A coordinated CVR-EVDC approach for electric vehicle charging demand management

This paper presents a novel coordinated Conservation Voltage Reduction (CVR) and Electric Vehicle Demand Control (EVDC) method for energy-efficient power system operation. The goal of coordinated CVR-EVDC is to minimise the total energy consumed by the distribution network through coordination of the scheduling of EV charging, the OLTC transformer tap position, and the switching of the capacitors on the network. Using publicly available statistics of journey length and travel time of car drivers in the UK, a stochastic model is developed for EV battery State-of-Charge (SOC) and its availability for home charging to generate EV charging demand profiles for different levels of EV penetration. These are then used in conjunction with Particle Swarm Optimisation (PSO) and a relaxation equality constraint to explore the potential for optimally coordinating CVR operation and the scheduling of charging of EVs on LV distribution networks. Results for five different LV network scenarios show that a coordinated CVR-EVDC approach enables more significant energy savings than with independent operation of CVR and EVDC – 4% greater with dumb charging and 3% greater with valley-filling smart charging. This study shows that distribution network operators can manage the networks by coordinating CVR and EVDC to manage consumer charging requirements for better energy savings.