| 摘要 |
PROBLEM TO BE SOLVED: To suppress a change of a power supplied to a load when a plurality of power sources are used to drive the load. SOLUTION: In order to drive a three-phase AC motor 1 by a power from a battery 21 and a capacitor C1 or a smoothing capacitor C2; a first switch S1, a second switch S2, and a third switch S3 are switched so as to have the battery 21 and the capacitor C1 connected to an inverter unit 13 in series with each other, in parallel with each other, or independently from each other, or not to have the battery 21 and the capacitor C1 connected to the inverter unit 13. At that time, the first switch S1, the second switch S2, and the third switch S3 are controlled by a power source control circuit 23 according to a battery voltage Vb, a capacitor voltage Vc, and a power operation/regenerative operation state of the three-phase AC motor 1, so as to obtain connection relations of the switches which can suppress a change of a power supplied from the inverter unit 13 to the three-phase AC motor 1. |
