| 摘要 |
PURPOSE:To stably control the speed of a 3-phase induction motor while simplifying the motor and reducing the weight of the motor by driving a triac which energizes the motor by a single pulse control circuit. CONSTITUTION:3-phase induction motor 1 is energized through triacs 2-4 which are connected at the terminal T1 to the power source side at the respective phases R, S, T from a 3-phase AC power source. One respective terminals of 3 condensers 11-13 are respectively connected to 3-phase AC power sources R, S, T, the other respective terminals are connected to the AC sides of a 3-phase full-wave rectifier 17, and variable resistance elements made of phase controlling transistor 19 and resistors 18 are connected to the DC side of the rectifier 17, thereby constructing a phase control circuit. The gate circuits of the triacs 2- 4 are composed of trigger diodes 21-23. |
