CAJ | 학술논문

传统行波极性比较式纵联保护可靠性受小故障初始角等因素影响较大。为提高行波纵联保护的可靠性，在分析线路两端电压和电流极性关系的基础上，提出一种新的极性比较式纵联保护算法。该保护算法利用故障后一段时间内故障电压和故障电流的 S 变换能量相对熵表征极性关系，进而根据线路两端S变换能量相对熵的比值来识别区内外故障。区内故障时，线路两端电压和电流的能量相对熵相差不大，其比值较小；区外故障时，线路两侧电压和电流能量相对熵差异明显，比值较大。基于PSCAD/EMTDC的仿真结果表明，该保护方案能够快速可靠地确定区内外故障，其性能不受故障初始角、过渡电阻、故障位置、故障类型和母线接线方式的影响。
전통행파겁성비교식종련보호가고성수소고장초시각등인소영향교대。위제고행파종련보호적가고성，재분석선로량단전압화전류겁성관계적기출상，제출일충신적겁성비교식종련보호산법。해보호산법이용고장후일단시간내고장전압화고장전류적 S 변환능량상대적표정겁성관계，진이근거선로량단S변환능량상대적적비치래식별구내외고장。구내고장시，선로량단전압화전류적능량상대적상차불대，기비치교소；구외고장시，선로량측전압화전류능량상대적차이명현，비치교대。기우PSCAD/EMTDC적방진결과표명，해보호방안능구쾌속가고지학정구내외고장，기성능불수고장초시각、과도전조、고장위치、고장류형화모선접선방식적영향。
The reliability of the traditional polarity comparison based pilot protection on is greatly influenced by such factors as small fault initial angle and so on. To improve the reliability of traveling wave pilot protection, on the basis of analyzing polarity relationships between voltages and currents at both ends of the transmission line, a new polarity comparison pilot protection algorithm is proposed. In the proposed protection algorithm the polarity relationship is characterized by the S-transform energy relative entropy of fault voltage and fault current within a period of time after the occurrence of the fault, and then according to the ratio of S-transform energy relative entropies at both ends of the transmission line the fault inside the protection zone is distinguished from the fault outside the protection zone. For the fault inside the protection zone the differences of energy relative entropies of voltages and currents at both ends are small; for the fault outside the protection zone the differences of energy relative entropies of voltages and currents at both ends are relatively large because the energy relative entropies at both terminals are quite different. Results of PSCAD/EMTDC based simulation show that the fault inside the protection zone can be rapidly distinguished from the fault outside the protection zone by the proposed protection scheme, and its performance is not affected by fault inception angle, transition resistance, fault position, fault types and busbar connection modes.