Load following capability of fuel cell-microturbine based hybrid energy system for microgrid operation

Proton Exchange Membrane Fuel Cells (PEMFC) show great potential as a distributed generator in microgrid applications. However, physical constraints impinge PEMFC to follow rapid load following and often requires a supplementary energy storage such as battery or a supercapacitor for such assistance. This paper proposes MicroTurbine (MT) as an alternative over battery or supercapacitor based energy storage, to be used, not only to meet the transient part of the load but also the steady state. Proper, electrical and thermal integration of PEMFC and MT is critical for its successful implementation and industry acceptance. This paper focuses on the electrical integration of the systems and presents simple control strategies for load following operations in autonomous and grid connected modes. Controllers are designed using conventional loop gain technique. Both PEMFC and MT are modeled in MATLAB/Simulink environment. Simulation results verify the effectiveness of the designed controllers under both the modes of operation.