A linear quadratic regulator control of a stand-alone PEM fuelcell power plant

This paper introduces a technique based on linear quadratic regulator （LQR） to control the output voltage at the load point versus load variation from a stand- alone proton exchange membrane （PEM） fuel cell power plant （FCPP） for a group housing use. The controller modifies the optimal gains ki by minimizing a cost function, and the phase angle of the AC output voltage to control the active and reactive power output from an FCPP to match the terminal load. The control actions are based on feedback signals from the terminal load, output voltage and fuel cell feedback current. The topology chosen for the simulation consists of a 45 kW proton exchange membrane fuel cell （PEMFC）, boost type DC/ DC converter, a three-phase DC/AC inverter followed by an LC filter. Simulation results show that the proposed control strategy operated at low commutation frequency （2 kHz） offers good performances versus load variations with low total harmonic distortions （THD）, which is very useful for high power applications.