Performance-based settlement of frequency regulation for electric vehicle aggregators

Vehicle-to-grid (V2G) aggregators may have an uncertain capacity submission problem due to random behaviors of pertaining EVs. From the market perspective, we investigate whether the market settlement rules are appropriate enough to induce V2G aggregators to submit an accurate capacity rather than an exaggerated over-capacity. We first review the frequency regulation settlement rules of most representative ISOs in North America such as PJM, MISO, CAISO, and NYISO and several European TSOs. Based on the settlement rules, we analyze how the uncertain submission of V2G aggregators affects the settlements in terms of mileage and accuracy, and perform simulations to evaluate the effect of the exaggerated over-capacity submission on mileage, accuracy, and reward. Through simulations, we show that the conventional frequency regulation settlements fail to induce V2G aggregators to estimate accurate achievable power capacity. To solve this problem, we propose to enhance the accuracy of performance in settlement. We deal with the effect of delay and stochastic properties on payments.