An intelligent control method for capacity reduction of power flow controller in electrical railway grids

Abstract

Adoption of smart grids has led to significant opportunities in the optimal operation of systems and energy consumption in utility grid loads. Among the various grid loads, electrical railway networks (ERNs) are known as one of the most important and critical end users due to their high power consumption. Energy management and power quality domination in such a network are already concerns of researchers. The railway power flow controller (RPFC) is a commonly used system to manage the optimal energy consumption and power quality problems of ERNs. This paper presents a comprehensive study of an RPFC power rating and a new compensation strategy with the objective of reducing the installed capacity in several consecutive traction power substations (TPSs). This technique is implemented through the use of a Yd transformer with multiple phase connections and the central Steinmetz-based intelligent control system (SICS). Through coordination with the internal control systems, the optimal mode of the active and reactive powers transferring in different phases is calculated by the central SICs and applied to each TPS. The proposed control strategy substantially diminishes the RPFC converter’s power rating and installation costs. A real-time laboratory platform for the smart-grid based proposed method is provided using Opal-RT emulator to confirm the theoretical analysis with the desired precision representing the real power system behavior.