| 摘要 |
PURPOSE:To make it possible to reduce a load to a battery and operate for a longer period of time by giving an ordinary power in the initial stage of motor drive and then giving a smaller power than the initial power after the elapse of a certain period of time. CONSTITUTION:An output from a battery 2 is converted into AC by a switching element 9, rectified and smoothened by a rectifier 11 and smoothening circuit 13 and then supplied to and AC motor 23 through an inverter 18. Rotating speed of the AC motor is controlled by the inverter circuit 18. Width of pulses output from a pulse width-varying clock pulse generator 51 will be made wider for a certain period of time after the start of the AC motor 23 but made narrower thereafter. By doing this, the voltage supplied to the AC motor 23 becomes higher during start and lower at ordinary times, thereby reducing power consumption during steady-state operation. |
