Investigation of single-switch short-circuit fault characteristics of a PM machine drive with a current source inverter

This paper investigates the single-switch short-circuit fault response of a permanent magnet (PM) machine drive using a current source inverter (CSI). The CSI offers some appealing advantages over conventional voltage-source inverters (VSIs) during short-circuit fault conditions originating inside the inverter. Two post-fault strategies are investigated in this paper, consisting of either: 1) turning off all of the switches; or 2) turning on all of the switches in a controlled manner. Key features associated with the machine response to both of these post-fault strategies are presented and compared, leading to the conclusion that both make it possible to protect the machine. A combination of analysis, simulation, and experimental tests has been adopted for carrying out this investigation.