| 摘要 |
PURPOSE:To increase the stability and the reliability of a controller for a DC commutatorless motor by advancing instantaneously the firing phase of a thyristor when the commutation of a thyristor power converter circuit fails to increase the length of an allowable commutation time and enabling the automatic commutation. CONSTITUTION:The commutation failure of an inverter 4 is detected by a commutation failure detector 6 when it occurs, a switch 12a is switched to a contact b by a changeover logic 11, and the signal of a firing angle beta of 60 deg. is supplied to a gate logic 21, and the reverse voltage period of the thyristor of the inverter 4 is increased in this manner. Simultaneously, set gamma amount of a gamma set pulse generator 16 and equal polarity signal ADD.gamma are applied to a matching circuit, thereby setting a deviation amplifier 17 to maximum advance of gamma. Thus, the reverse voltage period can be lengthened, and when recommutated, the logic 11 can be returned to the original operating direction, so that the ADD.gamma becomes ''0'', and the gamma becomes constant. When the commutation still failed in the state of the contact b of the switch 12a continues, a start stop circuit 23 is operated by the prescribed operation of a timer 22 for counting the output of the circuit 6, thereby stopping the operation of the device. |
