THE FAULT-DIAGNOSIS OF ROTOR BARS IN SQUIRREL-CAGE INDUCTION-MOTORS BY TIME-STEPPING FINITE-ELEMENT METHOD

This paper presents a fault diagnosis of the rotor bars in squirrel ca ge induction motors. The defective rotor bars such as broken bars and high resistance are detected by analyzing the induced current in the c oil caused by reluctance variation when the rotor is moving. In the an alysis, the time stepping finite element method is used where the elec tromagnetic and circuit equations are coupled and the rotor movement i s considered by automatic subdivision of air gap meshes. By the propos ed method, various rotor fault conditions are simulated. The experimen tal results show that the analysis method is useful to detect rotor fa ult conditions.