电力系统保护与控制2025，Vol.53Issue(18)：26-38,13.DOI:10.19783/j.cnki.pspc.240739
负序电流突变下基于动态热能模型的反时限保护曲线修正方案
Correction scheme for inverse time protection curve based on dynamic thermal energy model under negative sequence current sudden change
摘要
Abstract
To address the problem that conventional negative sequence inverse time overcurrent protection for generators cannot accurately characterize the protection's action time after sudden changes in negative sequence current,a correction approach for the negative sequence inverse time overcurrent protection curve based on the dynamic thermal energy model is proposed.First,the generator terminal negative sequence suppression strategy under new energy control and the variation of negative sequence current during unbalanced transmission line operation are analyzed.A negative sequence inverse time overcurrent protection action scheme is proposed to address the three-stage changes of negative sequence current.Then,a dynamic thermal energy model reflecting the rotor temperature is established based on the real-time measurement of negative sequence current,considering the non-periodic component heat generation and convective radiation heat dissipation.Finally,the model is incorporated into the negative sequence inverse time overcurrent protection,where steady-state temperatures of stator and rotor along with preset negative sequence current are used to characterize the negative sequence inverse time overcurrent protection curve.A correction scheme for the protection curve is further proposed that adjusts the curve based on rotor temperature estimated from real-time negative sequence current inputs.Simulation results show that the constructed dynamic thermal energy model can accurately capture rotor temperature,and the proposed curve characterization and correction scheme achieves high accuracy and strong adaptability.关键词
负序反时限保护/负序电流突变/动态热能模型/保护曲线修正Key words
negative sequence inverse time overcurrent protection/negative sequence current sudden change/dynamic thermal energy model/protection curve correction引用本文复制引用
李振兴,安喆,朱益,胡聪,翁汉琍,李振华..负序电流突变下基于动态热能模型的反时限保护曲线修正方案[J].电力系统保护与控制,2025,53(18):26-38,13.基金项目
This work is supported by the National Natural Science Foundation of China(No.52077120). 国家自然科学基金项目资助(52077120) （No.52077120）
