Three-dimensional magnetic field analysis of electrodes for VCBs[vacuum circuit breakers]

This paper describes the application of three-dimensional magnetic field analysis, including eddy current effects on the axial magnetic field electrodes of vacuum circuit breakers. The accuracy of the analysis is verified with both basic and full models of the electrodes. The analytical results were compared with measured values obtained by a Hall sensor system. The effect of the electrode slit length and the electrical conductivity of the contact on the magnetic flux density and phase difference was analyzed with the full model. The magnetic field in the gap was simulated when the arc ignites between the electrodes. These results demonstrated that the magnetic design of the electrodes can be carried out on an engineering workstation     

SF6断路器分布式在线监测系统的研制

本文研制了一种分层分布式SF6断路器在线监测系统,该监测系统主要由监控中心主机、现场数据采集单元和网络通信处理单元组成。系统上层网络采用以太网的通信方式,下层网络采用CAN总线的通信方式。对SF6断路器故障诊断所需的在线监测系统进行了分析,详细阐述了在线监测系统各部分的硬件结构及软件实现。经现场运行表明,该系统布线少、配置灵活、传输数据可靠,并具有可扩展性。     

History of vacuum circuit breakers and recent developments in Japan

Vacuum circuit breakers (VCBs) have been developed and widely applied in Japan to meet the requirements of increasing energy consumption and also in national security of various areas. As a result, for example, a 168 kV two break porcelain type and a 100 kA one break VCB have already appeared in the Japanese market and they are currently being exported to world-wide markets. VCBs interrupt currents in vacuum, and this means they do not exhaust dissolved gases which are sometimes harmful to the human body or cause effects on the environment. Therefore, by its nature, the recycling of materials and safety to the human body have been realized, and also no global warming effects would be expected. Energy is extremely essential and important in human daily life, and many types of circuit breakers play important roles in electrical power transmission and distribution systems to maintain the systems reliability and safety by switching the systems under several conditions. Since vacuum circuit breakers possess a lot of advantages such as high current interrupting capabilities, small size, and low cost, they will be used much more in the future, and at this moment, we believe it is very worthy to discuss and consider thoroughly future trends of VCBs. In this paper, the results of the developments in Japan will be reviewed, the reflection of the results will be stated, and the subjects of engineering in the 21st century will be discussed. These will include recycling, safeguards to the human body and the fireless nature of VCBs; and it will be demonstrated that the developmental works of VCBs are being wonderfully explored in Japan now and in the future.     

Surge limiters for vacuum circuit breakers

Computer modeling was used to confirm the applications which require surge protection and to verify that surge limiters installed within the switchgear will provide this protection. The basic phenomena which cause vacuum-switchgear-related surges are reviewed, and the need for surge limiters is discussed. Also described is the design of these surge limiters. Information and performance data for their applications are provided. The potential sources of switching overvoltages are reviewed and the basic requirements of surge limiters are described     

真空断路器的永磁操动机构

永磁操动机构是新一代真空断路器的操作系统，是由机械操动向电子操动转变的关键。首先，通过分析典型永磁操动系统等效电路，在一定的冗余下优化励磁电流波形，使所需的脉冲功率最小；然后对永磁操动机构的使用可靠性问题，即能源部分的失效问题、控制部分的电磁兼容问题和磁系统的磁性能劣化问题进行了讨论。     

真空断路器的调整与维护

1.真空断路器的调整真空断路器目前在输配电系统中的投入越来越多,在使用前,4个方面必须要调整和检查。 (1)行程开距的调整:真空断路器的操动机构总行程和真空灭弧室的触头开距随开关的电压等级不同而有所差别,达不到要求的应该进行调整。有2个办法,首先,调节缓冲垫的厚度;其次,调整动导电杆端的可调螺钉。 (2)超行程的调整:一般情况下的超行程是触头开距的15％～40％。调整的方法是动导电杆端可调整螺钉与绝缘拉杆的可调螺钉互相配合调整。     

SF6断路器综合在线监测系统的开发

SF6高压断路器综合在线监测系统可以同时对多组断路器运行时的相关参数进行全面测量,为故障的综合诊断提供依据.在对SF6断路器运行状态进行实时监测的同时,通过建立数据库,实现对断路器在线监测数据的历史和横向的管理,有利于断路器在线监测信息共享,具有用户界面友好,易于维护等特点.     

Strategies for selecting monitoring of circuit breakers

Diagnostics and monitoring can be used to optimize maintenance practices, replacement, and utilization of aged circuit breakers. Monitoring practices should be selected with realistic expectations. Monitoring techniques and strategies for circuit breakers can vary depending on the application. Some monitoring techniques do not provide sufficient benefit to justify the cost and effort. Conversely, appropriate selection of monitoring can provide significant benefits. A new "IEEE Guide for the Selection of Monitoring for Circuit Breakers" has been published. It outlines the majority of monitoring options, and includes the important role and application of failure modes and effect analyzes. Various monitoring techniques and strategies are reviewed using the new guide as a reference for selecting the most appropriate monitoring for a given application.     

基于自适应预测的同步断路器

介绍一种基于弹簧操作机构的真空同步断路器.该同步断路器以TI2812DSP为控制核心.可实现在电网电压预定相位处合闸的功能,从而可大大缩短合闸操作暂态过程,提高电网电能质量.分析实现断路器同步控制的原理和影响弹簧机构动作时间的因素,并据此提出基于时间序列的自适应预测控制策略.可显著提高断路器同步动作的准确性和可靠性.随后采用高性能数字信号处理器(DSP)实现断路器同步控制器样机,并对上述控制算法进行试验验证.试验结果表明:同步断路器可以实现在电网电压预定相位精确合闸:当环境变化、控制电压波动及弹簧老化等原因引起断路器动作时间偏离时,自适应控制器能够在三四个动作周期内迅速修正偏差.重新回到并保持同步状态.     

Life mangement of SF6 circuit breakers based on monitoring and diagnosis - [Feature Article]

In order to provide an accurate estimate of a circuit breaker's remaining lifetime, reliable measurements of ageing and failure characteristics and condition monitoring, are necessary. In order to obtain this documentation, it is necessary to monitor the performance parameters which are most sensitive to aging. Following comprehensive data acquisition and data analysis, it should be possible to develop a comprehensive electro-thermo- mechanical life model which accurately describes the aging behaviour of circuit breakers.     

LW11-252型SF_6高压断路器在线监测系统的开发

指出目前断路器在线监测和诊断技术存在的问题.在对SF6断路器状态参数进行实时监测的同时,总结出适用于LW11-252型SF6高压断路器在线监测的方法,介绍了该监测系统的开发原理及系统构成.以合、分闸线圈电流、触头行程-时间持性曲线及触头寿命为系统监测参数,介绍了断路器故障的分析与预测方法.     

40．5kV真空断路器运行分析

近年来,40.5 kv断路器的故障率较高,如2005年国家电网公司系统40.5 kv断路器发生故障146台·次.故障率为0.304(台·次)/(100台·a),是所有电压等级断路器故障率上升最高、最快的,比2004年上升176.3%.其中早期常用型断路器,如户外ZW7、户内ZN12,故障率最高,故障类型又以绝缘故障为主.虽然近年来电力系统设备量增长较快,使故障率有所增长,但设备本身的质量问题也较多,不容忽视.仅就40.5kv电压等级的真空断路器运行中存在的问题进行分析,以便引起同行的关注.     

新一代中压真空断路器(VCB)

一、前言 真空断路器在中压(6～36kV)电网是占优势的电器,以欧洲和美国为例,VCB在全部产出的各种断路器中占70%,日本近100%.俄罗斯的VCB产量呈稳定增长,1997年VCB的份额占全部的50%以上.VCB和油断路器及充气断路器(GCB)相比,其作用在市场上被看好的主要优点有:     

Simulation of reignition processes of vacuum circuit breakers inseries

The present theoretical study is based on experimental investigations and shows the transient behavior of vacuum tubes in series, in the case of reignition. Neglecting the real physical arc and replacing it by a programmable switch (time controlled), it can be demonstrated, in a preliminary study, that the theoretical studies do confirm the experimental results     

Breakdown voltage of electrode arrangements in vacuum circuit breakers

The prediction of HV strength of electrode arrangements in vacuum is complex. A comparison of experimental results from different labs is quite difficult, because they are influenced by a wide range of parameters like electrode material, surface finish, surface area, conditioning state of the surface and the geometry of the electrode arrangement. The aim of this work is to find an empirical relation between the breakdown voltage and different electrodes parameters. Shielding arrangements and main contacts of vacuum tubes are of particular interest. For this purpose, models of contacts and shield electrodes made of stainless steel are stressed with lightning impulse voltage. Several methods of surface finishing are applied to obtain reproducible conditions. The experimental results and deliberations for an empirical approach are presented. In addition the results are related to numerical field calculations.     

基于IEC61850标准的断路器在线监测装置

介绍了断路器在线监测技术发展状况,对断路器监测的关键特征指标和功能配置进行了分析.介绍了一种基于IEC61850通信标准的中、高压断路器在线监测装置,通过其在华东500 kV徐行变电站状态检修系统中的应用,对数字化变电站的在线监测扩展子系统进行了有益的探索.     

Continuous monitoring of circuit breakers using vibration analysis

This paper reports the results from three years of continuous condition monitoring of high-voltage circuit breakers (CBs) using vibration analysis. More than 1000 vibration patterns from the operating mechanism of three different spring-operated SF/sub 6/ breakers in normal service are analyzed. The patterns are recorded during each opening/closing operation and compared with references to identify timing and frequency deviations. Two of the three investigated CBs were operating well, while the third suffered from several severe problems. A developing failure that caused this breaker to not open on command was identified in advance. The reproducibility of the vibration patterns is high for a faultless CB and this makes it possible to separate faulty conditions from natural variations. The vibration analysis method is, however, dependent on a well-conditioned vibration pattern without noise and with distinct events. If the instrumentation is made sufficiently robust to withstand both the electrical disturbances in a substation environment and the mechanical shocks during CB operation, vibration analysis seems to be a promising technique that can be used on a continuous basis to detect malfunctions in the operating mechanism.     

An approach for intelligent detection and fault diagnosis of vacuum circuit breakers

In this paper, an approach for intelligent detection and fault diagnosis of vacuum circuit breakers is introduced, by which, the condition of a vacuum circuit breaker can be monitored on-line, and the detectable faults can be identified, located, displayed and saved for the use of analyzing their change tendencies. The main detecting principles and diagnostics are described. Both the hardware structure and software design are also presented.     

An improved Mayr-type arc model based on current-zero measurements[circuit breakers]

In this paper, it is shown that the Mayr-type arc models can be used to describe circuit breaker arc behavior before current zero exactly. Based on this analysis, the different types of `modified' Mayr arc models can be explained. As a result of the theory, an improved Mayr-type arc model-with a constant time parameter and a cooling power which is dependent on the electrical power input-is introduced and used to reproduce current zero measurements successfully