SWITCHING TRANSIENTS IN THREE-PHASE INDUCTION MOTORS RUN ON SINGLE PHASE SUPPLY

The subject of switching transients in polyphase induction motors and synchro-nous machines has been studied in very great detail by several investigators in the past, but no published factual data exist dealing with the analysis of the problem of switch-ing transients in a three-phase induction motor run as a Capacitor Motor on single phase supply. This particular problem has been studied in this paper in detail by applying the Laplace Transform in a slightly modified form. It is shown that the developed electrical torque and the voltage across the con-denser do not exhibit any abnormal values during the first few cycles after the closing of the switch, whether switching is done at the maximum value or zero value of the applied voltage. This result is in striking contrast with the results obtained earlier with a plain general purpose Capacitor Motor