灵宝背靠背直流输电工程直流极保护系统三取二逻辑功能的实现

Realization of selecting 2 from 3 logic in DC pole protection system for Lingbao back-toback HVDC transmission project

直流输电系统保护除了与交流继电保护一样,能满足快速性、灵敏性、选择性和可靠性的要求,还必须具有足够高的RAM(Reliab ility、App lic ition、m aintainab ility)指标和冗余化设计。灵宝背靠背直流输电工程许继控制保护系统中直流极保护系统采取了与国内交流继电保护不同的三取二逻辑概念,对其原理及实现方法进行了阐述,同时也介绍在西门子不提供技术支持的情况下,实现运行状态与试验状态的自动转换功能,并在试验状态下能自动闭锁出口。灵宝背靠背直流输电工程目前已正式投入商业运行,直流极保护系统经历了工程实际的考验,验证了三取二逻辑及实现方法的合理性、正确性、有效性。

HVDC system must fulfil these requirements of speediness, selectivity, and reliability as AC protection system, Lingbao back - to - back HVDC project DC protection system adopts logic concept about selecting 2 from 3 , it is different from AC protection system in China. The logic about selecting 2 from 3 and the implement way are introduced. Without the techniques support from Siemens, this paper realizes the auto converse function of run state and test state, which can block signal output in the state of test automatically. Lingbao back -to -back HVDC project has now been test run, so the DC pole protection system has been tested and proved usefully in practice. The result indicates that the logic about selecting 2 from 3 and the implement way are designed successfully.