Dynamic modelling and control of a shunt-series power flow controller based on AC-link

This study presents the dynamic modelling and proposes two control strategies for an AC-link shunt-series power flow controller (ShSPFC) based on a class of matrix converter termed vector switching converter (VeSC). This topology is intended for regulating the power flow between two buses in a power system by synthesising an adjustable voltage inserted in series to the transmission line. The study includes the principle of operation of this topology and a detailed modelling in abc and dq coordinates. Based on the dynamic model two control strategies are proposed: (i) a classical proportional integral (PI) approach and (ii) an alternative controller based on feedback linearisation (FL). These control algorithms have been compared in detailed via simulations using a benchmark power system. Results include a comprehensive analysis of the transient response owing to step changes in the reference signals and the impact on the power quality.