A flying start method suitable for high-speed permanent magnet synchronous motor

Abstract

The invention discloses a flying start method suitable for high-speed permanent magnet synchronous motors, which includes: establishing an estimated rotating coordinate system, and implementing a control strategy for setting the excitation current and torque current to zero for the current loop; Sampling to obtain the estimated current of the rotating coordinate system; establish the actual rotating coordinate system based on the actual state of the motor rotor, obtain the angle between the two coordinate systems according to the modulation voltage of the PI regulator, and obtain the current motor speed by deriving the angle; repeat In the above steps, the current motor speed is estimated multiple times, and after confirming that the identification speed is correct, switch to the normal operation mode; the inverter accelerates to the target speed according to the current motor speed, and completes the flying start process. The method can accurately estimate the current actual speed of the permanent magnet synchronous motor when there is no speed sensor and the flux observer fails, and can quickly realize smooth switching and complete the flying start of the high-speed permanent magnet synchronous motor.

Description

technical field [0001] The invention relates to the technical field of motor starting, in particular to a flying start method suitable for high-speed permanent magnet synchronous motors. Background technique [0002] Compared with asynchronous motors, traditional permanent magnet synchronous motors, especially rare earth permanent magnet synchronous motors, have the advantages of less loss, high efficiency, and obvious power-saving effects, especially in position control, speed control, and torque control. As the cost of permanent magnet materials has dropped in recent years, permanent magnet synchronous motors have been rapidly promoted, but the ensuing problem is that in some occasions with high inertia, it takes a long time for the motor to stop freely or stop after a fault , which causes a lot of trouble for restarting in a short time interval. In view of this situation, the permanent magnet synchronous motor needs to have the function of flying start. Different from t...

AI Technical Summary

Problems solved by technology

As the cost of permanent magnet materials has dropped in recent years, permanent magnet synchronous motors have been rapidly promoted, but the ensuing problem is that in some occasions with high inertia, it takes a long time for the motor to stop freely or stop after a fault , which causes a lot of trouble for restarting in short time intervals

Different from the flying start of the asynchronous motor, the permanent magnet synchronous motor does not allow slip, so a special strategy is needed to complete the flying start of the permanent magnet synchronous motor. For the high-speed permanent magnet synchronous motor with low back EMF, the flying start The difficulty is greatly increased

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