Evaluation of standard impulse voltage/current measuring systems in Japan

A national‐standard‐class impulse voltage measuring system in Japan was developed in the consignment research of the Ministry of Economy, Trade and Industry (METI) and New Energy and Industrial Technology Development Organization (NEDO) from 1998 to 2006. The standard measuring system for the impulse voltage measurements is managed by the Japan High Voltage Impulse Testing Laboratories Liaison (JHILL) established under the Japan Electric Machine Industry Association (JEMA). The standard impulse voltage measuring system calibrates other measuring systems and assesses their uncertainties, and, therefore, its uncertainty needs to be evaluated independently. The principal components of the system are a voltage divider, a digital recorder, and a low‐voltage calibrator which generates impulse voltages of known peak voltages and waveforms. Moreover, a reference measuring system for impulse current in Japan was also developed in 2009 supported by JEMA. Its international compatibility was confirmed through an international comparison test. Through domestic comparison tests, traceability among transducers of impulse current in Japan was established. In this paper, the constitution of these measuring systems, their performance, and related latest activities, such as comparison tests, are described. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

利用CVT冲击电流监测过电压技术研究

介绍目前电力系统过电压监测技术存在的不足基础上,利用变电站母线CVT回路电流测量实现母线过电压监测的原理与系统构成,为过电压监测提供了一种经济适用的方法。     

International comparison of HV impulse measuring systems

The authors studied the agreement between laboratory measurements of full and front-chopped lightning impulses at four national laboratories. First, some general information on how standards are maintained and disseminated is presented together with a brief review of the requirements for HV impulse measurements. Then, the comparative measurements made in the four national laboratories are presented and the relative differences are reported. Comparative measurements can be made for full standard lightning impulses to within 1% for crest voltages and to within 5% for front times. These uncertainties may be adequate to allow the calibration of industrial measuring systems to within 3% for crest values and 10% for front times, as is required by the relevant standards, provided the systematic errors of the reference system are sufficiently small     

以电流为判据的厂用电源快切原理及实现

分析了发电厂厂用电源现有快切装置的现状和依据,提出了通过计算备用电源电压和母线残压之间的差拍电压有效值与断电后母线残压初始频差的乘积,以预测冲击电流的大小,并以此为判据的快切新原理。该方法综合了现有方案的长处,可避免单一参数(频率差、相角差或电压差)不满足就闭锁快切的弊端。以135MW和300MW机组为例,给出了切换时的实录数据,结果表明:该方法可最大限度地发挥快切的功能,提高快切成功率及切换质量。     

可再生能源国际标准的现状及发展

标准化对推广可再生能源技术的应用甚至主导其发展具有举足轻重的作用.文中简介了国际级、区域级、国家级及特定行业标准制定机构,阐述了可再生能源国际标准的进展情况,分析了中国参与国际可再生能源标准制定情况,提出了我国在可再生能源标准化工作上的建议.     

电磁脉冲测量技术分析

本文设计了一种时域天线,具有超宽带特性,在频带范围内天线端口反射系数小于-10dB（VSWR〈2）,可以确保电磁脉冲测量的不失真。并且在脉冲测量中用了一种对此时域天线的新的分析方法,即引入了转移函数。根据现有理论可以计算出测量系统所用的同轴传输线的损耗。最后利用宽带示波器显示的测量信号的结果,通过此显示的信号能很容易的计算出需要测量的脉冲信号。     

Comparisons between impulse voltage calibrators and digitizers

Impulse voltage calibrators are important instruments for the calibration of impulse voltage digitizers and other measurement devices. The impulse digitizers, on the other hand, are often sufficiently accurate for checking the performance of impulse voltage calibrators. Comparisons between impulse calibrators and digitizers are useful in determining the uncertainties of the instruments, especially when multiple devices are being cross compared. In this paper, comparisons among calibrators and digitizers from Nippon Institute of Technology (NIT), Japan, National Measurement Institute (NMI), Australia, and Korea Electrotechnology Research Institute (KERI), Korea, are reported. Comparisons of full lightning impulse and switching impulse waveforms were performed. The results of the comparisons are reported with an analysis of the sources of the uncertainties. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

中性点不接地配电网电容电流在线测量方法比较

配电网电容电流大小是决定是否装设消弧线圈、确定消弧线圈容量和进行消弧线圈调谐的重要依据.论文分析测试了国内提出的中性点不接地配电网电容电流在线测量方法(三频率注入法、两频率注入法、相量法和谐振法),首次分析了电压互感器漏电阻和漏电抗对测量精度的影响,给出了各测量方法的优缺点,比较了测量范围和测量精度,为现场电容电流测量方法的选择提供参考.     

基于LabVIEW的冲量测试系统开发

在火工品验收检测中,爆炸冲量是一个非常关键的参量。炸药在空中爆炸时生成的空气冲击波的峰值和冲量是炸药能量特性和性能的一项重要参数,也是衡量弹药爆破及杀伤效果的一项重要指标,其准确测量具有重要的意义。为了对火炸药是否合格有准确的评判,本文研制开发了冲量测试系统。选择高精度传感器并进行了信号调理电路设计,基于LabVIEW软件平台,扩展了传感器检测系统,使整个冲量测试自动化完成,实现了冲量的智能化测试。系统具有自动化程度高,操作简单方便,响应时间短和测量精度高等优点。     

Latest research activity on the standard of high‐voltage impulse in Japan

A national‐standard‐class impulse voltage measuring system in Japan was developed in the consignment research of the Ministry of Economy, Trade and Industry (METI) and New Energy and Industrial Technology Development Organization (NEDO) from 1998 to 2006. The standard measuring system for the impulse voltage measurements is to be managed by the Japan High‐voltage Impulse testing Laboratories Liaison (JHILL) established under the Japan Electric Machine Industry Association (JEMA). In this paper, the composition of this standard measuring system, its performances and international compatibility, the domestic traceability system and related latest activities are described. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Application of step‐response test for evaluation of uncertainty of standard measuring system for lightning‐impulse high voltage

In evaluating the uncertainty of the standard measuring system for lightning‐impulse high voltages, which is composed of a standard voltage divider, a digital recorder, and calibrators, step‐response tests of the standard voltage divider may be useful. In this paper, a convolution algorithm is employed to calculate the output impulse voltage waveforms from measured step‐response waveforms. The uncertainties of peak‐value measurement due to the influence of the nominal epoch, uncertainty of the peak‐value measurement due to dispersion of the AC scale factor, and uncertainty of the virtual front‐time measurement due to long‐term stability are evaluated. Furthermore, the error of the virtual front time of the output waveforms is discussed. The front part of the step‐response waveform, t≤ T₃₀%, does not influence the error of the virtual front time. Therefore, for the standard voltage divider, the step‐response parameters, that is, the experimental response time, partial response time, settling time, and overshoot, have almost nothing to do with the error of the virtual front time. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(2): 24–32, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21279     

电动汽车国际充电标准发展趋势

近年来,主要汽车大国纷纷开展电动汽车的研发与生产,但发展方向却不尽一致。因各国电力系统存在差异,故电动汽车在充电设备及规格、车辆设计等方面的研发方向就各不相同。对主要汽车大同日本和欧美的电动汽车充电标准进行比较研究,并对我国所应采取标准化行动提出政策建议。     

高频信号注入法测量配电网电容电流及滤波的研究

为解决信号注入法测量配电网电容电流方法的频率选取和工频干扰等问题,分析了高频信号注入法的原理并对高频法进行改进。首先通过注入5 000 Hz高频信号求得电感值,然后通过扫频确定电网谐振频率,根据公式可计算出配电网对地电容值,并在扫频时通过串联电容的方法降低大对地电容系统的电容值,实现大对地电容系统电容电流的测量。同时运用数字信号处理器TMS320F28335,采用有限冲击响应滤波器(FIR)算法实现滤波功能,滤除扫频时注入信号中的工频干扰。通过理论分析和实验验证,该方法能够增加测量对地电容的范围,简化计算,滤除工频信号,使测量时的相对误差均不超过5%。     

油浸式变压器现场振荡型冲击耐压试验方法

为满足油浸式电力变压器现场振荡型冲击耐压试验的需要,基于MARX回路,根据变压器的结构特点,提出了试验电压的产生方法和试验接线方法。仿真计算和模拟试验表明:在构成的双指数波形冲击电压发生器的MARX回路中接入电感线圈,可产生符合IEC 60060—3标准的振荡型冲击电压波形。     

国际贸易与SA8000标准

SA8000是一个关于企业社会责任方面的国际性标准。该标准的宗旨是促进企业在追求产量和经济效益的同时,必须重视相应的社会责任和社会利益。介绍了SA8000标准的主要内容和作用;评估了SA8000标准对我国出口贸易,尤其对劳动密集型行业出口贸易的巨大影响。     

冲击负荷对电能计量的影响

针对现场的电能计量纠纷,提出了冲击负荷对电能计量的影响问题,同时设计了一套实验方案,定量对冲击负荷对电能计量的影响作了分析,帮助现场解决了电能计量纠纷,由此提出电能表的响应速度应作为衡量电能表质量的一个重要指标的问题。     

220kV氧化锌避雷器泄漏电流超标的原因分析

针对某220 kV氧化锌避雷器泄漏电流超标的情况,对试验方法进行改进和理论分析,结合近年来避雷器的带电测试数据,排除避雷器不合格的可能性,找出避雷器泄漏电流超标的原因。分析发现造成220 kV氧化锌避雷器上节试验数据超标是因为试验过程中的杂散电流以及试验接线方法影响所致,并据此提出220 kV氧化锌避雷器试验的改进措施。     

配电网电容电流测量方法探讨

通常配电网电容电流是决定是否装设消弧线圈、确定消弧线圈容量和进行消弧线圈调谐的重要依据。本文归纳了配电网电容电流测量方法,详细分析了各种方法的测量精度、优缺点及适用范围,并提出了一种测量配电网电容电流的新方法:从电压互感器开口三角侧注入两个变频恒流信号,寻找系统谐振频率,计算出配电网对地电容和接地故障电容电流。实验证明,该方法不需改变配电网一次接线,不影响配电网正常运行,具有安全、简捷、准确等特点。     

High-voltage testing on UHV equipment: Overshoot and base curve for oscillating lightning impulse

As the higher impulse testing voltage, residual inductance of the test circuit or the stray capacitance of the test object increases with size. This means that the overshoot superposed on standard lightning impulse voltage would not be neglected because of its larger value during the lightning test. This paper describes the analysis of overshoot and oscillation based on the equivalent circuit containing a residual inductance. The waveform parameters such as relative overshoot magnitude, oscillation frequency are also derived to evaluate the influence of the residual inductance in the impulse testing circuit. The oscillating impulse waveform is related to the base curve of the standard lightning impulse. Furthermore, the base curve for oscillating impulse is proposed by the analysis. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

用于压敏电阻的半波冲击电流自动测试系统

用正弦半波(正或负)为高压电源,利用微机和PLC、MPT为控制单元,研制了用于压敏电阻通流空量试验的半波冲击电流自动测试系统。该系统可对压敏电阻进行不同模式(下、负或正负交替)的冲击试验,测试试验中的电流、残压以及能量,并可存储试验数据及在线显示试验状态和试验波形,具有试品好坏判别功能,测试速度高达2~3片/s。