交联聚乙烯电缆局部放电检测技术

主要探讨用高频宽带电磁耦合法检测交流聚乙烯绝缘电力电缆的局部放电。运用数学中的分形学自相似和分数维原理,提出全新概念的交联聚乙烯绝缘电力电缆局部放电在线监测、在线巡测技术。     

Cost-effective on-line partial discharge of measurements for cables

On-line partial discharge (PD) measurements are an efficient method for detecting certain insulation defects of cables. These include defects in cable joints and terminations, and defects due to mechanical impact. Noninvasive, efficient, and widely applicable, portable on-line PD measurement techniques are strongly favored by the electricity industry. Three on-site PD measurements for cables are described in this article to illustrate how the techniques achieve cost-effective insulation diagnosis to protect the main assets.     

急于局部放电频谱分析的XLPE电力电缆在线检测技术

基于局部放电频谱特性分析，本文提出在甚高频（VHF）检测XLPE电力电缆的局部放电量，并研制出可应用于XLPE电力电缆运行状态现场在线 检测新技术。试验结果表明：该技术在10kHz-28MHz频率范围内检测XLPE电力电缆本体或附件中小于1pC的局部放电信号。     

振荡波电压法检测10 kV电缆局部放电试验

介绍了振荡波电压法测试系统的主要原理、设备构成及局部放电定位技术的原理;基于振荡波电压法检测技术,通过在一条退运10 kV交联聚乙烯短电缆上人工设置各种模拟缺陷,对系统的检测效果进行了初步分析,得出振荡波电压法对某些类型的缺陷如错用绝缘胶带等效果十分明显,而对其他一些缺陷如压接管表面存在毛刺等效果有待进一步研究;研究也表明电缆终端缺陷的检测可能会由于高压线夹表面放电引入干扰受到影响,建议采取其他辅助检测手段如开关柜局部放电检测技术或对高压线夹进行防电晕处理。     

基于COM组件技术的XLPE电缆局放检测系统开发

对XLPE电缆的局部放电进行检测是评判该电缆绝缘状况的重要方法之一.采用MATLAB与VB混合编程设计电缆局放检测系统,既能满足系统直观可视性的要求又能解决大量的数据分析、谱图显示问题.介绍整个电缆局放系统的软硬件结构、COM组件技术、COM组件技术在系统中的应用实例.     

Service aged 69 and 115 kV XLPE cables

Five 69 kV XLPE cables, 6 to 23 years in service and two old vintage cables from storage plus a 115 kV XLPE cable from service together with a spare cable from the same production, kept in storage, were evaluated. All components of the cables were found to show little signs of deterioration except for AC breakdown. The 69 kV XLPE cable from service has breakdown levels ranging from 10.2 to 18.2 kV/mm, the spare cable 15.0 to 17.7 kV/mm compared to 27.2 kV/mm, the only previously reported value for a new cable. The 115 kV XLPE cable had a breakdown level of 16 kV/mm and the spare 10 kV/mm. The above cables are low-stress cables. Most modern cables operate at higher voltage stresses, taking advantage of cleaner insulations with smoother shields and moisture barriers. Caution is advised in using older, low-stress cables placed in storage     

35kV钢芯铝绞线交联聚乙烯架空电缆的设计

介绍一种以圆形紧压的钢芯铝绞线为线芯 ,以交联聚乙烯为绝缘的架空电缆的结构设计及计算 ,以满足35 k V大跨距架空线路的应用。     

用于XLPE电力电缆局放检测的宽频带电磁耦合法的研究

对用于 XL PE电力电缆局部放电检测的宽频带电磁耦合法进行了研究 ,针对带铁氧体磁芯的罗哥夫斯基线圈型电流耦合器 ,讨论了几个主要参数对其传递函数的幅频特性的影响。模拟实验和电缆局放测量表明 ,应用此电流耦合器来检测 XL PE电缆的局放是可行的     

500kV交联聚乙烯绝缘电缆绝缘结构研究

本文叙述交联聚乙烯 (XL PE)绝缘电缆绝缘统计设计方法。论述我国研制开发 5 0 0 k V XL PE电缆的绝缘结构采用绝缘统计设计方法的合理性。叙述我国 5 0 0 k V XL PE电缆的绝缘水平要求。论述对照日本已经运行的 5 0 0 k V XL PE电缆的绝缘结构参数和绝缘质量控制要求 ,采用绝缘统计设计方法 ,按相同可靠性原则作为我国 5 0 0 k V XL PE电缆确定电缆绝缘厚度和绝缘质量控制要求的基础是合理的。本文提出不同导体截面 5 0 0 k V XL PE电缆的推荐绝缘厚度。     

Research and development of ±250 kV DC XLPE cables

This paper describes the development of ±250 kV DC XLPE cables. Through a series of material investigations and the evaluation of model cables using two kinds of XLPE compound containing inorganic filler to suppress the accumulation of space charge within XLPE insulation, ±250 kV DC XLPE cables and factory joints were designed and manufactured. To check the DC electrical performance and reliability of ±250 kV DC submarine cable, electrical tests, mechanical test and long-term aging tests were performed. The test results showed that they had sufficient properties and reliability for practical use     

Performance characteristics of XLPE versus EPR as insulation forhigh voltage cables

The physical and electrical properties of crosslinked polyethylene (XLPE) and ethylene propylene rubber (EPR) are compared in the context of their use in transmission class cables. Results indicate that the 138-kV XLPE cable has AC withstand/breakdown strength at least 25% higher than the 150-kV EPR cable. The XLPE cable exhibits about 70% higher impulse strength than the EPR cable. The loss factor of the XLPE cable is at least 20 times lower than that of EPR cable. Thus with XLPE cables, the yearly energy savings can be on the order of 15 MWh/cct. km for a 69-kV system, 52 MWh/cct. km for a 138-kV system and 127 MHh/cct. km for a 230-kV system     

On-line partial discharge detection in cables

This paper describes an on-line PD (partial discharge) detection technique applicable to power cables. The method can be applied to both wire screen and solid shielded cables. In wire screen shielded cables, PD components with frequencies <100 MHz can be detected at distances over 150 m from the source, PD activity with levels as low as 20 pC can be detected within 100 m. However, in the case of solid shielded cables, PD levels of ⩾50 pC can be measured within 60 m in the frequency range <50 MHz. This method also can be utilized to check cable accessories such as splices and terminations. PD pulses with frequencies to ~300 MHz can be measured near the joints and terminations. The suitability and the sensitivity of the VHF technique were checked against two other alternative PD detecting techniques (pulse phase analyzer and high speed digital oscilloscope) by performing PD measurements in standard air gap and defects induced in EPR-insulated cable under laboratory-controlled conditions. The suitability and sensitivity of the VHF method were as good as the two alternative PD detection techniques     

Space charge behavior in full-size 250 kV DC XLPE cables

The space charge in full size 250 kV HVDC power cables was measured using the pulse-electroacoustic method. Measurements of two types of newly developed DC XLPE cables with 20 mm insulation were taken under a DC voltage of 500 kV with the conductor temperature at room temperature and at 85°C. A qualitative analysis of the space-charge distribution and a quantitative analysis of the electric fields in the vicinity of semicon interfaces were conducted. It was shown that the field in the vicinity of the inner semicon tends to increase by 10-40% when the polarity of the applied voltage was reversed, in the case when the conductor was kept at 85°C. However, the distortion of the electric field was significantly less than that expected in conventional XLPE cables. As the result, the subjected DC cables are considered to have stable DC characteristics from the viewpoint of space charge-behavior     

500kV XLPE电缆在宜兴抽水蓄能电站的应用

简要介绍500 kV XLPE电缆构造及特点、耐压试验及相关分析,借鉴相关电厂成熟经验,更安全稳定地将500 kV XLPE电缆应用于宜兴抽水蓄能电站。     

35kV交联电缆敷设试验与试验终端的应用

本文结合35kV交联电缆敷设试验过程中,因电缆端头处置方式不当对试验结果造成的不利影响,分析探讨了造成上述现象的原因,并提出了改进措施和方法。     

500kV XLPE电缆绝缘中树枝化现象的述评

介绍日本开发 5 0 0 k V XL PE电力电缆时研究树枝化现象的形成 ,评述 XL PE电缆形成电树和水树与场强的相关性、树枝引发场强和长期寿命特性的研究结果 ,说明由此确定 5 0 0 k V XL PE电力电缆的绝缘设计。     

110kV交联电缆及附件的现场变频谐振试验

结合实例重点介绍110kV交联电缆的变频谐振试验,论证试验的有效性,并提出变频谐振试验所需电源容量的估算方法,分析该试验方法的局限性,建议重点发展局部放电、红外成像等非破坏性试验。     

Editorial partial discharge measurements

The 29 papers in this special issue focus on the broad field of partial discharges, encompassing their mechanism, detection, measurement as well as their classification and locations in electrical apparatus and cables.     

10 kV交联聚乙烯绝缘电力电缆生产现状调研分析

本文通过对国内27家生产10kV交联聚乙烯绝缘电力电缆的主要生产企业的生产现状进行调研分析,对各生产企业的质量管理与控制体系、人力资源、生产及检测情况、原材料、生产工艺等五个方面进行全面的分析,并指出存在的问题,为生产企业进一点提高产品质量提供参考建议。     

XLPE电力电缆附件局部放电测量与分析

为研究XLPE电力电缆附件现场常见典型缺陷的放电特征,在3根电缆实体上分别设计制作了中间接头尖刺、主绝缘划伤和终端头应力锥错位3种放电模型,建立了基于PDBase的局部放电测量分析系统。对比研究了3种典型缺陷的局部放电特征,分析了放电次数相位分布谱图H_n(φ)、放电最大幅值相位分布谱图H_(qmax)(φ)和放电幅值分布谱图H(q)3种统计特征。试验结果表明,不同缺陷类型其放电发展过程不尽相同,呈现的PRPD谱图、单个脉冲波形、相位分布趋势及统计特征区别明显;而同一缺陷在相同条件下其放电特征呈现出相似规律且重复性好;这些特征为进一步开展电缆附件放电机理研究及放电类型的模式识别提供了有力的试验依据。