Role of Grid Topology in Power Quality Improvement of Solar-Powered Electric Vehicle Charging Station

Conventional approaches for designing and integrating charging stations into the grid are time-consuming and computationally expensive. For the purpose of power quality enhancement of EVCS, more focus has been paid on charging station design infrastructure, hence neglecting the need for the technical design of grid topology. Therefore, this paper focuses on the design and development of multiple distribution grid topologies for topology-aware characterization of power quality in grid-tied solar-powered EV charging stations. The control and energy management strategy is implemented solely to enable consistent grid-PV-EV interaction. The models have been successfully developed and tested for four modes of operations, PV to EV, PV to Grid, V2G and G2V, in MATLAB/Simulink 2022b. From the results, it is clear that the grid voltage THD during V2G remains at 0.01%, 0.08% and 0.01% and the grid-connected current THD remains at 0.19%, 1.88% and 0.19% for three different grid topologies, GT1, GT2 and GT3, respectively, while, during G2V, the voltage THD are valued at 0.02%, 0.05% and 0.03% and the grid-connected current THD at 0.45%, 1.28% and 0.75% for grid topologies GT1, GT2 and GT3 respectively. The results demonstrate that grid topology-aware analysis is required for consistent harmonic characterization of PV-integrated EV charging stations under V2G, G2V and PV-assisted operating modes.