103 / 2021-06-18 14:22:11

Diagnosis of Current Sensor Faults in Open Winding Permanent-Magnet Linear Motor Drive Systems

Fault diagnosis， open winding permanent-magnet linear motor， current sensor， gain fault， zero-offset fault

In this article, a fault diagnosis method of current sensors for open winding permanent-magnet linear motor (OWPMLM) drive systems was proposed. For the gain fault and zero-offset fault, the signal fault characteristics is different from that of traditional machine with Y-connected winding. This means that existing methods cannot be directly to diagnosis these faults in OWPLM drive systems. In the proposed method, d- and q-axis currents are estimated by a current observer. The residual errors are calculated by estimated and measured currents. The fluctuation amplitude of current error is used to judge the fault. The fluctuation period of current error is used to distinguish the fault type, and the fault diagnosis index is used to locate the fault phase. This proposed method can detect fault, distinguish fault type and locate fault phase effectively. Finally, simulations verify the effectiveness of the proposed fault diagnosis method.