Comparative Study on Fault-Tolerant Triple Three-Phase PM Machine Drive With Five Modular Windings

Abstract

In this paper, five different triple 3-phase windings are presented for fault tolerant PM machine drive to achieve advanced turn short circuit fault (TSCF) current reduction effect. First, the five different winding configurations are briefly introduced and the reasons of TSCF reduction effect is explained. Then, the healthy performance and fault tolerant capabilities of several fault modes are investigated by detailed finite element (FE) prediction and test verification. They exhibit almost the same healthy performance. It is demonstrated that the zero sequence (ZS) flux linkages in Y connected winding is the fundamental factor of the huge TSCF current since the Y winding does not contain ZS current path. Thus, the Y-Δ winding exhibits the best the TSCF current suppression capability which creates the ZS current path to nullify the ZS flux linkages, and the delta winding ranks as the second which contains larger ZS circuit. The investigation provides effective approaches and solutions to obtain enhanced fault tolerant capability on the worst TSCF for the safety critical applications.