Probabilistic modeling of EV charging and its impact on distribution transformer loss of life

The effect of uncontrolled electric vehicle (EV) charging on the distribution side is considerable and has the potential to affect the life of distribution components. This especially has significant impact on secondary-distribution transformers in residential zones. With smart grid implementation, assessment for reliability of feeder-level components becomes more crucial. This work analyzes the distribution-level secondary transformer loss of life as the result of EV charging. Different charging patterns are developed using a probabilistic model for vehicle arrival time and charge left at arrival. A number of different scenarios, such as residential loading, weather patterns, and geographical locations, are considered in analyzing the effects.