CAJ | 학술논문

提出一种利用区内外初始行波信号的频率差异来区分内外部故障的快速保护原理。首先，详细分析母线杂散电容和阻波器对故障行波的影响；然后，对初始电流行波进行希尔伯特变换(HHT 变换)得到各频段的时频图，提取初始电流行波突变点频率，利用行波波头瞬时频率差异作为判据区分内外部故障。理论分析和仿真结果表明，该方法动作快，不易受故障类型、故障角度和故障接地电阻的影响，不存在保护死区，是一种简单有效的高压线路保护方法。
제출일충이용구내외초시행파신호적빈솔차이래구분내외부고장적쾌속보호원리。수선，상세분석모선잡산전용화조파기대고장행파적영향；연후，대초시전류행파진행희이백특변환(HHT 변환)득도각빈단적시빈도，제취초시전류행파돌변점빈솔，이용행파파두순시빈솔차이작위판거구분내외부고장。이론분석화방진결과표명，해방법동작쾌，불역수고장류형、고장각도화고장접지전조적영향，불존재보호사구，시일충간단유효적고압선로보호방법。
A rapid protection principle with the frequency difference of initial traveling-wave distin-guishing internal and external fault was proposed in this paper.Firstly,the influence of wave trapper and bus capacitance on the initial traveling-wave was analyzed.And then the time-fre-quency graph of initial current travelling waves was obtained by Hilbert-Huang Transform.The relationship of the catastrophe point frequency and wave trapper frequency was used to distin-guish external and internal fault.Theoretical analysis and simulation results showed that the method has advantages of high speed and little influence by the fault types,fault point and grounding resistance,and it is simple and useful for extra-high-voltage transmission line protec-tion without protection dead zone.