Inverter fault-identification for VSI motor drives

The paper presents an identification procedure able to detect open circuit failures in voltage source inverters. The procedure is suitable to equip fault tolerant electric motor drives and in principle only requires the measurement of the DC link current as it accomplishes a reconstruction of the inverter output phase currents from the DC link current measurement, thus eliminating the need of conventional current sensors. However, if they are present at the cost of minimal modifications the PWM technique, response times as short as one switching period can be obtained. Compared to other technical solutions found on past literature, the proposed approach considerably reduces the required computational effort. Simulations and experimental tests are presented to confirm the consistence of the proposed approach.