PERMANENT MAGNET SYNCHRONOUS MOTOR DRIVING SYSTEM

摘要

To provide a PMSM driving system that performs a fail-safe operation while avoiding a short-circuit of upper and lower arms by detecting short circuit fixation or open fixation in a switching element.SOLUTION: A control device of an inverter 20 for driving a PMSM includes: a control calculation unit 52 that performs control calculation using respective phase output currents; and a gate driving circuit 51 that generates a gate signal on the basis of the outputs. The control calculation unit 52 includes: an abnormality detection function 52b that detects short circuit fixation or open fixation in a semiconductor switching element; a phase current detection function 52a that detects the respective phase output currents of the inverter 20; and a control sequence processing function 52c that short-circuits stator winding of the PMSM by turning on a switching element of an upper arm or a lower arm in all phases while avoiding a short-circuit of upper and lower arms in the inverter 20 in accordance with the balance state of the respective phase output currents when an abnormality is detected.SELECTED DRAWING: Figure 2