| 摘要 |
PURPOSE:To improve the operating efficiency of a commutatorless motor in a low speed range at the time of low load of the motor by directly detecting the reverse voltage time of the thyristor group of power inverter to control constantly the allowable commutation time. CONSTITUTION:A synchronizing signal A and gate signal groups D becoming a commutation reference are obtained by a position detection signal and inverted detection signals in a distributor 5. The signal A is inputted to an F/V converter 6 and a gamma set pulse generator 9, the allowable commutation time command signal from a gamma set pulse generator 9 is compared by a comparator 10 with an allowable commutation time detection signal from an allowable commutation time detector 8, and becomes a DC level signal H through a deviation amplifier 11. On the other hand, A triangular signal B obtained through the converter 6 and the generator 7 is compared with the DC level signal H by a comparator 12, a signal C being obtained by the comparison is inputted to a gate logic circuit 12, a reference gate signal D is shifted in phase in response to the width of the signal C, thereby obtaining a predetermined gate signal. |
