Design and simulation of a fuel cell power plant with dynamic multi-unit load sharing in grid-connected and grid-isolated modes of operation

Worldwide population has increased exponentially following the First Industrial Revolution. Over two-centuries later and the population has doubled nearly three-fold. Although roughly 15% of the population is without electricity, global energy demand has followed virtually proportional. In the modern power system, energy production is categorized into three main sectors: fossil-fuel, nuclear, and renewables. Renewables is the most rapidly growing sector, nevertheless, the conventional fossil-fuel based method still represents 60% of total production. Growth of capacity via conventional techniques is limited due to increased carbon emission regulation. As a result, renewable energy penetration doubled in the last decade. Relying on environmental conditions, renewable sources are less stable due to their intermittent behavior, therefore grid integration poses a challenging issue. Microgrids, capable of grid-connected and grid-isolated operation, have been widely explored as a viable solution addressing some of these issues.

In this work, the MATLAB/Simulink simulation model of a fuel cell power plant cluster is discussed. Each cluster behaves as an ac microgrid, is modular, operates in both grid-connected and grid-isolated modes, and provides dynamic multi-unit load sharing. Other research has discussed the development of microgrid control algorithms, the seamless transition between different modes of operation, and the impact of power tracking dynamics in fuel cell units. This research aims to further increase the body of knowledge by analyzing the real-reactive power controller, secondary voltage-frequency droop controller, and implementation of the seamless transition between control modes in fuel cell cluster(s) with multiple fuel cell operating points and load transitions. The design criteria and impact of fuel cell VI performance is considered.