| 摘要 |
In a motor drive device (30), a motor drive unit (38) outputs drive voltages (SU, SV, SW) to a motor portion (24). A switching unit (42) switches between the conduction and disconnection of a GND wire (L1) connecting the lower potential side of the motor drive unit (38) and a DC voltage generation unit (31). A body control microcomputer (43) controls the operation of the motor drive unit (38). The body control microcomputer (43) controls the operation of the switching unit (42) such that when a voltage value detected by a voltage detection unit (34) is less than a first threshold value (ΔTh1), the GND wire (L1) is made conductive and when the voltage value is greater than or equal to the first threshold value (ΔTh1), the GND wire (L1) is disconnected. A first reverse current prevention diode (D6) is disposed between the motor drive unit (38) and the body control microcomputer (43) and prevents current from flowing from the DC voltage generation unit (31) to the body control microcomputer (43) through the motor drive unit (38) when the GND wire (L1) is disconnected by the switching unit (42). |
