Integration of Fuel Cell Technologies in Renewable-Energy-Based Microgrids Optimizing Operational Costs and Durability

Abstract

In this paper, a Model Predictive Control (MPC) approach is proposed to manage a grid-tied hydrogen microgrid <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$(\mu\mbox{G})$</tex-math></inline-formula> . The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu\mbox{G}$</tex-math></inline-formula> testbed is equipped with a 1-kW polymer electrolyte membrane (PEM) electrolyzer and a 1.5-kW PEM fuel cell as main equipment. In particular, we present a formulation that includes the cost of the electricity exported/imported, the aging of the components, and the operational constraints. The control objective is to satisfy user demand, as well as extend the lifespan of expensive equipment, as is the case of the fuel cell or the electrolyzer. <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu\mbox{G}$</tex-math></inline-formula> performance is investigated under realistic scenarios in three experiments. The experimental results illustrate how the proposed control system is able to manage the fuel cell and the electrolyzer through smooth power references, as well as to satisfy the power demanded. Finally, benchmarking is carried out between hysteresis band (HB) control and the proposed MPC in regard to efficiency and cost of the operation. The results obtained show that the MPC approach is more effective than HB for this type of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu\mbox{G}$</tex-math></inline-formula> , with a reduction in operation cost of up to 30%.