Heat conditions of a three-phase induction motor by a one-phase supply

The thermal conditions of a three-phase induction motor (IM) with one phase disconnected are investigated. The research is carried out theoretically u sing an equivalent thermal circuit of a typical IM and by tests. The result s of the research make it possible to determine more accurately the permiss ible values of the current and load when one of the supply phases is discon nected. Both star and delta connections of the stator winding are considere d. The losses in IM windings at the one-phase supply are estimated by using the symmetrical components method.