Application of Unified Power Flow Controller to Improve the Performance of Wind Energy Conversion System

This research introduces the unified power flow controller (UPFC) as a means to improve the overall performance of wind energy conversion system (WECS) through the development of an appropriate control algorithm. Also, application of the proposed UPFC control algorithm has been extended in this research to overcome some problems associated with the internal faults associated with WECS- voltage source converter (VSC), such as miss-fire, fire-through and dc-link faults

Application of UPFC to Improve the LVRT Capability of Wind Turbine Generator

Variable speed wind turbine generators installation has been significantly increased worldwide in the last few years. Voltage sag at the grid side may call for the disconnection of the wind turbine from the grid as under such faults it may not comply with the recent developed grid codes for wind energy conversion systems (WECS). In this paper, a Unified Power Flow Controller (UPFC) is applied to improve the low voltage ride through (LVRT) capability of doubly fed induction generator (DFIG)-based WECS during voltage sag at the grid side. Simulation is carried out using MATLAB/Simulink software. Results show that UPFC can significantly improve the LVRT capability of DFIG-based WECS and hence maintaining wind turbine connection to the grid during certain levels of voltage sag at the grid side

Application of STATCOM-HTS to Improve DFIG Performance and FRT during IGBT Short Circuit

A little attention has been paid to the faults within the converter switches of a wind energy conversion system (WECS). Solutions suggested in the literature to improve the performance of a WECS rely on compensating the reactive power at the point of common coupling (PCC) to maintain the PCC voltage within the limits specified by the grid codes. Recently, transmission line operators have expanded WECS codes to include active power support to the grid during fault conditions. Therefore, to maintain the connection of a wind turbine during various disturbance events, it is essential to fulfil grid codes. This paper introduces a new application for a static synchronous compensator (STATCOM) equipped with a high-temperature superconducting coil (HTS) to compensate both active and reactive powers at the PCC during short-circuit events within the insulated-gate bipolar transistor (IGBT) switches of the grid side converter (GSC) of a doubly-fed induction generator (DFIG)-based WECS. Compliance of the voltage profiles of the DFIG with the fault ride-through (FRT) specified in the recent grid codes of the USA, and Spain, with and without the proposed controller, is examined. Simulation results show that the proposed controller can bring the active and reactive power at the PCC to their nominal steady-state levels during studied fault