A fuzzy logic approach for fault diagnosis and recovery in PHEV and EV chargers

This paper presents a fuzzy-logic approach for fault diagnosis in a plug-in hybrid electric vehicle (PHEV) or electric vehicle (EV) charger. The approach correlates faults and basic measurements then utilizes fuzzy logic to diagnose a fault. Redundancy is engaged as needed based on the fuzzy logic decision. Experimental validation is first shown for the converter model. Then, a fuzzy system is developed based on correlation of faults and measurements. Faults considered are open-circuit and short-circuit faults in major components. Results show that all faults are accurately detected even though two pairs of faults are confused and are thus both flagged. Design of the fault diagnosis method is shown to be simple and can be applied to a wide array of energy systems.