Patent ID: 7248015

Claim:
A control system for controlling the speed of a variable speed permanent split capacitor (PSC) motor having an auxiliary winding configured to provide torque for initial motor startup and a run winding configured to provide continuous motor operation, the motor being coupled to a capacitor configured to direct a portion of a current through the run winding when the PSC motor reaches its intended speed, the control system comprising: a speed control unit coupled between a voltage line and the PSC motor, wherein the speed control unit is configured to control the speed of the PSC motor; and a bypass circuit coupled between the voltage line and the capacitor via a first path, wherein the bypass circuit is configured to receive a control signal from the speed control unit via a second path and to regulate a chopped voltage wave form generated by the speed control unit such that at least a portion of the chopped voltage wave form is not applied to the capacitor.