Evaluation of electric vehicle charging controllability for provision of time critical grid services

Replacement of conventional generation by more stochastic renewable generation sources leads to reduction of inertia and controllability in the power system. This introduces the need for more dynamic regulation services. These faster services could potentially be provided by the growing number of electric vehicles. EVs are a fast responding energy resource with high availability. This work evaluates and experimentally shows the limits of EV charging controllability using widely supported IEC 61851 standard. The focus is put on EVs suitability for providing ancillary grid services with time critical requirements. Three different series produced EVs are tested. The experimental testing is done by using charging current controllability of built-in AC charger to provide a primary frequency regulation service with very dynamic input frequency. The results show that the controllability of most EVs is more than suitable for providing time critical grid services. Meanwhile, charging current ramping rates of recently produced EVs are potentially suitable to even provide synthetic inertia.