Simplified Pre-Analysis of Fault Severity for Interturn Short-Circuit Faults in Fault-Tolerant Permanent Magnet Machines

This letter proposes a simplified offline preanalysis method of fault severity for interturn short-circuit faults (ISCFs) in fault-tolerant permanent magnet synchronous machines (FTPMSMs). For fault diagnosis and fault-tolerant (FT) control, it is important to predict how much short-circuit current will be generated at various speeds, loads, shorted turns ratios, and fault resistances. However, predicting the short-circuit current usually needs to solve differential equations by closed-loop simulation or finite element analysis (FEA). To increase the efficiency of fault preanalysis, the proposed method provides a simple solution to quickly offline predict the amplitude of short-circuit current. Simulation and experimental results show the effectiveness of the proposed method for different fault severities and various operations.