Simulation Analysis of Relay Protection Action Adaptability under Non-preset Operating Conditions of Complex Large Power Grid
There are many emergencies under non-preset operating conditions,resulting in poor adaptability of relay protection logic and more unreasonable areas,therefore,simulation analysis of relay protection action adaptability under non-preset oper-ating conditions of complex large power grid is carried out.This paper analyzes historical conventional faults,mark the most common location of fault points,builds zero sequence and negative sequence directional element models,distance element mod-els and longitudinal current differential element models,observes the changes of power grid parameters under non-preset oper-ating conditions of complex large power grid,master the coupling of power grid at the first time,constantly select the relay protection action logic required by power grid,and confirm the adaptability of relay protection action.Simulation experiments show that if the fault point is set in and out of the protection area,the relay protection action can select different protection models according to the fault to cut the fault bus or protection no action,which has good adaptability.
complex large power gridnon-preset operating conditionfault predictionelement model constructionrelay pro-tection