【中文摘要】基于光纤的数字式分相电流差动保护,已成为输电线路理想的主保护。但在实际运行中尚存在一些问题,如CT饱和、负荷电流、分布电容电流及双端数据同步等问题,都可能使保护误动或闭锁。文章针对目前光纤电流差动保护在实际运行中所面临的几个问题进行了分析,特别对分布电容电流和双端数据同步展开了研究。对国内外几种典型动作判据进行了总结。针对CT饱和的问题,深究了产生它的原因,并指出光电式电流互感器可以解除这一瓶颈。对重负荷下负荷电流对差动保护的影响,基于故障分量的差动保护可以有效的避免其影响,但故障分量存在时间短且较难提取。针对超高压长线路分布电容电流的影响,特别是对T接线路有无并联电抗器补偿进行了分析计算并进行了仿真,得出时域暂态补偿优于稳态补偿,但在空载合闸等情况下仍无法完全补偿。针对双端数据同步,引入装置“时钟差”的概念,以传统的“乒乓对时”为主,辅助以电气量对时,可以解决由于双端保护收、发数据延时不同,引起差动保护产生不平衡差流甚至保护误动的问题。基于贝瑞隆线模法的分相电流差动保护,通过比较同侧电流量而非异侧电流量,从模型上克服了分布电容电流的影响;采样值差动保护具有动作速度快、计算量小的优点,且具有“天然的”抗CT饱和的能力;而基于贝瑞隆模型的采样值差动保护兼具了两者的优点,文章分单相与三相进行了详细的推导计算,对一些典型故障作了仿真验证,证明了此判据的有效性与优越性。最后,对全文内容进行了总结,并对下一步的工作进行了展望。
【英文摘要】Fiber-based digital current differential protection, has become the ideal main protection of transmission line. However, there are still some problems in actual operation, such as CT saturation, the load current, the distributed capacitance current and double-end data synchronization problems, be likely to make protection maloperation or closure.This paper analyzes several problems which exist in actual operation of optical fiber current differential protection, especially researches distributed capacitance current and double-sides data synchronization.It summarize several typical criterion of the domestic and abroad. It researches its reasons about the problem of CT saturated, and points OECT can solve this problem. Fault- based component current differential protection may avoid the effect of load current, but exist time of fault component is very short and more difficult to extract. For the effect of EHV long lines for the distributed capacitance, especially to T circuit, is analyzed and simulinked whether the shunt reactor, concluded that domain transient is better than the steady-state compensation, but it could not still compensate fully in the case of no-load closing and other.For the double-end data synchronization, the introduction of device “Clock poor” concept, based on the traditional “ping-pong time”, aiding to electric, it can solve the problem that no synchronization of double-sides data, protection misoperations because of imbalance current. Bergeron long line modeling method-based phase current differential protection, it overcomes the impact of distributed capacitive current by comparing the current of same rather than the opposite side; Sampling value differential protection has the advantages of the movement speed and low computation, what is more, which itself has a “natural “ anti-CT saturation capacity; Sampling value differential protection based on Bergeron model owes both of their advantages, it analyzes single phase and three phase fault, and then makes a number of typical fault simulation, demonstrates its effectiveness and superiority.Finally, It summaries the full text, and prospects the further work.
【关键词】输电线路 光纤 电流差动保护 分布电容 双端数据同步 贝瑞隆模型 采样值差动
【英文关键词】fiber phase current differential protection distributed capacitance double-sides data synchronization Bergeron model sampling value differential protection
【目录】超高压输电线路光纤分相电流差动保护的研究摘要6-7Abstract7第1章 绪论10-151.1 课题研究的背景和意义10-111.2 输电线路电流差动保护的发展历史与现状11-131.3 我国光纤通信网的现状13-141.4 论文的主要工作141.5 本章小结14-15第2章 光纤电流纵联差动保护原理15-272.1 引言152.2 光纤保护的基本原理15-162.3 电流向量差动保护的实现16-202.3.1 基本原理16-172.3.2 不平衡电流的影响及对策17-202.4 差动保护动作判据的分析20-222.5 故障分量电流差动保护22-252.5.1 双端电源线路区内外故障22-242.5.2 相电流突变量分相差动保护24-252.6 零序电流差动保护25-262.7 本章小结26-27第3章 电流差动保护电容电流补偿方法的研究27-393.1 引言273.2 电容电流对电流差动保护的影响273.3 电容电流补偿方法27-353.3.1 基于稳态的电容电流补偿的研究27-333.3.2 基于暂态的电容电流补偿的研究33-353.4 仿真分析35-383.5 本章小结38-39第4章 光纤电流差动保护的通信39-494.1 引言394.2 差动保护的通信方式39-424.2.1 光纤差动保护的数据传输39-404.2.2 光纤差动保护的时钟设置40-424.3 数据的采样同步方式42-4.3.1 基于数据通道的同步方法42-444.3.2 基于参考向量的同步方法44-454.3.3 基于时钟基准源的同步方法45-4.4 建议采用的数据同步方案46-484.5 本章小结48-49第5章 基于贝瑞隆模型的分相电流差动保护判据49-655.1 引言495.2 贝瑞隆分相电流差动保护49-565.2.1 输电线路贝瑞隆模型49-535.2.2 保护动作判据53-545.2.3 动作判据的计算方法54-565.3 仿真验证56-635.4 本章小结63-65结论65-67致谢67-68参考文献68-72下载本文