A distributed approach for DG integration and power quality management in railway power systems

Abstract

Currently, railway systems are electrified to meet the rising demand for faster speed, more stable operation and more passenger traffic. Although special electrical traction systems are utilized to provide power for railway load consumption, major power quality challenges are present. This paper addresses the Volt/VAR control problem in railway power systems (RPS) considering distributed generations (DGs) interconnected to the system via smart inverters. An economic Volt/VAR sensitivity analysis approach is developed to obtain ideal reactive power injected from DG units. An adaptive energy reserve method is presented, which routes the surplus energy available to the energy storage system (ESS) to be utilized eventually. The problem of decreasing system losses, and maintaining a good voltage profile is formulated as a multi-objective optimization problem. A six-bus system is used for control architecture validation. Simulation results indicate reduction in the technical losses and the stress on automatic voltage regulators. Easy to implement model, without hard to design parameters and high efficiency, highlights the potential aspects for real-life applications.