阅读说明：本技术 一种永磁同步电机控制方法及其控制系统 (Permanent magnet synchronous motor control method and control system thereof ) 是由 邹腊年 徐飞飞 刘博� 于 2019-12-20 设计创作，主要内容包括：本发明公开一种永磁同步电机控制方法,包括：S1、启动电机,直至电机转速稳定；S2、校准位置传感器和电流传感器,使二者的延迟时间一致；S3、位置传感器实时检测电机内转子位置,电流传感器实时检测电机内线圈中的电流；S4、记录感应头正对色标的时刻t1,记录线圈中电流达到峰值时刻t2,并得出t1和t2的差值Δt；S5、判断Δt是否小于预定值,若Δt小于预定值则结束控制,若Δt大于预定值,则进行S6；S6、改变电源适配器供电的相位；S7、重复S2至S4,直至Δt小于预定值,进而结束控制。检测线圈正交切割磁感线的时刻与电流峰值时刻间的差值,改变供电相位,使二者差值减小到预定值,解决现有技术中永磁同步电机中电流与磁场不匹配的技术问题。(The invention discloses a permanent magnet synchronous motor control method, which comprises the following steps: s1, starting the motor until the rotating speed of the motor is stable; s2, calibrating the position sensor and the current sensor to make the delay time of the position sensor and the current sensor consistent; s3, detecting the position of the rotor in the motor in real time by a position sensor, and detecting the current in the coil in the motor in real time by a current sensor; s4, recording the time t1 when the induction head faces the color scale, recording the time t2 when the current in the coil reaches the peak value, and obtaining the difference value delta t between t1 and t 2; s5, judging whether the delta t is smaller than a preset value, if the delta t is smaller than the preset value, ending the control, and if the delta t is larger than the preset value, carrying out S6; s6, changing the phase of the power supply of the power adapter; and S7, repeating S2 to S4 until the delta t is smaller than the preset value, and then ending the control. The difference between the moment when the detection coil orthogonally cuts the magnetic induction line and the current peak value moment changes the power supply phase, so that the difference between the two is reduced to a preset value, and the technical problem that the current and the magnetic field in the permanent magnet synchronous motor in the prior art are not matched is solved.)

1. A permanent magnet synchronous motor control method is characterized by comprising the following steps:

s1, starting the motor until the rotating speed of the motor is stable;

s2, calibrating the position sensor and the current sensor to make the delay time of the position sensor and the current sensor consistent;

s3, detecting the position of the rotor in the motor in real time by a position sensor, and detecting the current in the coil in the motor in real time by a current sensor;

s4, recording the time t1 when the induction head faces the color scale, recording the time t2 when the current in the coil reaches the peak value, and obtaining the difference value delta t between t1 and t 2;

s5, judging whether the delta t is smaller than a preset value, if the delta t is smaller than the preset value, ending the control, and if the delta t is larger than the preset value, carrying out S6;

s6, changing the phase of the power supply of the power adapter;

and S7, repeating S2 to S4 until the delta t is smaller than the preset value, and then ending the control.

2. The permanent magnet synchronous motor control method according to claim 1, wherein the step S2 includes:

s21, detecting the output torque M0 of the motor after delta t is smaller than a preset value by a torque sensor;

s22, changing the power supply phase of the power adapter, and measuring the output torque M1 of the motor after the output torque of the motor is stable;

s23, repeating S2, continuously changing the power supply phase until the phase is changed for a period, and sequentially obtaining a torque M2 to a torque Mn;

s24, obtaining a maximum value Mmax from M1 to Mn, if M0 is larger than Mmax, the sensor delay does not need to be calibrated, and if M0 is smaller than Mmax, the phase difference between the phase corresponding to Mmax and the phase corresponding to M0 is the delay difference ξ between the position sensor and the current sensor;

and S25, delaying the feedback signal of the position sensor ξ, checking whether the delta t is smaller than a preset value, finishing calibration if the delta t is smaller than the preset value, and delaying the feedback signal of the current sensor by 2 ξ to finish calibration if the delta t is larger than the preset value.

3. The permanent magnet synchronous motor control method according to claim 1, wherein the predetermined value is 0.2 ms.

4. A permanent magnet synchronous motor control system based on the permanent magnet motor control method according to any one of claims 1 to 3, characterized by comprising: the controller is respectively connected with the position sensor, the current sensor and the power adapter, the motor is respectively connected with the position sensor, the current sensor and the power adapter, the position sensor detects the position of an inner rotor of the motor in real time, the current sensor detects the current in the motor in real time, and the power adapter supplies power to the motor.

5. The PMSM control system of claim 4, wherein the position sensor includes a sensor head secured to an inner wall of the motor housing and a color code secured to the rotor within the motor, the sensor head facing the color code when rotated from a position where the coil is orthogonal to the magnetic induction lines within the motor.

6. The PMSM control system of claim 5, further comprising torque sensors electrically connected to the controller and the motor, respectively, the torque sensors measuring the motor output torque.

Technical Field

The invention relates to the field of automation, in particular to a permanent magnet synchronous motor control method and a permanent magnet synchronous motor control system.

Background

Synchronous permanent magnet motors use alternating current, so in order to improve the operating efficiency of the motor, it is desirable that at the peak of the current, the coils of the inner rotor are just orthogonal to the magnetic induction lines provided by the permanent magnets. If the permanent magnet synchronous motor cannot operate in an ideal working state, on one hand, the output torque of the motor is reduced, on the other hand, some vibration and noise problems are caused, the electromagnetic matching of the motor is not proper, and even motor accidents can be caused.

Disclosure of Invention

The invention aims to overcome the technical defects, provides a permanent magnet synchronous motor control system and a control method thereof, and solves the technical problem that the working efficiency of a permanent magnet synchronous motor is influenced due to the fact that the current and the magnetic field are not matched in the permanent magnet synchronous motor in the prior art.

In order to achieve the technical purpose, the technical scheme of the invention provides a permanent magnet synchronous motor control method, which comprises the following steps:

s1, starting the motor until the rotating speed of the motor is stable;

and S2, calibrating the position sensor and the current sensor to make the delay time of the position sensor and the current sensor consistent.

S3, detecting the position of the rotor in the motor in real time by a position sensor, and detecting the current in the coil in the motor in real time by a current sensor;

s4, recording the time t1 when the induction head faces the color scale, recording the time t2 when the current in the coil reaches the peak value, and obtaining the difference value delta t between t1 and t 2;

s5, judging whether the delta t is smaller than a preset value, if the delta t is smaller than the preset value, ending the control, and if the delta t is larger than the preset value, carrying out S6;

s6, changing the phase of the power supply of the power adapter;

and S7, repeating S2 to S4 until the delta t is smaller than the preset value, and then ending the control.

Compared with the prior art, the invention has the beneficial effects that: the position sensor detects the real-time position of the inner rotor of the motor in real time, the time t1 when the coil on the inner rotor orthogonally cuts the magnetic induction line is recorded, the current sensor detects the current change in the coil in the motor in real time, the peak time t2 of the current is recorded, the controller detects the difference value delta t between t1 and t2, when the delta t is smaller than a preset value, the current in the coil is in the peak value, the working efficiency of the motor is in the highest state, when the delta t is larger than the preset value, the working state of the motor needs to be adjusted, the power supply phase of the power adapter is adjusted at the moment, and when the delta t is smaller than the preset value, the adjustment is finished, and the motor is in the highest working efficiency.

Drawings

Fig. 1 is a schematic structural diagram of a permanent magnet synchronous motor control system according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a position sensor assembly relation according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention provides a permanent magnet synchronous motor control system, comprising: controller 100, position sensor 200, current sensor 300, motor 400, power adapter 500, and torque sensor 600.

The controller 100 is respectively connected with the position sensor 200, the current sensor 300, the motor 400, the power adapter 500 and the torque sensor 600, and the controller 100 receives signals transmitted by the sensors, performs certain logic judgment, and controls the power adapter 500 to change the power supply phase according to the judgment result.

Position sensor 200 is used to detect the real-time position of a rotor within motor 400 in real time, and position sensor 200 includes: the sensor head 210 and the color mark 220, wherein the sensor head 210 is disposed on the inner wall of the casing of the motor 400, and the color mark 220 is fixed on the rotor in the motor 400. In addition, it is also required that the sensing head 210 faces the color scale 220 when the coil on the rotor of the motor 400 is orthogonal to the position of the magnetic induction line formed by the permanent magnet of the motor 400. Therefore, when the sensing head 210 detects the color scale 220, which means that the coils on the inner rotor of the motor 400 cut the magnetic induction lines orthogonally, the position sensor 200 feeds back the sensing signal to the controller 100.

The current sensor 300 measures the current change of the coil in the motor 400 in real time, the selection of the current sensor is not limited, and both the hall type current sensor and the mutual inductance type current sensor can meet the requirements.

The motor 400, which is the object of the present invention to be controlled, is a permanent magnet synchronous motor, and because the position sensor 200 has special installation requirements, to adapt to the installation of the position sensor 200, the inner wall of the motor 400 is reserved with positions for installing the induction head 210, and at the same time, lead holes are reserved for the power supply wires of the induction head 210 to pass through, while the inner rotor of the motor 400 is reserved with space for installing the color scale 220.

The power adapter 500 is used to supply power to the motor 400, and the power adapter 500 is controlled by the controller 100 to change the phase of the power supplied by the power adapter 500, thereby changing the operating state of the motor 400.

It should be noted that, regardless of the position sensor 200 or the current sensor 300, there is a certain delay in the process of feeding back the signal to the controller 100, if the two delays are the same, the accuracy of the permanent magnet synchronous motor control system of the present invention is not affected, but if the two delays are different, the two delays need to be adjusted to be the same. Based on the above problem, the torque sensor 600 is added to verify the delay asynchronism between the position sensor 200 and the current sensor 300.

It should be noted here that the output torque of the motor 400 is at a maximum when the coils on the inner rotor cut the magnetic induction lines at right angles, at the peak of the current. Therefore, although the calibration can be performed by using the torque sensor 600, the change in the torque output from the motor 400 cannot be detected by the torque sensor 600 in a very short time due to the influence of inertia, and thus, the matching relationship between the magnetic field in the motor 400 and the current in the coil is directly adjusted by using the feedback result of the torque sensor 600, which takes a long time, and thus, the method is not practical, but the delay errors between the position sensor 200 and the current sensor 300 can be calibrated by using the torque sensor 600.

Based on the technical scheme, the following control method is adopted:

s1, starting the motor 400 until the rotating speed of the motor 400 is stable;

s2, calibrating the position sensor and the current sensor to make the delay time of the position sensor and the current sensor consistent;

s3, detecting the position of the rotor in the motor 400 by the position sensor 200 in real time, and detecting the current in the coil in the motor 400 by the current sensor 300 in real time;

s4, recording the time t1 when the induction head 210 is over against the color scale 220, recording the time t2 when the current in the coil reaches the peak value, and obtaining the difference value delta t between t1 and t 2;

s5, judging whether the delta t is smaller than a preset value, if the delta t is smaller than the preset value, ending the control, and if the delta t is larger than the preset value, carrying out S6;

s6, changing the phase of the power supply of the power adapter 500;

and S7, repeating S2 to S4 until the delta t is smaller than the preset value, and then ending the control.

It should be noted here that the smaller the setting of the predetermined value, the more accurate the control of the control system, and the present embodiment preferably sets the predetermined value to 0.2ms, while in changing the phase of the power supply of the power adapter 500, the phase of the power supply should be changed stepwise until the change reaches one cycle. Accordingly, the smaller the interval of each phase change, the higher the accuracy of the control.

In addition, for the delay problem of the position sensor 200 and the current sensor 300, the following calibration method is adopted:

s21, detecting that the delta t is smaller than the preset value by the torque sensor 600, and then outputting the torque M0 by the motor 400;

s22, changing the power supply phase of the power adapter 500, and measuring the output torque M1 of the motor 400 after the output torque of the motor 400 is stable;

s23, repeating S2, continuously changing the power supply phase until the phase is changed for a period, and sequentially obtaining a torque M2 to a torque Mn;

s24, obtaining a maximum value Mmax from M1 to Mn, if M0 is larger than Mmax, the sensor delay does not need to be calibrated, and if M0 is smaller than Mmax, the phase difference between the phase corresponding to Mmax and the phase corresponding to M0 is the delay difference ξ between the position sensor 200 and the current sensor 300;

s25, delaying the feedback signal of the position sensor 200 by ξ, checking whether the delta t is smaller than a preset value, if so, finishing calibration, and if the delta t is larger than the preset value, then, the current sensor 300 is started

The feedback signal is delayed by 2 ξ to complete the calibration.

The above-described embodiments of the present invention should not be construed as limiting the scope of the present invention. Any other corresponding changes and modifications made according to the technical idea of the present invention should be included in the protection scope of the claims of the present invention.