Islanding detection of wind farms by THD

Abstract

One of the most main protection requirements of grid connected wind turbines (WTs) is islanding detection and anti-islanding protection. In this paper, a new method for islanding detection of WTs based on THD of asynchronous generator currents is proposed. The new features of the proposed method are its application for wind farms with a large number of wind turbines under noisy windy conditions and appropriate for asynchronous type of wind turbine generators. The proposed method monitors the generator currents and calculates their THD then base on an algorithm the status of the WTs will be detected. The proposed method has been evaluated under different conditions such as load changing, noisy windy conditions, induction motors starting and capacitors switching by using PSCAD/EMTDC software. In this research, data of WTs are according to the real data of V47/Vestas wind turbines working in the Manjil site.