智能变电站中性点非有效接地系统接地保护研究

Research on Grounding Fault Protection of Neutral Non-effective Grounding System in Smart Substation

接地保护是电力系统继电保护的重要组成部分,传统的接地保护装置存在可用故障信息有限、响应速度慢、算法复杂、可靠性低等问题,严重影响供电质量和运行效率的提高。智能变电站为解决单相接地保护提供了新的思路,以多智能变电站为基础,构筑区域集控式智能供电体系,通过GOOSE网络实现信息共享,构造故障识别与隔离系统,对站内信息集中处理、综合判断,采用基于分布式终端之间对等交换数据的智能控制技术,提出零序全电流功率方向原理,重点研究基于多判据的单相接地保护判据的构造以及GOOSE网络传输关键技术,保证了单相接地保护的选择性与可靠性,有效解决了传统保护方式存在的各种问题,为智能变电站多判据继电保护的实现提供了理论分析基础。

Grounding fault protection is an important part of power system protections. Conventional grounding fault protection device has many problems, such as limited available information, slow response, complex algorithm and low reliability, which seriously affect the quality of power supply and operational efficiency. However, smart substation offers a new way to solve the problem of single-phase grounding protection. Based on multi-intelligent substations, a regional centralized control smart power supply system was built, the information was shared through GOOSE network, and a fault identification and isolation system was also established, which can make the information concentratedly processed and comprehensively judged. Based on the intelligent control technology for peer to peer data exchange among distributed terminals, the principle of zero sequence full cun＇ent power direction was put forward, the criterion of single-phase grounding protection based on multi-criterion and the key technologies of GOOSE network transmission was addressed, which can ensure the selectivity and reliability of single-phase grounding protection, and effectively solve the traditional problems and provide a theoretical foundation for multi-criteria relay protection of smart Substation.