A new approach to analysis of induction motors with rotor faults during startup based on the finite element method

Abstract

The increasing popularity of a so-called transient motor current signature analysis requires the fault diagnostics parameters which could not be exposed to other factors irrelevant to the fault to make a precise assessment of the failure severity level. This challenging task needs a precise modeling of faulty motor behavior in various operating conditions at different fault severity levels. This paper introduces a new approach to the finite element analysis of an induction motor with broken rotor bars during startup. The approach is based on the principle of superposition and contributes to examination of the fault rotor backward rotating magnetic field and current components produced by such field separating them from stator currents. It gives a new sight on the behavior of a faulty motor during startup for the diagnosis purposes. Further analysis of the simulation data by means of the Extended Park's Vector Approach and the continuous wavelet transform and its experimental validation is also presented in the paper.