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 using an equivalent thermal circuit of a typical IM and by tests. The results of the research make it possible to determine more accurately the permissible values of the current and load when one of the supply phases is disconnected. Both star and delta connections of the stator winding are considered. The losses in IM windings at the one-phase supply are estimated by using the symmetrical components method.