On large action space in EV charging scheduling optimization

Abstract

In order to reduce the air pollution by traditional fossil fuel and save the charging cost, much attention has been paid to the charging scheduling of electric vehicles (EVs) in the uncertain supplement of wind power and solar power. Owing to the randomness in the renewable power generation and the EV charging demand, simulation-based policy improvement (SBPI) has been well adopted for making charging decision. However, it is challenging to explore the large action space which grows exponentially with respect to the system scale. We consider this important problem in this paper and make the following contributions. First, we explore the structural property of the problem and develop an urgency index to rank the EVs. Second, we apply three methods to search in the action space. Third, we numerically demonstrate the performance of the urgency index and the search methods, and compare the SBPI methods with the CPLEX-based method. It shows that SBPI improves the base policies in all these cases.