A three-phase DC-DC converter for low and wide input-voltage range application

Output voltage of the fuel cell or Solar cell is often low and varies widely with the load and environmental condition. However, voltage stress of rectifier diodes is high and filter is large in the conventional voltage-source converter. Therefore, a three-phase DC-DC converter for low and wide input-voltage range application is proposed. It can operate at three modes, i.e., three-full-bridge, two-full-bridge, and one-full-bridge modes. Voltage stress of rectifier diodes and filter are reduced. Operating principle of the proposed converter is illustrated. Design guidelines and example are given. Simulation results of a three-phase DC-DC converter verify the theoretical analysis.