Solid Oxide Fuel Cell with DC-DC Converter System: Control and Grid Interfacing

摘要

Fuel cell unit generally has low voltage DC as output. To increase the output voltage, fuel cell stack is used where number of single unit fuel cell are connected in series or parallel. To step-up or step-down the output voltage of solid oxide fuel cell (SOFC), DC-DC converter is used. The DC output voltage of the converter is converted to AC with the help of DC-AC inverter. This paper develops MATLAB/Simulink model of fuel cell based power system (FCPS) comprising of fuel cell stack, DC-DC converter and DC-AC inverter. Sliding mode control (SMC) scheme is implemented in DC-DC buck converter, which guarantees stable output voltage despite transient variations in output voltage of fuel cell. Hysteresis current controller (HCC) scheme is implemented in DC-AC inverter which enables the fuel cell stack to supply utility AC voltage to grid and other power applications.