A switched multi-tapped transformer-based power conversion circuit is disclosed. A polarity alternator comprising dual switch devices controlled by a microprocessor selectively periodically impresses across a transformer's center-tapped primary winding a voltage from a battery to produce a modified square...http://www.google.com/patents/US5155672?utm_source=gb-gplus-sharePatent US5155672 - Switched multi-tapped transformer power conversion method and apparatus
