公开(公告)号：US3703672A

公开(公告)日：1972-11-21

申请号：US3703672D

申请日：1971-04-26

Applicant: NAT RES DEV

Inventor： BIRD BRIAN MICHAEL ,  RAWCLIFFE GORDON HINDLE

IPC: H02P27/06 ,  H02P5/40

CPC classification number: H02P27/06

Abstract: A method of changing the speed of a three-phase induction motor by deriving from the A.C. supply a modulating wave of submultiple frequency, deriving therefrom a corresponding rectangular wave, modulating each phase of the supply by three such modulating waves, with the same sequence or opposite sequence to the supply phases. Modulation of the supply is effected by gating thyristors from the modulating waves. By varying the modulation frequency, the motor speed is varied stepwise over a speed range.

Abstract translation: 通过从交流电源提供三相感应电动机的速度的方法，通过三相这样的调制波调制每个相位的相应的矩形波，从而产生一个次多频的调制波 序列或与供应阶段相反的序列。 电源的调制通过从调制波中选通晶闸管来实现。 通过改变调制频率，电机速度在速度范围内逐步变化。