Grid-side converter control of DFIG wind turbines to enhance power quality of distribution network

Abstract

A Doubly Fed Induction Generator Wind Turbine (DFIG-WT) with FACTS capabilities is presented. It is suggested to make use of the grid-side converter as a shunt active filter in order to support the grid with power factor correction as well as harmonic compensation. A vector control scheme is used to control the grid-side converter with a priority level feature to split extra room for compensation. It allows the grid-side converter to be remote-controlled and provide power quality support at a specific point away from the wind turbines plant. No harmonics are injected into the generator and the system is fully operational even at zero output power from the DFIG-WT. Simulation results illustrate good performance of the proposed system.Index Terms--Wind power generation, active filter, doublyfed induction generator, power quality, grid-side converter control.

Impacts of High Penetration of DFIG Wind Turbines on Rotor Angle Stability of Power Systems

“…However, it can regulate the reactive power that GSC can exchange with the grid and can be used as a reactive power support [28].…”

Disturbances Rejection and Harmonics Reduction of Doubly Fed Induction Generator Based Wind Energy Conversion Systems

“…(14), the active power of the system can be found as Eq. (18). The active power that is generated by harmonics can be subdivided into two parts.…”

“…However, to expand the region on the Weibull graph, where the GSC can perform power quality compensating perfectly, and to be assured of its perfect performance, it is better to derate the GSC somewhat. Since only harmonic components are compensated by the GSC, it certainly does not need derating as much as in [7,18].…”

“…To address this subject, some authors have proposed using rotor-side converter (RSC) for the DFIG to compensate harmonic currents of the grid [16,17], but injecting harmonics to the DFIG rotor is harmful for the machine and deteriorates its performance. Some other authors have used a grid-side converter (GSC) for the same purpose [18,19], but since most of the DFIGbased WECSs are connected to grid by a long transmission line, using a GSC for the DFIG to compensate non-linear loads of the grid not only does not improve the situation, it also aggravates it by generating harmonic voltages and may cause some problems for the WECS itself that affect its performance. The harmonics that are generated by the DFIG itself was addressed in [20], but this work did not deal with disturbances imposed by grid harmonics.…”

Simulation and Comparison of Control Methods of Doubly Fed Induction Generator in Energy Conversion System

“…Nowadays, the use of DFIG is ideal due to flexibility, strength and being multi-capacity; thus, it becomes one of the most applicable methods for utilization of wind energy. In spite of the presence of networks connected to wind energy conversion system (WECS) working according to DFIG technology, it still confronts with various challenges such as stability of the system, the quality of power (Nunes et al, 2004), (Tremblay et al, 2006), low voltage, currency errors, phase imbalance (Xiang et al, 2006) and Maximum Power Point Tracker (MPPT) (Shen et al, 2009). Anyway, the point that should be considered is to control the device by itself.…”