Motor driving circuit

Abstract

To restrain overvoltage in a capacitor during Δ-connection driving.SOLUTION: A motor driving circuit includes a capacitor connected between both ends of a battery, a first inverter, a second inverter, a three-phase motor, a first switch provided between a high-potential wire of the first inverter and a high-potential wire of the second inverter, a second switch provided between a low-potential wire of the first inverter and a low-potential wire of the second inverter, and a control device. When the voltage between a positive electrode and a negative electrode of the capacitor rises to a reference value or more while Δ-connection driving is being performed, the control device turns off the first switch, the second switch, three first upper arm reverse conducting switching elements, three first lower arm reverse conducting switching elements, three second upper arm reverse conducting switching elements, and three second lower arm reverse conducting switching elements.SELECTED DRAWING: Figure 1