Suonan Jiale1£¬Zhang Jiankang2£¬Song Guobing1£¬Tursun Ibralayim3
(1.School of Electrical Engineering,Xi'an Jiaotong University,Xi'an 710049,China; 2.Northwest Electric Power Dispatching and Communication Bureau,Xi'an 710048,China;3.School of Electrical Engineering,Xinjiang University,Urumchi 830000,China)
Abstract£ºThe reliability and sensitivity of the present adaptive current protection is dropped under phase-to-phase fault due to the existence of load current in non-valid grounded power systems£®This paper presents a new algorithm£¬which can take into account of the impact of load current under phase-to-phase fault,and can convert the measured phase-to-phase fault current to the three-phase fault current at the same fault point,then the three-phase fault current is used to compare with the setting value.This method ensures the same class of sensitivity for three-phase short circuit and phase-to-phase short circuit,and the simulation verifies the flexibility and reliability£®
Keywords:adaptive current protection;load current;sensitivity