A new technique for simultaneous detection of one to two open-switch faults in three phase voltage-inverter-fed pm brushless DC motor drive

The faulty performance of permanent-magnet (PM) brushless dc motor drives is studied under one and simultaneous two open-switches faults conditions. This DC motor is supplied with a three phase two level six IGBT voltage source inverter. The three phases currents mean values of the DC motor are used as diagnostic indices. A knowledge algorithm is based to get information on which IGBT is in open-switch fault condition. This algorithm testing shows that the system could not only detect the open-switch fault, but also identify the faulty switch. Presented simulation results confirm the effectiveness of the proposed methodology.