Methods to Deter006Dine the Stator Inter-turn Short Circuit in an Induction Motor with Installed Rotor

摘要

Most of the insulation failure on induction motor stator windings occurs because of a short circuit between turns (turn-to-turn), which leads to total breakdown. Surge test on stator windings is one of the most common tests to detect symptoms of the fault. Usually, a surge test is applied to a stator winding without the rotor. This paper proposes an evaluation method for surge tests with the condition that the rotor remains attached. Two parameters are defined to identify the fault’s existence inside the rotor winding; those are Error Area Ratio (EAR) and Zero Crossing Point (ZCP). The rotors are rotated gradually, and the surge test is applied. EAR and ZCP values are calculated for each rotor position. Following that, all EAR and ZCP values of all rotor positions are added to become ΣEAR and ΣZCP. These two parameters are used to detect any damage to the windings. The result shows that by using these two parameters, the short circuit on the stator can be identified very sensitively, including as small as a half-percent (0.5%) short circuit of the total winding.