| 摘要 |
PURPOSE:To obtain a wide phase voltage range by a method wherein respective transistors of an inverter are controlled so as to be put ON/OFF by the outputted ON/OFF switching time of respective phases. CONSTITUTION:The ON/OFF switching times of the inverter switching elements QW1, QW2 of W-phase are fixed in a constant condition during a pulse width modulating period by the commanding voltages of U-phase and V-phase, for example, while the ON/OFF switching time of the U-phase and the V-phase are obtained based on the fixed ON/OFF switching time of the W-phase. The ON/OFF controls of the inverter switching elements QU1, QU2, QV1, QV2, QW1, QW2 of the U-phase and the W-phase are effected by the obtained ON/OFF switching times of the U-phase and the V-phase. According to this method, a wide phase voltage range may be obtained. |
