Frequency Regulation by Decentralized V2G Control with Consensus-Based SOC Synchronization

Abstract

Abstract Penetration of Intermittent Renewable Energy Sources (IRES) into power systems disturbs supply-demand balancing in short time period within 20 minutes and deteriorates frequency stability since IRES output depends on a weather condition. This paper proposes a novel decentralized Vehicle-to-Grid (V2G) system that contributes to improve a performance of Load Frequency Control (LFC). In order to avoid a biased use of specified Electric Vehicle (EV) batteries, the outputs of EV batteries are controlled so that State Of Charge (SOC) of all EVs are synchronized. The design of the decentralized control is based on Average Consensus Algorithm (ACA) that enables distributed agents to share the average value of common state variable by only direct communication among neighboring agents. The agents installed in EV chargers control charge/discharge power of the EV batteries so that their SOCs are synchronized based on the shared information of an average SOC. Performance of the proposed method is evaluated by time-domain simulations based on a model of a large scale single-area power system in which a large amount of EV are assumed to be penetrated.