CAJ | 학술논문

发现合于永久故障时三相重合闸时刻对系统暂态电压稳定性有较大影响，并以无穷大、单负荷系统为例研究其原因。在感应电动机动态负荷模型下，考虑故障点位置变化，推导出交流线路从发生三相短路、线路三相跳闸、三相重新合闸于永久故障，到最后的三相断路器跳闸的全过程中，负荷侧母线电压及电磁转矩的变化情况。通过对上述暂态过程中电磁转矩－转差率的变化规律发现，最后一次操作完成后，运行点距离新的稳定平衡点越近，越有利于系统的暂态电压稳定。并结合对实际电网中的仿真结果指出，若在转差率增大的过程中投入重合闸，再次故障产生的减速能量会使转差率继续增大，对系统的暂态电压稳定性将产生不利影响。
발현합우영구고장시삼상중합갑시각대계통잠태전압은정성유교대영향，병이무궁대、단부하계통위례연구기원인。재감응전동궤동태부하모형하，고필고장점위치변화，추도출교류선로종발생삼상단로、선로삼상도갑、삼상중신합갑우영구고장，도최후적삼상단로기도갑적전과정중，부하측모선전압급전자전구적변화정황。통과대상술잠태과정중전자전구－전차솔적변화규률발현，최후일차조작완성후，운행점거리신적은정평형점월근，월유리우계통적잠태전압은정。병결합대실제전망중적방진결과지출，약재전차솔증대적과정중투입중합갑，재차고장산생적감속능량회사전차솔계속증대，대계통적잠태전압은정성장산생불리영향。
The effect of three -phase re -closure time on system’s transient voltage stability is larger when it is reclosed to permanent disturbance.Single load infinite bus system is taken as an example to discuss its mecha-nism.Under inductive motor dynamic load model,voltage of load bus and electromagnetic torque during the whole process from permanent fault occurrence to three -phase breaker tripping,re -closure to permanent fault and till three phase breakers tripping again are calculated and analytic expression of which are derived.By analy-zing the changing of electromagnetic torque to slip ratio,it is discovered that it is beneficial for the transient volt-age stability of the system if the operation point is near the stability balanced point when the last operation has finished.According to the simulation result of actual power grid,it is pointed out that transient voltage stability will decrease if reclosure during the process of slip ratio is increasing.