Grid-interfacing Fuel Cell system with active and reactive power flow control

This paper deals with the design, analysis, modeling and control of Power Conditioning Unit interfacing the Fuel Cell to the Utility Grid with proper power flow control. The output of the Fuel Cell Stack is connected to the DC side of the Voltage Source Inverter for interfacing to the Grid. The active power transfer is based on the phase angle between DC-AC converter output voltage and Grid voltage and reactive power management is based on magnitude of these voltages. The designed control scheme of the inverter consists of a cascade of two independent controllers, where the external PI power controllers generates the reference currents that is tracked by the inner hysteresis current controllers which generates the pulses for the inverter switches. The entire system is modeled in MATLAB/Simulink environment and simulations carried out to verify the operation and the control principle. Various simulation results are presented for the proposed Fuel Cell Grid interfaced system.