Paper Title
An Improved Performance of the DPFC During Series Converter Failure By Using Supplementary Control Scheme

Nowadays the demand for electric utilization is goes on increasing due to rapid increase in population. The controlling of the power flow within the interconnected power system is needed. There are so many conventional power flow controlling devices are needed to improve the performance of the power system network. Distributed power flow controller is one of the combined controlled FACTS devices. The DPFC consist of two types of converters. One is series converter and another one is shunt converter connected to grids. The active power exchange between the converters is carried out through the transmission line at the 3rd order harmonic frequency. The redundancy of series converter provides high reliability of the system.In this paper the performance of the DPFC during single series converter failure is considered. An adaptive control scheme to improve the performance of the DPFC during the single series converter failure is proposed. The method of control is based on the failure of single series converter will lead to unsymmetrical current components at the fundamental frequency. The failure of the series converter is compensated by controlling the negative and zero sequence currents to zero. The main advantages of the proposed control scheme are to provide the continuity of the supply between the buses, eliminate the sequential components of currents within the line and continuity of active power exchange between series and shunt converters is maintained. The system is simulated on MATLAB environment and results are presented to highlight the effectiveness of the proposed control scheme. Keywords- Power flow control, flexible AC transmission system, symmetrical components, 3rdharmonic frequency, reliability, transmission system,