Voltage performance enhancement of DFIG-based wind farms integrated in large-scale power systems: Coordinated AVR and PSS

According to large extension of Doubly-fed induction generators (DFIGs) in power systems, providing appropriate operating condition for this type of wind technology in fault situations seems necessary. Among the essential requirements for DFIGs in fault situations, low-voltage ride-through (LVRT) capability is the utmost important issue. This paper deals with voltage performance enhancement of DFIG-based wind farms integrated in large-scale power systems under voltage dips. This aim is satisfied by create coordination between automatic voltage regulator (AVR) and power system stabilizer (PSS) of synchronous generators. In this research, the key tool for the coordination is fuzzy logic. The necessity of coordination for the designed fuzzy controller (fuzzy coordinator) is to eradicate destructive interactions between AVR and PSS in grid disturbance conditions. The fuzzy coordinator adjusts the AVR and PSS gains to enforce them to give the best performance in fault situations. The proposed coordination supports the voltage mitigation in the Point of common coupling (PCC) under voltage dips and decreases the reactive power requirement of the DFIGs. The performance of the designed fuzzy coordinator is demonstrated on the IEEE 10-machine 39-bus power system with different levels of DFIG-based wind farms contribution. (C) 2015 Elsevier Ltd. All rights reserved.