CAJ | 학술논문

通过分析基于稳态信号的有功选线原理,以及该方法影响选线准确率的原因,提出了一种消除不平衡电流的零序有功选线新方法.该方法通过算法消除电网不平衡电流,计算出各支路实际的故障零序电流幅值和相位,还原了故障支路和非故障支路的有功分量差异,从而提高了选线的准确性.利用PSCAD进行相应的仿真计算,结果表明,基于该方法选择性接地保护故障支路与非故障支路动作差值较大,准确性高、抗干扰能力强,而且不易受故障相接地相位及接地方式和接地阻值的影响.
통과분석기우은태신호적유공선선원리,이급해방법영향선선준학솔적원인,제출료일충소제불평형전류적령서유공선선신방법.해방법통과산법소제전망불평형전류,계산출각지로실제적고장령서전류폭치화상위,환원료고장지로화비고장지로적유공분량차이,종이제고료선선적준학성.이용PSCAD진행상응적방진계산,결과표명,기우해방법선택성접지보호고장지로여비고장지로동작차치교대,준학성고、항간우능력강,이차불역수고장상접지상위급접지방식화접지조치적영향.
By making a thorough analysis of active line selection principle based on stable signal and the course of fac-tors affecting the accuracy of line selection, a novel zero-sequence active line selection method which can eliminate the influence of unbalanced current is proposed.In the method, the amplitude and phase of actual fault zero sequence current are calculated so as to eliminate the influence of unbalanced current in the grid and enlarge the differences of active component between the fault feeder and the sound feeder, thereby, improving the accuracy of line selection.The corresponding simulation is carried out by using PSCAD.Simulation results show that the selective protection principle based on the proposed method has a high accuracy and a great ability of anti-disturbance.The method is al-so applied to any distribution system with different grounding patterns and not be affected by the value of grounding resistance or the phase of fault line.