Fuel cell based Microgrid with NSC Control Strategy

Abstract

Now a day, fuel-cell (FC) based independent sustainable generation network development have gained much interest, due to their low emissions and higher energy-conversion efficiency than traditional methods. Hydrogen energy generation combined with FC is a better alternative because it is a clean and cost-effective source of power generation. A microgrid is a sustainable framework that combines non-renewable and renewable power sources for continued power supply to the load. However, the integration of a hydrogen energy source into a microgrid system shows some technical issues such as fluctuations and increased harmonics in system voltage and currents. Maintaining system stability in this case of uncertainties in the power availability and changing loads has become a major obstacle. This paper proposes an alternative for microgrid system with an improved topological arrangement which is interfaced using a nine-switch converter (NSC) with a fuel cell system and a conventional grid. A 30kW proton exchange membrane fuel-cell (PEMFC) stack has been developed in this paper. The NSC has two different control structures, grid side power control & load side power control. The proposed system is advantageous as it supplies uninterrupted power to the load regardless of the grid side or source side disturbances. Also, no extra switching of the control logic is needed while grid disconnection. The whole system is validated using OPAL-RT 4510 real time simulator and the outputs are presented in this work.