Integrated Linear Transformer-Based Diode Bridge Rectifier for Improved Power Quality in Electric Vehicle Charging Stations

Electric vehicle (EV) charging stations are becoming increasingly widespread, but their front-end rectifiers often degrade grid power quality by introducing high-input current harmonics, a low power factor, and voltage distortion. Although conventional diode bridge rectifiers (DBRs) are simple and low-cost, they typically exhibit total harmonic distortion (THD) exceeding 25% and power factors below 0.80. To address these issues, active power factor correction (PFC) techniques have been employed in the literature; however, they increase system complexity, cost, and control algorithm sophistication. Thus, this paper proposes a linear integrated transformer (ILT)-based DBR, which is designed to improve power quality in EV charging stations without relying on active control mechanisms. The proposed configuration integrates a linear transformer, passive filter network, and diode bridge to achieve both voltage step-down with galvanic isolation and harmonic mitigation in a single structure. This system offers improved voltage regulation, flux balancing, filter resonance, and reduced current distortion. The proposed system is validated using MATLAB/Simulink R2021a. The results demonstrate that it achieves a THD of 4.32%, complying with IEEE 519 harmonic standards. In addition, the input power factor improves to 0.981. The system also reduces the DC output voltage ripple from 6.8% to 1.2%, enhances voltage regulation by 9.1%, and increases overall efficiency to 96.3%. These findings establish the proposed ILT-DBR as an affordable, robust, and compact solution for next-generation EV charging infrastructure, specifically designed to meet the needs of smart grid deployment and integration in Tier-2 and Tier-3 cities, where simplicity and power quality compliance are priorities.