Performance of grid interfaced doubly fed induction generator-wind turbine using fuzzy logic controller based on Gauss Newton algorithm under symmetrical and asymmetrical faults

Abstract

Recently, Doubly Fed Induction Generators (DFIGs) are used in wind power generation due to its popularity for several reasons (a) variable speed wind operation and (b) cost effectiveness. However, when faults occur on power grid, the machine shows sensitivity. To sustain stability of system, high value of DC-link voltage is needed during unbalanced operation of grid. This paper proposed a novel control strategy for the Grid Side Converter (GSC) of DFIG-based Wind Turbine (WT). According to the new grid codes the WT must be connected to grid during occurrences of faults. In this research work the Gauss-Newton (GN) algorithm is deployed for Fuzzy Logic Controller (FLC) and the system is enabled to control the different parameters (DC-link voltage, active and reactive power) during system disturbances. GN algorithm is an optimization technique for FLC replacing traditional Proportional-Integral (PI) controller. Whenever voltage swells occur on grid, the behavior of system becomes non-linear and the FLC based on GN algorithm is better observed technique. The theoretical modeling is carried out to understand FLC & GN algorithm in Matlab/Simulink. Furthermore, the simulation results demonstrates the effectiveness of the proposed controller.