Short-circuit fault diagnosis method for stator winding in AC motor

摘要

PROBLEM TO BE SOLVED: To provide a short circuit fault diagnosis method capable of estimating the number of fault phases and fault turns of an AC motor without troublesome calculations even in a simple environment where two sensors are provided.SOLUTION: The short circuit fault diagnosis method includes a step S11 for obtaining a positive phase admittance Yby analysis or the like; a step S12 for obtaining a stator current value at intervals of a fixed period; a step S 13 for obtaining a current park vector I based on the stator current value; steps S14, S15 for obtaining a positive phase component Iand a reverse phase component Iof the current park vector I by assignment using a method of least squares; a step S16 for obtaining an asymmetric admittance Yfrom a positive phase admittance Yand a positive phase component Iand a reverse phase component Iof the current park vector I; and a step S17 for obtaining short circuit fault information based on the asymmetric admittance Y.