Method and device for measuring alternate and direct axis induction of permanent magnet synchronous motor

Abstract

The invention relates to a method and device for measuring alternate and direct axis induction of a permanent magnet synchronous motor, which are characterized in that any one phase winding of the permanent magnet synchronous motor is disconnected respectively, and the remaining two phase windings are electrified with a power frequency alternate current of a certain amplitude; and within a certain period, corresponding line voltage and line current are sampled at fixed time, and the line inductance as well as the alternate axis inductance and the direct axis inductance of the three-phase winding can be calculated according to the formula. The device for measuring alternate and direct axis induction of the permanent magnet synchronous motor is formed through the method for measuring alternate and direct axis induction of the permanent magnet synchronous motor, and comprises an isolation step-down transformer, an isolation sampling circuit, a controllable change-over switch, a single microcontroller, a liquid crystal display screen and a direct current stabilized power source. The method and device provided by the invention realize the purpose of automatically, quickly, and accurately measuring the alternate and direct axis inductance of the permanent magnet synchronous motor without any instrument, rotor positioning and manual intervention.

Description

technical field [0001] The invention relates to a method and a device for measuring the AC-D axis inductance of a permanent magnet synchronous motor, in particular to a device for automatically measuring the AC-D axis inductance and the D-axis inductance of a permanent magnet synchronous motor used for vector control, belonging to the field of motors. Background technique [0002] The position sensorless permanent magnet synchronous motor with vector control is more and more widely used in the fields of industry and home appliances, and the core of its system operation characteristics depends on the accuracy of the motor's AC-D axis inductance parameters. At present, the test methods used to measure the AC-D axis inductance of permanent magnet motors mainly include voltage integration method, direct decay method, etc., but these methods need to rotate the motor rotor to the position of the D-axis or Q-axis. In actual measurement, due to the direct current Due to the influenc...

AI Technical Summary

Problems solved by technology

At present, the test methods used to measure the AC-D axis inductance of permanent magnet motors mainly include voltage integration method, direct decay method, etc., but these methods need to rotate the motor rotor to the position of the D-axis or Q-axis. In actual measurement, due to the direct current Due to the influence of the magnetic field, it is difficult for the rotor to reach the designated position, and various instruments such as voltmeter, ammeter, power meter and oscilloscope are required to manually obtain test data. The test device is too complicated, the test time is relatively long, and the test accuracy is difficult to guarantee.

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