| 摘要 |
Proposed is a highly versatile drive apparatus capable of supporting various electric motors regardless of the characteristics of the structure, the materials used, or the like of an alternating-current electric motor, as a method for achieving stable drive from a stop or a low speed level without using the rotor position sensor of the alternating-current electric motor. The present invention is provided with a circuit for detecting a hypothetical neutral point potential of the alternating-current electric motor, and a circuit for generating a reference voltage that differs from the potential, and by increasing the differential between the two circuits, a striking voltage is obtained due to the variation in the position of the rotor, and on the basis of this striking voltage, the energizing phase of the alternating-current electric motor is switched, whereby the alternating-current electric motor can be stably driven at a constant speed. The striking voltage value varies according to the type and specification of the motor, but these can be generally supported by adjusting the gain of the amplifier. |
