STTR Phase I: Advanced Fuel Cell Energy-Management Electronics and Control for Microgrid

This Small Business Technology Transfer (STTR) PhaseI project will design, fabricate, and validate a novel low cost (under $40/kW), robust and high-power-density 3 kW fuel cell (FC) power-conditioning system (PCS) suitable for lower voltage FC stacks, comprising a high-frequency inverter (HFI) followed by a forced cyclo-converter, which yields the following features: (1) 300 kHz switching frequency and direct power conversion (eliminating intermediate bulk capacitors) leading to 5X (> 15 W/in3) increase in power density as compared to state-of-the-art power technology; (2) line-frequency (60 Hz) switching of the cyclo-converter, thereby practically eliminating switching losses and leading to higher reliability of PCS and efficiency; (3) at least 90% energy efficiency at full load and a high efficiency across the load spectrum; (4) galvanic isolation is achieved between the FC and the load using only a small HF transformer; (5) a novel battery power-management control system, which ensures (6) that under transient load conditions the FC is protected by fast energy buffering; and, (7) eliminates 120 Hz inverter current ripple under steady-state condition without bulky filter, thereby significantly enhancing the life and efficiency of the FC. Two key application areas of FC energy systems are in residential and commercial power systems, where the projected worldwide market is $50 billion by 2015. The application is targeted at this large stationary power system market segments comprising residential and commercial applications. As such, the proposed PES is of prime interest to number of companies.