Design and Implementation of a PWM Rectifier - Based VSC - HVDC System for Enhanced Reactive Power Management and Grid Stability

Abstract

The Advanced AC-DC conversion techniques are required due to the growing demand for high power quality and efficient power conversion in contemporary electrical systems. Poor power factor, high harmonic distortion, and restricted power flow control are common problems with conventional rectifiers. This work proposes a three-phase AC–DC conversion system with an enhanced control strategy to overcome these difficulties. The three-phase AC input is converted into a steady DC output using a Pulse Width Modulation (PWM) rectifier, and current ripples are minimized by source inductance. While DQ-axis control allows independent control of active and reactive power, a closed-loop Proportional Integral (PI) controller keeps the DC-link voltage at intended reference level. Synchronous switching pulses are created by processing the control signals via a PWM generator and driver circuit. The experimental results show consistent voltage output, low distortion, and stable operation with less ripple. For High Voltage Direct Current (HVDC) and energy storage applications, the proposed approach achieves a power factor of 1%, surpassing current techniques (1.6% and 1.2%), ensuring increased efficiency, improved power quality, and dependable performance.