Modeling and simulation of a power conditioning system for the hybrid fuel-cell/turbine power plant

Power conditioning system is an interface between distributed generation and utility grid. This paper presents the model of a power conditioning system (PCS) for the hybrid direct fuel-cell/turbine (DFC/T) power plant. It regulates voltage, current and power transmitted from the hybrid DFC/T power plant to utility grid. The proposed system consists of DC/DC converters, a grid-connected SPWM DC/AC inverter, and an LCL filter. To regulate and stabilize the DC link voltage, DC/DC converter with PI controller is adopted. With the dual-loop PI based grid-connected SPWM inverter, both active and reactive power transmitted to utility grid from the hybrid DFC/T power plant can be controlled. The LCL filter can greatly reduce the current harmonic distortion (THD). Theoretical analysis, modeling methodologies and control schemes are presented. The whole model was developed in Matlab/Simulink environment with all the parameters given. Simulation results demonstrate that the proposed PCS can follow a dynamic load with the error less than 1% and reduce the THD to 1.65%.