Abstract :
A unified power flow controller (UPFC) based on the flying capacitor (FC) multilevel voltage-source converter (VSC) topology with phase-shifted sinusoidal pulse-width modulation (PWM) control is presented. This converter allows higher power handling, potentially lower power loss, lower harmonic distortion and hence less filtering requirements when compared with the typical two-level counterpart. The series converter injects a voltage with controlled magnitude and phase, to control the active/reactive power flow in a transmission line. The shunt converter absorbs/ supplies active power demanded by the series converter to maintain a constant DC link voltage, also providing independent reactive support to the network. A complete model of the proposed UPFC system is shown and control circuits are described in the synchronous d-q frame. Finally, simulation results are provided to confirm the robustness of the proposed system
Keywords :
PWM power convertors; capacitors; flexible AC transmission systems; load flow control; reactive power control; active power absorption; active power flow control; active power supply; constant DC link voltage; control circuits; controlled magnitude voltage injection; filtering requirements; flying capacitor multilevel PWM converter based UPFC; flying capacitor multilevel voltage-source converter; higher power handling; independent reactive support; lower harmonic distortion; lower power loss; phase-shifted sinusoidal pulse-width modulation control; reactive power flow control; robustness; series converter; shunt converter; synchronous d-q frame; transmission line;
