Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Active Short Circuit Control Method to Reduce Overcurrent and Oscillation Current in PMSM
Authors Jong-Won Choi ; Yoon-Jae Kim
Page pp.339-347
ISSN 1229-2214
Keywords ASC(Active Short Circuit); Functional safety; Safe state; Freewheeling; Traction inverter; Electric vehicle
Abstract This study proposes the mitigation method for overcurrent and oscillation motor current in an active short-circuit operation. This operation is attracting attention as the safe state of electric vehicle traction inverters. However, the active short-circuit operation generates oscillation and overcurrent of motor currents during a transient state. The proposed method uses two different safe states in PMSM, such as active short circuit and freewheeling. The active short circuit is used for safe state in a steady state. To reduce the overshoot and oscillation, a freewheeling state is injected between active short-circuit operation by comparing the motor phase current with an analytically calculated steady-state motor current. Freewheeling state is only used in a transient state. The performance is demonstrated through simulations and experimental results. The peak current of the motor was reduced from 52 A to 40 A, and oscillation time was reduced.