A method to improve the starting performance of permanent magnet synchronous motor without position sensor control

Abstract

The invention discloses a method for improving the sensorless control starting performance of a permanent magnet synchronous motor. The method comprises determining whether the peak value of a windingphase current in an open-loop operation mode matches a load according to a difference between the position angle of an active rotating magnetic field and the estimated rotor position angle in the open-loop operation mode, and if not, readjusting the peak value of the winding phase current of the motor until the peak value matches the load. The method of the invention can avoid a starting failurecaused by low open-loop starting torque when the peak value of the winding phase current of the motor is small in the event of a heavy load, and a starting failure caused when the peak value of the winding phase current of the motor is large in the event of a light load and thus causes large open-loop starting torque and overshot energy and causes that an estimated algorithm does not converge because of switching from an open-loop position to an closed-loop position.

Description

technical field [0001] The invention relates to the technical field of motor control, in particular to a method for improving the starting performance of a permanent magnet synchronous motor without position sensor control. Background technique [0002] Permanent magnet synchronous motor has the advantages of simple structure, high power density, high efficiency, wide speed range, etc., and has been widely used in industrial control, home appliances and other fields. The position sensorless control technology of permanent magnet synchronous motor can reduce hardware cost and improve system reliability. In recent years, it has become a very important research direction in the field of motor control. The closed environment, where the rotor position sensor cannot be installed, is very suitable for the position sensorless control scheme. Since the rotor position angle of the permanent magnet synchronous motor is difficult to estimate accurately when the permanent magnet synchro...

AI Technical Summary

Problems solved by technology

In order to solve the problem of estimating the rotor position angle of the motor at rest, Jia Hongping and others proposed a permanent magnet synchronous motor rotor initial The position detection method, the high-frequency injection method can accurately detect the rotor position angle under static conditions, thereby improving the starting ability of the motor, but this method has disadvantages such as long algorithm execution time and complicated implementation process

[0003] The permanent magnet synchronous motor position sensorless control technology widely used in the existing frequency conversion air conditioner compressors, many adopt the start-up mode of open-loop self-synchronization operation and then switch to the rotor position closed-loop. This kind of start-up algorithm has a short execution time and is easy to implement in engineering , but the starting ability is not as good as the high-frequency injection method, and it is easy to fail to start when the load is heavy

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