Impact of Distributed Power Flow Controller to Improve Power Quality Based on Synchronous Reference Frame Method

Modern power utilities have to respond to a number of challenges such as growth of electricity demand specially in non-linear loads in power grids, consequently, some policies about the power with a higher quality should be considered. In this paper, distributed power flow controller (DPFC) which is similar to unified power flow controller (UPFC) in structure, is used to mitigate the voltage sag and swell as a power quality issue. Unlike UPFC, the common dc-link in DPFC, between the shunt and series converters is eliminated and three-phase series converter is divided to several single-phase series distributed converters through the transmission line. Also to detect the voltage sags and determine the three single-phase reference voltages of DPFC, the synchronous reference frame method is proposed. Application of DPFC in power quality enhancement is simulated in Matlab/Simulink environment which show the effectiveness of the proposed structure.