Coordinated Frequency Control Strategy for Electric Vehicles and Air Conditioners Based on Hierarchical Control Scheme

摘要

The large-scale access of renewable energy brings severe challenges to the stability of power grid’s frequency. Flexible loads which can participate in frequency regulation (FR) provides a new solution for power grid to solve this problem. Therefore, this paper proposes a coordinated control strategy of electric vehicles (EVs) and air conditioners (ACs) based on hierarchical control scheme. The upper layer of the hierarchical control scheme focuses on the coordination of different load aggregators of EVs and ACs. According to loads’ different response characteristics, a refined state classification method is proposed to calculate each aggregator’s controllable capacity accurately. The lower layer concentrates on the capacity allocation between individual loads in the cluster, and the unified model of loads of different parameters is used to determine loads’ action priority. Simulation results show that the proposed strategy can satisfy the users’ needs and the power grid’s FR requirements to the maximum extent, and the effectiveness of the strategy is verified.