Fault diagnosis method for motor turn-to-turn short circuit based on high frequency signal injection

Abstract

The invention discloses a motor inter-turn short-circuit diagnosis method based on high-frequency signal injection, which is used to solve the problem of high-precision identification of motor winding inter-turn short-circuit faults, and belongs to the technical field of measurement and testing. This application injects sinusoidal high-frequency currents with equal amplitude and 180° phase difference into the two-phase windings of the motor where the inter-turn short-circuit fault of the windings is to occur, extracts the high-frequency components with the same frequency as the injected high-frequency signal from the two-phase line voltage, and calculates Fault characteristic quantity. According to the comparison result of the fault characteristic quantity and the set threshold value, the conclusion whether the inter-turn short circuit fault occurs in the two-phase winding injected with high-frequency current is obtained, and the state of the winding is recorded, and each winding is fitted with other windings after injecting high-frequency current. The winding state product is obtained to identify the flag bit of the faulty phase winding, and the diagnosis result of the motor winding is given. The invention can diagnose the inter-turn short circuit of the motor winding on-line, and has high sensitivity to the inter-turn short circuit fault.

Description

technical field [0001] The invention belongs to motor fault diagnosis technology, in particular to a motor winding turn-to-turn short-circuit fault diagnosis method based on high-frequency signal injection, and belongs to the technical field of measurement and testing. Background technique [0002] Permanent magnet synchronous machine (permanent magnet synchronous machine) uses permanent magnets to provide rotor flux, and eliminates complex excitation devices. It has the advantages of high power factor, high operating efficiency, and high reliability. In recent years, it has been used in wind power generation and electric vehicles. field has been widely used. [0003] Permanent magnet synchronous motor faults mainly include two types, one is electromagnetic faults including stator winding short-circuit faults and rotor demagnetization faults, and the other is mechanical faults including rotor eccentricity and bearing damage. Most faults associated with stator windings are i...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to address the deficiencies of the above-mentioned background technology, and provide a fault diagnosis method for inter-turn short-circuit faults of motors based on high-frequency signal injection. The method for intermittently injecting high-frequency signals is used to flexibly arrange inter-turn short-circuit detection of motor phase windings, which improves the The detection sensitivity of inter-turn short-circuit faults solves the technical problems that the detection sensitivity of existing motor inter-turn short-circuit faults is poor and the diagnosis results are easily affected by factors such as changes in working conditions

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