| 摘要 |
PURPOSE:To control rush current at the time of starting of a motor by providing a capacitor for time delay and by enlarging gradually a continuity angle of a semiconductor control element controlling the voltage impressed on the motor. CONSTITUTION:A series circuit of a resistance 8 and a capacitor 9 for controlling phase, a series circuit of a diode 5, a resistance 6 for time delay and the capacitor 7 for time delay, and a series circuit of a resistance 10 and a transistor 12 are connected in parallel and further the capacitor 7 and resistance 6 are provided with a capacitor 18 for smoothing and a resistance 19 for discharge, while the capacitor 9 is connected in parallel with PUT15, and thus the motor 3 is controlled with the semiconductor control element 4 as a continuity. Accordingly, by selecting the time constant of the capacitor 7 to be larger than the time constant of the capacitor 9 and by enlarging gradually the continuity angle of the semiconductor control element 4 dependently on the both-end voltage of the capacitor 7, the motor 3 is started softly and thus the rush current can be controlled. |
