Low cost inverter suitable for medium-power fuel cell sources

A low-cost high performance fuel cell inverter for 48 V to 120 V/sub ac/ conversion is described. The design addresses total system cost including battery and battery management while providing a current sourced interface for the fuel cell and galvanic isolation at the output. The inverter topology eliminates the need for a DC intermediate voltage by using an AC-link output inverter. This circuit is based on a square-wave cycloconverter combined with a simple new control approach to produce a "PWM cycloconverter" that supports the use of either IGBTs or SCRs to further reduce the system cost.