Comparing different EV charging strategies in liberalized power systems

Electric vehicles (EVs) can be an important building block of future power systems due to the flexibility of the charging process. In liberalized power systems, the objectives of using this flexibility vary for different actors in the system. In this paper we formulate the optimization problem of EV charging from the perspective of three different actors: 1) consumers (represented by an aggregator), 2) distribution network operators and 3) wind power producers. The respective objectives of these actors can be summarized as minimizing charge costs, minimizing network losses and maximizing profits on a day-ahead market. The results show that the three different perspectives lead to markedly different EV demand profiles. These differences are partly caused by the fact that, due to its stochastic nature, wind power generation weakens the correlation between electricity prices, network load and imbalance volumes.