referring to fig. 12, which is a block diagram of the current reference data block of fig. 10 in an embodiment, as shown in fig. 12, the current reference data block 543 includes: a torque angle module 5431 and a current data module 5432, the torque angle module 5431 to obtain torque angle data θ for the DC motor_tm(ii) a A current data module 5432 to calculate reference current data according to the following equation:

wherein, K_ptcThe current data module 5432 interfaces with the torque angle module 5431 for step control gain.

In summary, according to the speed regulating method and system for the motor provided by the invention, the reference torque current is changed to enable the torque angle to have fixed change, the motor can be effectively and accurately regulated at low rotating speed without a high-resolution encoder, the speed regulating efficiency is high, and the production cost of the motor is greatly reduced. The low-speed motor can be applied to effectively improve the efficiency of a pumping well system and reduce the energy consumption, equipment loss and the like of the pumping well in the process of oil field exploitation, and in addition, the low-speed motor is widely applied to aspects of medical machinery, food machinery, transportation and the like, has better application prospect, solves the technical problem of poor speed regulation effect and low precision in the prior art, and has very high commercial value and practicability.