| 摘要 |
PURPOSE:To reduce the size of an induction motor starting system by converting DC current to AC current via an inverter and controlling the frequency, thereby gradually increasing the frequency to start the motor with the low current. CONSTITUTION:A DC current obtained from a solar battery 1 is converted via a rectangular wave inverter 3 into an AC current, the frequency is controlled to be gradually increased, thereby starting an induction motor 2. In this manner, the frequency is controlled by the inverter, thereby gradually increasing the frequency to start the motor. Accordingly, large current is not necessary to start the motor, and it is not necessary to provide a solar battery of large capacity larger than the ordinary operating time current capacity as the conventional one. |
