Towards Safe, Stable, and High-Performance Grid Integration of EV Charging Using Power Converter

Abstract

The rapid advancement of electric vehicles (EVs) has intensified the need for efficient power electronics, particularly in the performance of battery charging converters, grid reliability, and system safety. This study provides a comparative analysis of two widely used DC-DC converter topologies—Buck-Boost and Cuk—focusing on their influence on total harmonic distortion (THD), input power factor (IPF), and overall energy conversion efficiency. MATLAB simulations were conducted to evaluate both converters under step-up and step-down operating conditions. In step-up mode, Buck-Boost and Cuk converters achieved efficiencies of 97.72% and 92.93%, respectively. In step-down mode, performance improved slightly, with efficiencies reaching 97.81% for Buck-Boost and 94.87% for Cuk. THD values were notably lower in step-down operation—28.9% for Buck-Boost and 23.1% for Cuk—compared to 29.4% and 24.3% in step-up. Similarly, the input power factor was better in step-down mode, recorded at 81.63% (Buck-Boost) and 90.47% (Cuk), slightly higher than in step-up mode (81.58% and 88.93%, respectively). To assess grid-level implications, the converters were tested in a simulation using the IEEE 13-node test feeder in the DIgSILENT PowerFactory/MATLAB environment. This provided insights into their impact on distribution network behavior. Additionally, engineering concerns such as thermal management and switching losses were examined, as they are vital for long-term system stability and battery longevity. The study not only benchmarks converter performance but also outlines future directions, including improved switching strategies, size reduction, and integration with Vehicle-to-Grid (V2G) systems.