Over-voltage mitigation on SiC based motor drives through an open end winding configuration

An original overvoltage mitigation technique is presented in this paper for Sic based motor drives, exploiting an open-end winding motor configuration. According to the proposed solution over-voltage occurring at the terminals of the motor phases is mitigated by driving the two inverters through a modified switching pattern including a suitable dwell time. No passive RLC networks are required, thus avoiding additional costs and extra power losses. A comparison between IGBT and SiC MOSFET equipped motor drives is first provided, highlighting the difference in terms of power cable critical length and other factors affecting peak terminal over-voltages. The proposed approach is then theoretically introduced and its consistency is finally assessed by simulations and experimental results.