Power Management for Fuel-Cell Power System Cold Start

Fuel cells are difficult to cold start. This letter proposes a power management control strategy for cold-starting fuel-cell systems. The operation principles of the system´s cold start are analyzed in detail. A battery powers the load through a bidirectional converter at the beginning of the cold-start state. After the fuel cell finishes its self-start, the fuel cell slips in and the battery slips out of the system, and the fuel cell powers the load independently. The appropriate soft-start control strategies for bidirectional and unidirectional converters are proposed in this letter. A 1-kW fuel-cell power system is built in the laboratory, and experimental results are shown to verify the theoretical analysis.