Improvement of the DPFC performance in Transmission Lines during failure of Series Converter

Abstract

The DPFC is a novel device which is related to FACTS family. It has become visible from the Unified Power Flow Controller. The DPFC is comprised of a shunt converter and a series converter, both interconnected with the grid to regulate power flow. The presence of a common dc link between the shunt and series converters is observed in previous converters such as UPFC. However, in the case of DPFC, the dc link is eliminated. The series controller ensures costeffective high reliability. In this document, we examine the efficiency of DPFC when a single series converter fails, and we also implement a control scheme to enhance DPFC’s performance in such failure scenarios. The control principle relies on the fact that the failure of a single series converter will result in the occurrence of unsymmetrical currents across the entire system. Monitoring the zero and negative sequence currents can help to overcome this failure. A well-suited control scheme has been devised in this study to overcome the challenges arising from the series converter failure and effectively manage the active power, reactive power, grid voltages, and currents. The obtainability of the control scheme and simulation diagrams of DPFC can be achieved through the appropriate design.