Open AccessFault direction identification for wind power integration system
Author(s) -
Chen Yu,
Wen Minghao,
Hu Liexiang,
Qi Xuanwei,
Zheng Junchao,
Wang Zhen
Publication year - 2019
Publication title -
the journal of engineering
Language(s) - English
Resource type - Journals
ISSN - 2051-3305
DOI - 10.1049/joe.2018.8802
Subject(s) - fault (geology) , voltage , fault indicator , frequency domain , electric power transmission , control theory (sociology) , engineering , transmission line , electric power system , stuck at fault , time domain , wind power , power (physics) , computer science , electronic engineering , fault detection and isolation , electrical engineering , physics , artificial intelligence , control (management) , quantum mechanics , seismology , geology , actuator , computer vision
Traditional directional relays of AC transmission lines are usually based on 50 Hz information in frequency domain in China. However, this conventional approach cannot provide the correct fault direction for the lines connected to wind farm because of the fault characteristics of the wind power system, that is, frequency deviation, variation of system impedance, weak feed feature, and so on. Then, the conventional approach of finding the phase angle between the fault current and a voltage signal will not identify the correct fault direction. To solve this problem, this paper proposes a novel fault direction identification method in time domain. Based on the RL model of transmission lines, opposite‐side voltages of the line can be derived with the measuring current and voltage at wind farm terminal after the fault. Then, the adjusted cosine similarity between the calculation voltage based on the RL model and the memory voltage can be acquired. If the correlation between the calculation voltage and the memory voltage is close to 1, it is a reverse fault. Otherwise, it is a forward fault. Finally, the proposed novel fault direction identification criterion is verified by the PSCAD/EMTDC‐based simulation results.