Abstract—
A single-phase induction motor using a new 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 ma¬chine performance. Basic system operation, a comparison with conven¬tional motor operation, and illustrations of some of the design flexibility inherent in the new system are included.


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http://lipo.ece.wisc.edu/1980s%20pubs/88-15T.pdf