Single phase induction motor with an electronically controlled capacitor

A single-phase induction motor using a novel electronically controlled capacitor is described. The system uses a DC capacitor switched by a transistor H bridge. By proper control of the transistor switching the circuit synthesizes a continuously variable capacitance in series with the auxiliary winding. The system could be used to replace standard single-phase motor capacitor configurations to provide improved machine performance. A description of basic system operation, a comparison with conventional motor operation, and illustrations of some of the design flexibility inherent in the proposed system are included.<>