Analysis and elimination of the output voltage imbalance for a half-bridge boost rectifier under mismatched loads

The voltage imbalance between the dual output DC voltages of a half-bridge boost rectifier with mismatched loads is analyzed by adopting an averaged circuit model. A compensating signal proportional to the voltage difference is added in the current command to eliminate the voltage imbalance. Also the adverse effects of the compensating current to the input power factor are discussed. Experimental results on a prototype circuit are given to confirm the theoretical analysis.