Modeling and control strategy of solid oxide fuel cell generation system

According to the electrochemical character of solid oxide fuel cell (SOFC) and operational requirements of micro grid, the overall model of SOFC power generation system which contains SOFC, BOOST converter, storage battery(BESS), buck-boost converter, DC/AC inverter and filter is developed and the control strategy adapting to various operating status is proposed. DC/AC inverter adopts V/f droop control strategy which includes inner current and outer voltage loops. The controller also incorporates synchronization block for ensuring smooth and safe reconnection from islanding mode to grid-connected mode in micro grid. In order to improve the dynamic response speed of SOFC, storage battery is in parallel with DC bus through buck-boost converter which adopts hysteresis charging/discharging control strategy to raise the power regulation speed. The structure of micro gird which contains SOFC power generation system is set up. The simulation results of SOFC generation system operating on grid-connected mode, islandi