Impedance-based fault location methods for transmission line connecting wind farm plants

With an increasing capacity of wind power installed in the world, the impact of wind generation during fault condition has been studied. Wind plants equipped with induction generator results in a different fault behavior in transmission networks. In this paper, the validation of existing impedance-based fault location methods are performed on a transmission line connecting wind plant equipped with three different types of induction generators. This work is based on the simulation in real-time digital simulator (RTDS).;Squirrel-cage induction generator (SCIG), wound-rotor induction generator (WRIG) and doubly-fed induction generator (DFIG) are the three common generators used for wind power plants. Therefore, models for these induction generators are developed and the control schemes for each type are simulated to represent a working wind plant. Pitch angle control and variable slip control are applied to SCIG and WRIG respectively to maintain a constant power output of the wind generators. DFIG utilizes vector control strategy to control the power output of the wind generators independently.;After the wind plant model is developed, it is connected to an equivalent transmission line system. A fault is simulated on the transmission line so that the fault location algorithm can be applied to determine the fault location estimation with the existence of wind plant.;Results of fault location estimation are compared and discussed when fault location algorithms are applied to transmission line system connecting different induction generator-based wind plant. It is validated that certain fault location algorithms are not accurate for transmission line connecting wind plant.