Voltage source inverter fault diagnosis in variable speed AC drives, by Park´s vector approach

This paper presents the use of the Park´s vector approach for diagnosing voltage source inverter faults, like output single-phasing and the occurrence of either a short-circuit or an open circuit of the controlled power switches. For this study, a prototype was built, having all the power terminals available for testing, including the ones for every semiconductor. For the short-circuit tests, a 17 Ω auxiliary resistor was used, connected in parallel with the power switch to be tested, in order to limit the short-circuit current