交流系统故障导致直流线路保护动作的分析

利用直流保护的数字式波形回放系统,分析了2008年6月18日广东电网罗洞变电站发生500kV电流互感器爆炸事故期间高坡站的直流线路行波保护和直流线路电压突变量的保护动作行为。按照直流保护动作原理和逻辑,直流保护的动作行为符合设计逻辑,但违背了交流系统故障期间直流保护应可靠地不动作的设计规范,并就直流线路电压突变量保护提出了改进方案。所提出的增加保护动作延时的措施已用于天广、高肇、兴安直流工程。     

应用数字式波形回放系统分析“5·5”兴安直流输电线路闭锁故障

介绍了2008年5月5日兴安直流输电线路双极闭锁故障的详细过程,应用数字式波形回放系统分析了故障过程中直流保护的动作行为,认为兴安直流输电线路与接地极线路同时遭受雷击是造成直流双极闭锁的原因,现场巡线结果验证了该结论的正确性。根据分析结果,提出并采取了同时调整接地极线路电流不平衡保护在直流单极大地运行模式和双极运行模式下的逻辑参数的措施。     

应用数字式波形回放系统分析“5·5”兴安直流输电线路闭锁故障

介绍了2008年5月5日兴安直流输电线路双极闭锁故障的详细过程,应用数字式波形回放系统分析了故障过程中直流保护的动作行为,认为兴安直流输电线路与接地极线路同时遭受雷击是造成直流双极闭锁的原因,现场巡线结果验证了该结论的正确性。根据分析结果,提出并采取了同时调整接地极线路电流不平衡保护在直流单极大地运行模式和双极运行模式下的逻辑参数的措施。     

利用波形回放分析线路保护动作行为的方法研究

对500kV百色站1号主变压器跳闸事故中220kV百沙I、II回线路保护动作进行分析,描述了利用波形回放对200kV线路保护跳闸行为进行分析的实现方法。指出波形回放是验证保护装置动作行为的重要方法。     

AD采样异常引起电流差动保护动作分析

结合保护装置的动作情况及录波波形,分析电流差动保护动作行为并论证其动作逻辑,分析认为是变电站侧某线路第一套微机电流差动保护装置采样异常引起差流导致保护动作。     

基于G格式的保护逻辑可视化展示系统方案设计

针对目前电力系统故障分析和继电保护动作行为评价中存在的效率低等问题,提出一种基于G格式的保护逻辑可视化展示系统实现方案。首先,介绍了电力系统图形描述规范表达图形的方法,提出了基于G格式的保护逻辑可视化展示系统总体设计方案;其次,通过分析基于G格式的保护装置总体设计方案,研究了保护装置中实现基于G格式的保护逻辑图抽象的方法,以及在综合应用服务器中实现可视化展示和回放的步骤;最后,对所提方案可视化展示与回放效果进行了示例展示。展示结果表明该系统能够以时间为线索,清晰再现保护装置故障过程中各保护功能元件的动作逻辑和顺序,提高发现保护装置隐形故障的效率。     

交流滤波器保护装置误动分析及其改进

针对云广直流输电工程试验过程中出现的交流滤波器保护误动作事件,分析保护装置和故障录波器的故障录波,指出采样过程中的频率混叠是导致保护误动的原因,且由于不同保护装置采样的相对时差导致采样结果中频率混叠程度有差异,从而造成了双套保护动作行为的不一致。对保护装置提出了两项改进措施,进行了效果验证,并做了多种工况下RTDS仿真试验和现场故障波形回放试验。试验结果表明,保护装置经改进后可以有效地避免功率调整过程造成的保护误动。     

云广直流系统交流滤波器保护误动作分析及改进措施

针对云广直流输电工程中多次出现的交流滤波器保护跳闸事故,根据保护装置硬件原理分析说明了保护动作行为不一致的根本原因。在对故障录波进行分析的基础上,指出在延时整定方面,延时时间与保护装置动作时间存在差异,提出了相应的改进措施,并利用RTDS数字仿真系统进行仿真试验和现场故障录波回放试验。试验结果表明,改进后的保护可以有效避免冲击电流造成的保护误动。     

云广直流系统交流滤波器保护误动作分析及改进措施

针对云广直流输电工程中多次出现的交流滤波器保护跳闸事故,根据保护装置硬件原理分析说明了保护动作行为不一致的根本原因.在对故障录波进行分析的基础上,指出在延时整定方面,延时时间与保护装置动作时间存在差异,提出了相应的改进措施,并利用RTDS数字仿真系统进行仿真试验和现场故障录波回放试验.试验结果表明,改进后的保护可以有效避免冲击电流造成的保护误动.     

徐行站P546光纤纵差线路保护逻辑分析

P546保护是ALSTOM公司生产的数字式光纤电流差动保护,用于500kV徐行站和顾路站。介绍了该保护装置的三大功能及保护逻辑,重点分析了电流互感器(TA)断线、差动、远跳、跳闸出口等功能的逻辑动作行为。     

新一代微机继电保护测试仪及其基本性能

为微机型继电保护装置和安全自动装置测试的需要，以M2000为例，详细介绍了基于DSP、大功率开关放大器和PC机研制而成的新一代微机型继电保护测试仪，介绍了它的基本性能，描述了该仿真器软、硬件的实现，以及仿真器的功能，如电力系统实时仿真、谐波发生器、故障波形成回放、系统振荡模拟、各种类型的继电器测试。该测试仪体积小、重量轻、操作方便，可广泛适用于继电保护生产厂家、实验室、电厂、变电站等场所测试各类继电保护装置。     

The new science of protective relaying in the petrochemicalindustry

The multifunction digital relay has greatly expanded the science of protective relaying. The new science of protective relaying has resulted in the following improvements and benefits to the petrochemical industry. The multifunction relays typically have a large array of functions that can be used for electrical equipment protection. The multifunction relays are typically less costly than the equivalent package of discrete electromechanical and solid state relays. The programming logic provided by most multifunction relays allows for sophisticated protection schemes that were either not possible or economical with the discrete protection components of the past. The burden requirements of the multifunction relays are typically very low. With increases in technology, the testing and calibration of protective relays is changing. Advances in technology in the future may result in a decreased life expectancy of protective relay packages of the future     

基于IEC61850数字化变电站实施的若干探讨

讨论了基于IEC61850的数字化变电站工程实践中存在的ICD文件的描述、IEC61850数据模型、继电保护定值与保护事件的上送和继电保护的配置问题和解决方案.     

Algorithmic-knowledge-based adaptive coordination in transmission protection

Changes in power system operating conditions can affect both the reach point of distance relays and the coordination of distance and overcurrent relays. To improve the performance of the protection system, an adaptive scheme of relay settings is proposed. That is possible since the protection relays became digital . This paper describes a system for online adaptive setting and coordination of protection relays in meshed networks where the backup protection is achieved in remote form. After changes in the state of the network, an expert system (ES) performs the detection and proposes the correction of erroneous settings of protection zones and miscoordinations between relays at different stations; through an algorithm based on a fast determination of a nonminimal set of "break-points" (BPs) relays , new time characteristics for the coordination are found. The results of the application of the developed system to a test network of 34 nodes, 55 branches, and 110 relays are shown.     

低压配电系统微机逻辑闭锁保护的原理与设计

提出了一种用于35（66）kV及以下电压等级配电系统的微机逻辑闭锁保护新方案,包括配电线路保护和配电变压器保护。分析了所采用的逻辑闭锁保护新原理,介绍了硬件构成、动模试验及试运行结果。这种保护可认为是在点保护基础上的面保护,可有效解决低压配电系统上下级保护定值不易配合、动作选择性差的问题。     

Protection of power transformer using multi criteria decision-making

Power transformers are protected by different relays that operate independently. Malfunction of each relay has a major role in reducing the reliability of the protection system. In order to mitigate the main drawbacks of the power transformer relays, an overall protection scheme is presented in this paper. This scheme proposes a novel multi criterion algorithm using decision-making based on fuzzy logic. In this paper the outputs of restricted earth fault relay and a directional check unit, are combined with the output of the differential protection relay. Therefore, problems that are pertaining to independent operation of each relay have been mitigated and the relays cover protection blind spots of each other. The improved power transformer protection (IPTP) scheme enhances the sensitivity and reliability of the power transformer protection. Extensive simulations are used to measure the effectiveness and merit of the proposed IPTP relay. The above efforts result in a multi criteria approach for protection of power transformers.     

5G通信自同步配网差动保护研究与应用

随着分布式电源的高度渗透和环网结构的逐步增多,配电网迫切需要电流差动保护应对过流保护面临的挑战。基于5G的商用化契机,研究开发一种基于5G通信的配电网分布式差动保护。该保护采用基于移动边缘计算的切片网络作为数据通道,具有超低延时和超高可靠的特点;采用基于故障时刻的自同步方法解决差动保护两端的数据同步问题,无需增加额外对时装置。在5G智能电网应用示范区,对所开发装置进行了单基站和跨基站环境下的综合测试,并投入10 kV线路试点运行。现场测试结果与试运行数据表明,差动保护性能满足配电网工程应用要求。     

Ground Distance Relaying With Fault-Resistance Compensation for Unbalanced Systems

Fault resistance is a critical variable in distance relaying. If not considered due to underreaching phenomenon, it may cause the misoperation of ground distance relays for internal faults. Still, as a consequence of the overreaching phenomenon, the unbalanced nature of loads and asymmetry of lines can affect the distance protection operation efficiency. Mainly due to these aspects, there is low precision in protection zone limits of ground distance relays. In this paper, a new algorithm is proposed to increase the precision of these limits, improving efficiency in the distance protection process. The proposed method is based in phase coordinates and uses a fault resistance estimate to develop the trip decision procedure. The results show that the algorithm is suitable for online applications, and that it has an independent performance from the fault resistance magnitude, the fault location, and the line asymmetry.     

Sensitivity improvement of time overcurrent relays

In this paper, we recommend a new adaptive function for time overcurrent relays. The purpose of the adaptation process is to improve the sensitivity of time overcurrent relays, which then operate with a dynamic pickup setting such as a load current. The results obtained from time overcurrent adaptive relays are collated, and the results from analysis of negative sequence relays and conventional time overcurrent relays are also presented. In this article, we describe the control logic structure of an adaptive pickup current and its performance under different operating states.     

C.A.E. Software for Transmission Protection System: Puget Power Experience

One major concern of a protection engineer is to achieve successful coordination of all relays in a transmission network. This tedious and laborious process is usually accomplished manually at present. In this paper we present the results of a Computer-Aided Protection System based on our experimentation with the entire 115 kV transmission network of Puget Sound Power and Light Company (Puget Power), which consists of 38 buses and 61 lines. The protection package entails algorithms for both overcurrent and distance relays. Effective man-machine interaction is provided by means of computer-graphics. Such interaction is invaluable in providing the protection engineer with both the details of coordination process and the control over this process. A novel feature of the package is the performance and analysis feature for overcurrent relays. The results for the above system are provided and the execution times for different test cases using an IBM 4341 computer system are also presented.