Optimal Placement of Electric Vehicle Charging Stations in Active Distribution System /

Abstract

Electrification of transportation sector can play a vital role in reshaping smart cities. With increasing number of electric vehicles (EVs) on the road, deployment of well-planned and efficient charging infrastructure is highly desirable. Unlike level 1 and level 2 charging stations, level 3 chargers are super-fast in charging EVs. However, their installation at every possible site is not techno-economically justifiable as due to their high power consumption, level 3 chargers may cause violation of critical system parameters. In this paper, we demonstrate an optimized combination of all three types of EV chargers for efficiently managing the EV load while minimizing installation cost, losses, and transformer loading. Photovoltaic (PV) generation is also incorporated in the analysis. Due to uncertain nature of vehicle users, EV load is modelled as a stochastic process. Particle swarm optimization (PSO) is used to solve the constrained nonlinear stochastic problem. MATLAB and OpenDSS are used to simulate the model. Proposed idea is validated on real distribution system of National University of Science and Technology (NUST) Pakistan. Results show that an optimized combination of chargers placed at judicious locations can greatly reduce cost, losses and distribution transformer congestion while meeting EV load demand in an active distribution system. It is also realized that integration of PV improves voltage profile and reduces the negative impact of EV load. Our optimization model can work for commercial areas such as offices, university campuses, and industries as well as residential colonies.