基于抗干扰系数的配电网增强型电流差动保护OA

With the widespread integration of distributed generators,distribution network is altered from simple ra-dial network to multi-terminal active network.This shift has caused a decline in the performance of traditional relay protection methods in distribution network.Consequently,current differential protection is being increasingly adopt-ed in distribution network.However,the characteristics of distribution network,such as multi-source,multi-load branches,and bidirectional power flow,leads to decreased adaptability of traditional current differential protection.To address these problems,this paper analyzes the fault current characteristics of various types of distributed gener-ators and explains the reasons for the decline in adaptability of traditional current differential protection.Based on the amplitude and phase of the current on both sides,the sensitivity compensation coefficient is introduced to en-hance sensitivity of protection.Additionally,considering the non-ideal conditions such as CT saturation an anti-in-terference coefficient based on Hausdorff distance is introduced to improve security of protection.By setting the pa-rameters of these two coefficients appropriately,the performance of current differential protection is enhanced.Based on PSCAD/EMTDC it is demonstrated that the proposed protection can offer superior sensitivity and security compared to traditional differential current protection.