Field test of 275-kV internally water cooled XLPE cable system

A 275 kV internally-water-cooled XLPE power cable with a stainless steel coolant tube and a wire shield was developed that greatly reduced the consumption of ion exchange resins and the sheath eddy current loss, respectively. A 230 m cable system which included the cable, cable accessories and cooling facilities was constructed, and a field test was carried out over a two year period. The long-term stability and reliability of the cable system were confirmed by the field test and a subsequent residual performance test. The practicality of the cable system was further ensured by developing novel methods of system recovery from faults     

Development of radial-flow type internally oil-cooled oil-filledcable

A radial-flow type, internally oil-cooled, oil filled, paper-insulated cable has been developed. The oil flows radially through the paper insulation, decreasing the thermal resistance of the insulation. The decreased thermal resistance as well as the cooling effect of the oil flow in the central oil duct and the outer oil duct under an aluminum sheath increase the current capacity. A method for calculating the cooling characteristics is introduced. The results of initial electrical tests and a long-term field test, confirming the stability of the cable and accessories, are presented     

Operation control of internally conductor cooled cable system

The development of 275 kV internally-conductor-cooled cable systems is under way for application to long-distance large-capacity (1500 MVA/cct) underground transmission systems. From the viewpoint of the reliability and the energy economy of these systems, the operational control system for the cooling facilities is especially important, because the facilities require large cooling capacity due to the large heat loss of the cable conductor. The cooling device characteristics are described, and the effects of operation control on energy savings are examined. A long-term field test has shown that the computer-controlled operation system is very useful. Simulation results for the operational control system confirm that calculated values are in good agreement with measurement results     

Development of 500 kV DC PPLP-insulated oil-filled submarine cable

This paper outlines the development of a 500 kV DC oil-filled submarine cable capable of transmitting 2800 MW with ±500 kV 2800 A bipole system. Polypropylene laminated paper (PPLP) was employed as the insulation material, which is the world's first application to DC cables. The conductor size is 3000 mm², which is the largest size for submarine cables ever put into practical use. Through various fundamental and prototype tests, the cable proved to have excellent electrical characteristics for DC voltage as well as transient overvoltage. The cable and accessories are undergoing a long-term accelerated aging test as the final confirmation of their reliability and stability     

我国首套高温超导电缆并网运行情况

高温超导电缆具有传输容量大、损耗低、无污染、占地空间小等优点,有助于解决城市电网中日益增长的电力需求问题.近年来高温超导电缆技术在中国取得了巨大的发展,文中介绍了已于2004年5月在云南普吉变电站并网运行的我国首套高温超导电缆系统的运行情况,包括电缆系统参数、电缆本体、终端、冷却系统、监测与保护系统等.这套高温超导电缆系统的成功并网运行意味着中国的高温超导电缆技术已向工业化生产迈出了重要的一步.     

采用水冷却系统提高隧道内电缆输送容量的研究

对于电缆来说,由于电缆本身结构及敷设方式和环境的限制,造成电缆的输送能力提高比较困难。为解决上述问题有必要采用电缆扩大容量的措施。电力电缆大容量化方案很多,但从目前状况看导体大截面、降低交流电阻、降低介质损耗等手段目前经过多年的研究,技术上基本已达到极限,很难期望近年会有重大突破;在现阶段,采用强迫水冷却为一种相对造价低廉、效益好的方法。本文通过对隧道内高压电缆水冷却系统的建模分析及计算,结果表明电缆采用外部水冷却方式对电缆载流量的提高是十分显著的,在实际工程中有应用价值。同时本文亦对水冷却系统的组成、占用空间及运行维护等工程实际问题进行了探讨,为今后工程中的实际应用做了技术储备。     

Development of 500 kV dc PPLP-insulated oil-filled submarine cable

This paper outlines the development of a 500 kV dc oil-filled submarine cable capable of transmitting 2800 MW with a ±500 kV 2800 A bipole system. Although polypropylene laminated paper (PPLP) has been employed as ac cable insulation material, this is the world's largest first application to dc cables. The conductor size is 3000 mm², which would be the largest size for submarine cables. Various fundamental and prototype tests have proved that the cable has excellent characteristics electrically as well as mechanically. The cable and accessories are currently undergoing a long-term accelerated aging test as a final confirmation of their reliability and stability. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120 (3): 29–41, 1997     

利用以太网和ATM技术实现电网运行状态实时监测

针对当前电力系统动态安全监控系统中相角测量装置(PMU)数据传输时延大、系统规模有限的现象，利用计算机网络在数据传输中的准确性和高波特率性，采用以太网和异步传输模式(ATM)相结合的方式，通过全光纤通道，构建了一套高实时性的全网相角信息实时传输通道。在工程中，该系统实现了一个周期上传一次数据，从而可实现在PMU广域测量数据基础上对电网的运行状态进行实时监测。     

配电网电缆屏蔽层宽带载波通信技术

稳定可靠且经济的通信系统是配电自动化系统实施的基础.针对城市以电缆为主供电的配电网特点,提出一种基于配电网电缆屏蔽层的宽带载波通信技术,其物理层通信速率可达30 Mbps,支持TCP/IP协议,可实现对等通信方式.通过对线路输入阻抗和载波通信频谱的测量分析,配置了相应的通信模式,在小陆家嘴地区的实际通信试验表明了该方式的有效性.     

基于物联网的110 kV电缆管井智能监测系统建设与应用

电力电缆在城市供电系统中起关键作用,电缆管井用于电缆接头制作或检修施工使用。日常运行过程中,电缆管井可能会出现电力电缆本体或中间接头过热,环境温度过高、水位过高等异常状态,大量非正常烟雾及非法入侵等现象也威胁着电缆供电系统的可靠性。介绍了一套用于对110 k V电缆管井智能监测的系统,包括智能感知系统、监控主机系统及在线监测终端系统。首先,介绍了由多智能传感器组成的感知系统,通过Lo Ra技术同井上监控主机无线通信,数据推算及实际测试结果表明本套系统依靠电池能够满足长时间续航要求;然后,介绍了多功能后台远程监测终端系统,后台系统基于物联网NB-lo T技术无线连接远端监控主机。本套系统在深管井中得到应用,能实时感知系统运行健康状况,极大便利运行维护人员,对确保电力电缆安全运行,提高供电可靠性具有重要意义。     

一种大功率冷却型直流充电桩电缆的研制

介绍了一种35 mm2大功率冷却型直流充电桩电缆。通过调整线缆结构,增加循环冷却管,对主动力线芯进行直接冷却,从而达到导体截面积不变的情况下,充电功率高达350 kW,充电电流高达450 A,充电时长仅15~20 min,大幅度缩短充电时间,减少充电等待。     

浅析南非标准中中压电缆的长期老化试验方法

为满足南非国家标准SANS 1339:2010的要求,证明中压交联聚乙烯绝缘电缆的绝缘材料的长期稳定性和抗水树性,中压电缆的长期老化试验已被逐渐重视并采用.根据南非试验方法标准SANS 6284-5:2007要求设计了长期老化试验系统,并得到了南非国家标准局的认可.     

变电站实时数据网络化传输的可行性

文章针对变电站多种实时数据远传各类主站系统运行中存在的问题，以及对实时数据需求的增长，提出了在变电站实时系统和各主站系统之间构筑网络化传输的新模式，即基于2M光纤组建的传输控制协议/网络互联协议（TCP/IP）通信网，采用IEC 60870-5-104网络远动规约，构筑的电力自动化信息数据的网络传输模式。文章分析了该模式的特点和优势。该模式已在厦门电业局得到实际应用，效果良好，验证了该模式的可行性。     

高温超导输电电缆的现状与发展

超导输电电缆具有截流能力大、损耗低和体积小的优点,是解决大容量、低损耗输电的一个重要途径。文章概括介绍了高温超导电缆的结构、电缆的损耗、低温冷却系统,以及中国科学院电工研究所等单位研制的75 m长高温超导电缆。文中还简要提出了高温超导电缆的应用领域和前景。     

三芯高温超导电缆室温及液氮温度机械性能研究

为研究三芯高温超导电缆在室温及运行温度(通常为液氮温度77 K)下的机械性能,对一根长度约为10 m的三芯超导电缆试样进行室温及液氮温度(77 K)下的机械拉伸试验,以及降温收缩试验.通过试验,得到了相应温度下的拉伸模量和降温收缩时电缆的收缩率,并将试验结果与铜衬芯及单芯超导电缆试样的相应试验结果进行比较.结果表明,三...     

XLPE cable technology for operating voltages of 245 kV and above

The sources of losses, their effects on cables sizing, how they are affected by load growth rates and load shapes, and the economic evaluation of losses are discussed. A slightly different type of loss, the energy costs for operating circulating and cooling equipment for forced-cooled cable systems, is also addressed. Unified consistent methods for the cable engineer and system planner to evaluate the magnitude of losses on a cable system and the costs of those losses are developed. Detailed analyses of the transmission and distribution system addressing the technical and the economic impact of losses is provided     

高温超导电缆冷却系统维保研究

目前,高温超导电缆冷却系统在维保工作方面无过多的借鉴经验,一般需长时间运行探索才能总结出更适合每套系统的维保工作方法。本文以百米冷绝缘结构高温超导电缆为例,通过对高温超导电缆系统运行的长时间探索和经验积累,总结了一套在低温常压状态下实施维保工作的方法并实践证明了可行性,顺利完成了维保工作。从效果看改观明显,确保了高温超导电缆系统持续、安全、稳定运行。     

基于振动特征的智能电缆防外破监测技术研究

电力电缆是城市输配电系统的重要组成成分,其运行状态关系着城市供电的可靠性。近年来,因施工、偷盗、改造引起的电缆外力破坏问题长期威胁电缆运行安全,但由于电缆分布广、运行环境复杂,目前缺乏有效的监测和预警方法,传统的在线监测系统因其改造成本和维护难度较大,且难以在城市电缆系统中实现主动预警。本文首先基于压电传感器研制了无线分布式的电缆外力扰动智能传感器,并对其数据处理、低功耗电源管理、取能单元以及物联网通讯方法进行了分析;通过典型外力激励下电缆振动试验,获得了电缆振动信号的时域特征和时频域特征,并提取了可用于外力扰动识别的特征参量,为建立基于物联网的分布式电缆防外破智能预警系统鉴定基础。     

Feasibility study of compact high-Tcsuperconducting cables

A conceptual design of a compact high-T_c superconducting cable was developed by using the Bean model. The experiments suggested that the Bean model provides a rough evaluation of hysteresis loss in high-T_c superconducting wires, which is supposed to be the main component of AC loss. A compact high- T_c superconducting cable was designed using a method based on the Bean model so that it could be installed in existing cable ducts. The results indicated that a compact high-T_c superconducting cable system can increase the power transmission capacity without the need to construct new cable ducts or tunnels. It has also been found that the high-T_c superconducting cable system is acceptable with regard to such system aspects as stability and short-circuit capacity     

Development of water pipe cooling system for power cables intunnels

A full-size test line was constructed to study the water pipe cooling system for a bulk-power transmission line installed in a tunnel. Based on the test data and their analysis, a technique for designing the system has been established. The results have indicated an effective layout of the cooling pipes in the tunnel, and have validated the accuracy of the computer models to determine thermal characteristics of the tunnel system. An efficient control method to operate the cooling system according to the load changes of the cables was developed. The chosen layout is shown to be more effective than the dispersed layout because it accelerates the air convection and makes the air temperature more uniform. Furthermore, the thermal convection resistance between the tunnel wall and the air is reduced. It was also verified that the air temperature distribution along the vertical shaft could be predicted by thermal convection analysis. This cooling system is scheduled to be applied to a 154 kV power cable line in 1990