Energy management strategy for integration of fuel cell-electrolyzer technologies in microgrid

Abstract- Proton exchange membrane technology is proven for stationary application but one of crucial aspect of this technology is its durability which is subjected to the operating conditions i.e. load transients, switch ON/OFF events and idling conditions. Such operating conditions may lead to premature failure of electrolyzer (ELY) and fuel cell (FC). However, transient load variation and rapid switch ON/OFF are unavoidable conditions in microgrid due to erratic variation in the photovoltaic source power during cloudy condition and load transients. Therefore, it is challenging to develop a control (energy management) strategy which can ensure the smooth operation of FC and ELY and achieve the others multi-objectives such as balance in demand and supply, higher energy efficiency, reliability and resiliency. The smooth operations of FC and ELY can be achieved by controlling the rate of change of power during transient operating conditions. Present study is dedicated to energy management system (EMS) of hydrogen storage based microgrid. In present study, photovoltaic (PV) generator is used as primary generator while battery and hydrogen (metal hydride) units are used as energy storage mediums. Different control strategies i.e. model predictive control (MPC), hysteresis band control strategy (HBCS), equivalent consumption and minimization strategy (ECMS) and state machine (SM) are used in proposed EMS. The operating cost of system is found to be 8.79, 8.88, 29.54 and 14.73 USD while efficiency is obtained 79.0%, 80.5%,77.4% and 80.0% in HBCS, MPC, ECMS and SM modes, respectively.