Study on Energy Management Strategy for Reducing Equivalent Hydrogen Consumption in a Combined Heat and Power System Based on PEMFC

Combined heat and power (CHP) system based on proton exchange membrane fuel cells (PEMFC) can improve the overall efficiency by recycling the heat generated within the electrochemical reaction process of H2, which is a potential, environmentally friendly and efficient co-production mode. Due to the soft output characteristics of fuel cells, it is always equipped with auxiliary power equipment as a hybrid energy system. A number of studies have been carried out on the energy and efficiency analysis of CHP. However, few people pay attention to the energy distribution strategy and its effect on hydrogen consumption in real application scenarios. In this work, a 10kW PEMFC CHP system and the corresponding simulation model were built based on the energy demands of a family, and the model was verified by the measured data. Under the electric-following operation mode in the off-grid scenario, the minimum equivalent H2 consumption were optimized by the follow strategy, compound fuzzy logic control strategy (Compound-FLC), genetic algorithm optimized FLC (GA-FLC) and energy strategy based on Pontriagin's minimum principle (PMP). The results show that the equivalent H2 consumption of CHP has been significantly improved by GA-FLC, and the state of charge (SOC) of the battery are relatively stable. PMP strategy can further reduce the equivalent H2 consumption and the operating cost by 4.22% and 4.17%, respectively, compared with the follow strategy. The strategy proposed in this paper can effectively improve the economy of PEMFC-CHP system.