3T-Y winding connection for three phase multiple-speed motor

A three-phase, multi-speed electric induction motor assembly is configured to include a controller to change motor speeds. The motor assembly includes a stator core assembly, a pair of main winding coil groups corresponding with each phase, and a pair of selectable extra winding coil groups corresponding with each phase. During the lower-speed operation, the controller connects a first set of three leads to a power source such that only the main coil groups are energized. During the higher-speed operation, the controller connects a second set of three leads to the power source such that both the main coil groups and the selectable extra coil groups are energized.