A method for power converter fault diagnosis

Electrical failure of power converter will greatly affect switched reluctance motor (SRM) systems. Based on four typical faults, the fault procedure and consequence of power converter are analyzed in detail. Due to obvious fault characteristics of the freewheeling current, this paper proposes a fault diagnosis scheme based on the freewheeling current. Power converter operates in excitation phase and freewheeling phase and faults happening during different phases will result in change in freewheeling current. Fault characteristics are obtained on the basis of changes of the freewheeling current and transformed to electrical lever jumping based on digital thought to obtain a effective fault diagnosis scheme will. Finally, the scheme will be verified through simulation experiments. The results show that this scheme utilizes more fault characteristics and diagnoses faults more accurately compared with the fault diagnosis scheme based on only phase current.