A Mixed Active-Passive Algorithm for Islanding Detection of Wind Turbine DG Units

摘要

A new islanding detection algorithm method based on combination of passive and active techniques is presented for wind turbines as distributed resource units at the distribution voltage level. In the first step of the proposed algorithm, the rate of change of output active and reactive power is calculated. If these values exceed a predetermined threshold, the islanding is likely occurred. To verify happening of islanding, capacitor bank of wind turbine is switched and signs out from the system. Islanding is detected by measuring frequency and rms value of load voltage. The detection time of the proposed method is less than IEEE1547 standard. Time-domain simulations in MATLAB are used to verify the performance of the algorithm. The feasibility of the proposed method is also evaluated by an experimental system. The results show that the proposed islanding detection method successfully distinguishes between islanding phenomenon and other switching conditions.