| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the occurrence of uneven rotation of the rotor of a synchronous motor. <P>SOLUTION: A control circuit 50 sets the on-time THon of a switching element on the positive bus 22 side and the on-time TLon of a switching element on the negative bus 21 side so that the following imbalance is repaired: imbalance between the potential difference (VH-VB) between the positive bus 22 and the neutral point 1x of a stator coil 1 and the potential difference (VB) between the negative bus 21 and the neutral point 1x of the stator coil 1. The on-time THon of the switching element on the positive bus 22 side is shortened with increase in the potential difference (VH-VB). The on-time THon of the switching element on the positive bus 22 side is lengthened with decrease in the potential difference (VH-VB). This prevents fluctuation in the magnitude of magnetic flux produced in each of a U-phase coil 1a, a V-phase coil 1b, and a W-phase coil 1c. Thus the unevenness of a rotating magnetic field produced from the stator coil 1 is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT |
