Comprehensive Power Quality Management Scheme for Low Voltage Distribution Networks Based on BTB-VSC

With the widespread integration of distributed energy sources, electric vehicle charging stations, and nonlinear loads, power quality issues in distribution networks have become increasingly severe, including excessive harmonic currents, three-phase current imbalance, and voltage overlimit problems. In this paper, a flexible interconnected distribution network scheme based on Back-To-Back Voltage Source Converter (BTB-VSC) is proposed, and a comprehensive power quality control method is designed. This method solves the problem of harmonic current and three-phase current imbalance by configuring VSC at the end of the line and using hysteresis control. For the overvoltage problems caused by the excess power from Distributed Generation (DG) integration, a joint active and reactive power control method using VSC is employed, leveraging the capacity of interconnected feeder lines in the flexible interconnection system to effectively mitigate voltage overlimit issues and maximize the DG integration capacity. Additionally, the paper integrates an Energy Storage System (ESS) into the DC side using a DC/DC converter to further enhance the system's voltage regulation capability, providing effective technical support for improving power quality in distribution networks.