Analysis of Electric Vehicles Interfacing with Three-Phase Four-Wire Distribution System

Electric vehicles (EVs) offer several benefits to the grid, such as providing active and reactive power support and frequency regulation services. However, integrating EVs into the power system raises uncertainties for both the grid and EV owners. In order to manage these uncertainties, this paper conducts a comprehensive analysis of a three-phase four-wire system for EVs connected to microgrids. It examines the positive, negative and zero sequence components of voltages and currents, assuming the presence of only grid frequency components and disregarding harmonics. This paper also delves into the behavior of these components under three different scenarios, equal resistance, equal current, and constant power. The main goal of the constant power approach is to align active and reactive power with references, and reduce oscillations in active power.

I. Introduction

The growing adoption of electric vehicles (EVs) presents the opportunity to harness them as controllable power sources and energy storage devices through vehicle-to-grid (V2G) connections. [1]–[3]. By connecting EVs to microgrids and implementing suitable controls, we can reduce the strain on traditional energy resources and decrease carbon emissions [4], [5]. Additionally, using EVs in this way can stabilize voltage and strengthen the grid against potential collapse caused by imbalances in reactive power. However, if EV charging is not well coordinated, high penetration levels (45%) can lead to overloading of transformers and significant power losses in the distribution system. [6]–[9].