Modeling and design of matrix converter based unified power flow controller with implementation of complex vector synchronous frame PI current regulators

As one of the most influential members of Flexible AC Transmission Systems (FACTS), UPFC is capable of both managing power flow and maintaining the stable performance of power systems. This paper firstly demonstrates the topology of a matrix converter based UPFC (MC-UPFC), which outweighs traditional UPFC in power losses, weight, and cost, for MC-UPDC possesses no capacitors in the DC link. Control strategies incorporating decoupling control and space vector modulation (SVM) are applied to control the nine bidirectional switches. However, transient performance in response to the power flow changes is limited due to the dependence of traditional PI current regulators on the synchronous frequency. In this paper, an alternative complex vector synchronous frame PI current regulator is analyzed and implemented in MC-UPFC. Furthermore, the system fault ride-through ability of this complex vector PI regulator-based control scheme is also investigated. This control strategy is validated by the simulation studies on Matlab/Simulink, thereby demonstrating an improved performance of power flow control in both transient and steady states.