| 摘要 |
A balanced and synchronized phased detector circuit is provided for a three phase power controller for AC induction motors. The power controller includes a thyristor or switching element for each motor phase winding between a line phase terminal of a three power line and the motor's input terminals, and decides the sequence for firing the thyristors. The phase detector includes a dividing resistor network between each phase's line terminal and the front-end operational amplifiers used in the phase detector, and an adjustable dividing resistor network between each motor terminal and the front-end operational amplifiers. The resistor networks allow a differential voltage to be set between the phase line terminal and the motor terminal for each phase, to a voltage appropriate for firing the respective thyristor. By allowing control over the front-end differential voltage, the phase detector virtually elements vibrations encountered during operation of the motor. |
