A commutator circuit includes a bridge (1), which may have a half-bridge or a full-bridge topology, and a switch resonant arm (3, L, C). The resonant arm is coupled to the midpoint of the bridge, directly, or via a current buffer, or via a transformer. The arm provide controlled resonant commutation...http://www.google.es/patents/US5917722?utm_source=gb-gplus-sharePatente US5917722 - Controlled commutator circuit
