Combining proportional integral and fuzzy logic control strategies to improve performance of energy management of fuel cell electric vehicles
Hegazy Rezk, Ahmed Fathy
Abstract
One of the key famous problems of a fuel cell (FC) is its slow dynamic response: the FC requires significant time to reach a new steady-state condition after a sudden change in the load. Consequently, the addition of supercapacitor and battery storage devices is highly appreciated. The SC will cover the rapid change in load, whereas the battery will supply load dusting deficit periods in the steady state. An energy management strategy (EMS) is highly required to optimize load sharing among SC, FC, and battery. For electric vehicle applications, optimizing hydrogen consumption is one of the most important challenges and an addition to saving the battery life. There are common EMSs, such as PI control and fuzzy logic control (FLC) strategies. PI is characterized by high consumption of hydrogen and high SOC of battery. In contrast, FLC is characterized by low consumption of hydrogen and the final SOC of the battery. Therefore, it is essential to combine both to build a hybrid PIFLC control strategy to acquire the advantages of both FLC and PI control strategies and to avoid high consumption of hydrogen and low SOC of battery. To evaluate the proposed strategy, the common FTP-75 drive cycle has been considered. The results demonstrated the superiority of the hybrid PIFLC strategy. Using the hybrid PIFLC succeeded in increasing the total performance index by 3.43 % and 9.1 %, respectively, compared with PI and FLC.