Wind Farm Connected Distribution Line Protection using Symmetrical Nature of Mean

Abstract

A new statistical fault detection method is proposed in this paper to detect the faults in the distribution lines connected with wind farms. The approach is designed with the help of symmetrical nature of current signals during normal conditions of the system to detect the faults using the non-linearity segment. For this purpose, statistical mean of 1/4^th cycle of current information is used with shifting window mechanism. The method utilize direct instantaneous signal information reduces the computational burden and increases the speed of the decision. The method is tested on wide class of unsymmetrical and symmetrical faults with different fault parameters. The influence of the location, inception angle and resistance of the faults are simulated to test the efficacy of the proposed method. Further, the investigations of the proposed methods are extended to variable wind system conditions to check the adaptability of the method. All the simulations are carried out on a 25 kV, 9 MW wind farm connected to grid using MATLAB-SIMULINK.