CAJ | 학술논문

超高压线路保护在运行中受负荷波动影响，负荷不对称的线路在正常运行时，都存在较大零序电流，为防止频繁启动不得不提高启动值，从而降低了启动元件的灵敏度，导致现有的零序电流判据对经高阻接地的故障无法灵敏判别，不能满足超高压线路保护对启动元件快速性的要求。提出一种采用线电压、同相间电流同步变化量开放的相间启动判据和零序电流、相电流同步变化量比较方式的零序启动判据。通过PSCAD/EMTDC仿真表明，如果使用同步变化量的启动判据，保护的灵敏度、快速性和可靠性均有一定程度的提高。
초고압선로보호재운행중수부하파동영향，부하불대칭적선로재정상운행시，도존재교대령서전류，위방지빈번계동불득불제고계동치，종이강저료계동원건적령민도，도치현유적령서전류판거대경고조접지적고장무법령민판별，불능만족초고압선로보호대계동원건쾌속성적요구。제출일충채용선전압、동상간전류동보변화량개방적상간계동판거화령서전류、상전류동보변화량비교방식적령서계동판거。통과PSCAD/EMTDC방진표명，여과사용동보변화량적계동판거，보호적령민도、쾌속성화가고성균유일정정도적제고。
UHV line protection devices are easily affected by load fluctuation. Lines with asymmetric load car-ry larger zero-sequence current in normal operation. So the starting value has to be increased to prevent fre-quent starts. Therefore, sensitivity of starting components is reduced and faults due to high resistance ground-ing cannot be sensitively determined by existing criterion of zero-sequence current, which fails to meet the requirement of UHV lines on rapidity of starting component. This paper puts forward a new starting algorithm, in which interphase startup criterion is based on phase-to-phase synchronous current variation value with syn-chronous current variation value abrupt change, zero sequence startup criterion is based on the mutations cur-rent synchronous variation value of zero sequence compare with the abrupt change of phase current value. It is proved by PSCAD/EMTDC simulation that starting criterion based on synchronous variation can improve sen-sitivity, rapidity and reliability of UHV line protection devices.