Search Coil Based Detection of Inter Turn Short Circuit Faults in Permanent Magnet Synchronous Machines

This paper describes search coil based detection of inter turn short circuit (ITSC) faults in permanent magnet synchronous machines (PMSM) in electrical aviation applications. Various possible cases of ITSCs as well as their effects on the operation of the machine are investigated. The possibility of detecting the ITSC fault cases by using additionally inserted detection coils is examined. The results of different circuits and arrangements of these search coils are compared. The investigation considers an exemplary machine model analyzed via FEA. The considered surface PMSM is designed with double layer single tooth coil winding and could be used to directly drive a propeller aircraft.