超高压输电线路架设跨越高速公路施工技术探讨

随着电力事业的不断推进，超高压输电线路架设工作日益复杂化，特别是对于超高压输电线路架设跨越高速公路施工来说。然而，我国超高压输电线路架设跨越高速公路施工与西方发达国家存在着一定的差距，为了适应不同的输电线路架设环境，需要我们对超高压输电线路架设跨越高速公路施工技术加以研究。因此，我们需要在不同架设适用条件进行分析的基础上，对强度、封顶网和跨越架进行计算，从而制定超高压输电线路架设跨越高速公路施工技术措施。     

浅谈超高压输电班组的管理

超高压输电线路主要负责从发电厂向电力负荷中心输送电能或电力负荷中心互相联络调配的长距离线路,目前我是我国供电的主网架。超高压输电线路由超高压公司（局）下属输电班组运维。所以班组管理的质量直接影响输电线路的健康水平。     

超高压输电线路施工中海拉瓦技术的应用

本文探讨了海拉瓦技术在超高压输电线路现场施工的应用,建立了基于海拉瓦技术的输电线路现场施工技术应用平台,为超高压线路施工方案设计、施工组织和管理提供了有效的技术支持,提高了线路施工管理的科技含量和施工效率。     

超高压输电线路状态检修的应用研究

为了保障超高压输电线路的运行状态稳定,本文从状态检修的必要性、线路状态的监控、设备状态检修管理系统,以及计算机系统在状态检修中的应用这四个方面对超高压输电线路状态检修的应用进行研究。     

输电线路在线巡视系统的智能预警系统分析

随着我国电力系统的不断完善以及相关科技水平的不断提升,国内对电力的依赖不断增强,对输电线路的供电的可靠性和安全性的要求日益提高。智能预警的系统是输电线路进行在线巡视所使用的一种新型技术,可以有效的提升输电线路的稳定性与安全性。本文对输电线路的智能预警的原理、预警系统任务以及输电异常的辨别进行了详细的分析,对有效提升输电线路的安全性具有重要指导作用。     

浅析输电线路安全稳定运行措施

随着社会快速发展，我国电力系统的输电线路和超高压电力输电线路的逐渐增多，输电线路是供电系统的命脉，一旦发生故障．则可能影响到几片区域的供电安全，甚至造成不可估量的损失，因此，预防输电线路故障历来是供电系统的一项重要工作。为保证输电线路安全经济稳定运行，必须采取有效的预防措施.     

送变电企业承担超高压输电线路运行检修的优势

本文以贵州送变电公司参与输电线路运行检修工作为例,讲述了送变电企业承担超高压输电线路运行检修的优势。     

探析500kV输电线路的检修措施

500kV输电线路属于超高压输电线路,如果超高输电线路在输送途中出现问题的话,就会对整个电力系统的正常运转产生极大的影响。对于500kV输电线路在输送途中可能出现的问题,我们采用调查和对比的方法来让问题的定位和检修变得更方便,本文就此问题做了具体分析。     

1000kV特高压架空输电线路工程紧线施工工艺探讨

主要研究1000kV特高压架空输电线路工程紧线施工工艺,介绍了超高压架空输电线路紧线原则、工艺流程,详细讨论了预紧线和紧线施工工艺。     

浅析提高超高压输电线路巡视质量的方法

超高压输电线路输送电能距离较长,多为跨区域送电,目前是我国电网结构的主网架。线路途经地区多为荒郊野外、高山大岭,周围自然环境复杂,设备本体安全运行受到很大考验。随着我国基础设施建设力度不断加大,施工单位在线路附近或保护区内违章施工作业造成的事故比例逐年增加。超高压输电线路目前主要以传统的人工巡视为主,配以一年一次或两次直升机低频次巡视。所以,提高人工巡视质量是提高线路健康水平和减少事故发生的有效途径。     

高压线下石质路堑开挖控制爆破施工实践

在通电超高压线下进行路堑开挖爆破作业,必须保证高压线路和铁塔的安全,对爆破振动和飞石控制严格,爆破设计和施工难度较大。介绍了该复杂环境下控制爆破方案设计、爆破参数选取和安全防护措施;并对爆破效果进行了分析,得到了一些有益的经验。     

基于TRIZ的防雷绝缘子封装结构的设计

目的 研究和开发一种具有绝缘子和避雷器双重功能的新型防雷绝缘子。方法 应用TRIZ理论在线路避雷器的基础上进行改进研究,通过采用功能分析、因果链分析、矛盾分析等工具进行创新设计。结果 运用TRIZ创新方法产生了7种封装结构件的力学性能增强方案,2种封装结构设计方案和1种集成绝缘子和避雷器双重功能的设计方案,综合筛选出了1个最优的防雷绝缘子的设计方案。结论 所设计的新型防雷绝缘子仅通过优化封装结构设计便可集成绝缘子和避雷器的功能,可以在线路正常运行工况下发挥绝缘子作用,而在过电压状态下激活避雷器立即将电压钳位,从而保护输配线线路免遭破坏;设计方案简单有效,对提高输配电防雷可靠性,降低安装、运维成本具有重要意义。     

Electromigration in layered Al lines studied by in-situ ultra-high voltage electron microscopy

In-situ side-view transmission electron microscopy (TEM) observations of electromigration in Al-on-TiN lines with a drift velocity measurement structure have been carried out using an ultrahigh voltage (2 MV) electron microscope. Thick chips as-diced from silicon substrates served as TEM samples. The observations revealed the dynamic behavior of electromigration-induced voids and hillocks during forward and reverse current feeding through the Al lines. The results include vertical growth of voids bounded by faceted Al, refilling of voids, void growth in a hillock upon current reversal, and whisker growth.     

自立式双回路铁塔送电线路导线断裂后的结构动响应分析

为了研究机械性故障对自立式双回路铁塔输电线路结构的受力影响,建立了500kV架空输电线路耐张段的耦合体系模型,采用瞬态动力分析方法计算了高压交流输电线路耐张段一基塔在发生上横档一组导线突然断裂破坏后,邻近破坏处的导线、绝缘子、塔构件的瞬态动响应变化规律。分析结果表明,上横担一组导线断裂失效对邻近端导线张力峰值没有明显影响,对邻近端的绝缘子及铁塔横担构件的受力有较大的影响。研究成果可为输电线路结构设计提供理论依据。     

高压输变电设施低频噪声特性研究与限值的确定

通过高压输变电设施现场的测试,剖析变电站设备和高压输电线路的噪声等级及频谱特性。利用语义细分法和等级评分法对典型输变电设施噪声进行人体感受调查试验。提出高压输变电设施低频噪声限值,为未来参与制定科学的低频噪声环保限值标准提供依据,具有一定的社会和经济意义。     

Microstrip delay line phase shifter by actuating integrated ground plane membranes

The design, simulation, fabrication, measurement and performance of a V-band micro- strip delay line phase shifter using electrostatically actuated integrated micro-machined ground plane membranes are presented. The microstrip line is etched on an RFIC-friendly silicon substrate. The membrane is made of aluminium micro-ribbons and is fabricated on the ground plane side of the silicon substrate. The actuation of the ribbons away from the transmission line introduces an air gap between the radio-frequency (RF) substrate and the ground plane. By controlling the air gap thickness, a controllable phase shift in the transmission line is obtained. Each micro-ribbon measures 3.20 mm in length, 20 mum in width and 1 mum in thickness. A measured phase shift of 41deg at 50 GHz was achieved with an actuation voltage of 120 V. The fabrication process added a 20 mum initial air gap between the micro-ribbons and RF substrate, increasing the required actuation voltage for a given phase shift. The simulated phase shift results agree well with the measurements.     

A Digital Directional Coupler With Applications to Partial Discharge Measurements

This paper presents a digital directional coupler (DDC) that separates forward- and backward-traveling waves on a transmission line. Based on two independent wideband measurements of voltage and current and on frequency-domain digital wave splitting using a fast Fourier transform (FFT), the DDC is a versatile device for direction separation. A practical procedure is described for the calibration of the digital processor with respect to the particular transmission line and the voltage and current sensors that are being used. As an experiment, a DDC was designed and implemented using low-cost wideband sensors and was installed with medium-voltage equipment in a power distribution station. Partial discharge (PD) measurements were conducted on cross-linked polyethylene (XLPE)-insulated power cables to illustrate the directional separation capabilities of the DDC.     

Transmission line protection with thin film chalcogenide glass devices

We present the theoretical analysis of a lossless transmission line excited by voltage pulses of the type associated with high altitude nuclear explosions or with lightning. The line is protected by a thin film chalcogenide glass ovonic threshold switch (OTS). The OTS is very simply modelled as a lumped parameter network, and its OFF-ON transition is represented by a time-varying resistance which is characterized by a time constant τ. The analytical solution for the voltage transients along the line considers the applied voltage pulse as a succession of narrow component pulses whose effect is computed according to the value of the time-varying reflection coefficient at the device location. The analytical solution includes the effect of multiple reflections, and it is evaluated numerically so as to determine the voltage profile along the line. We show that the OTS device is well suited for electromagnetic pulse line protection. The effects of the delay time and of the values of the OFF and ON resistances of the switch are discussed.     

Space vector-based analysis of overmodulation in triangle-comparison based PWM for voltage source inverter

The equivalence of triangle-comparison-based pulse width modulation (TCPWM) and space vector based PWM (SVPWM) during linear modulation is well-known. This paper analyses triangle-comparison based PWM techniques (TCPWM) such as sine-triangle PWM (SPWM) and common-mode voltage injection PWM during overmodulation from a space vector point of view. The average voltage vector produced by TCPWM during overmodulation is studied in the stationary (a–b) reference frame. This is compared and contrasted with the average voltage vector corresponding to the well-known standard two-zone algorithm for space vector modulated inverters. It is shown that the two-zone overmodulation algorithm itself can be derived from the variation of average voltage vector with TCPWM. The average voltage vector is further studied in a synchronously revolving (d-q) reference frame. The RMS value of low-order voltage ripple can be estimated, and can be used to compare harmonic distortion due to different PWM methods during overmodulation. The measured values of the total harmonic distortion (THD) in the line currents are presented at various fundamental frequencies. The relative values of measured current THD pertaining to different PWM methods tally with those of analytically evaluated RMS voltage ripple.     

行波效应对大跨越输电塔－线体系纵向地震响应影响

由于特高压大跨越输电塔－线体系塔身高跨度大,仅考虑单塔及塔－线体系的一致地震输入是远远不够的。本文考虑地震波沿大跨越线路传播时引起的地震行波效应,建立了特高压大跨越输电塔-线体系精细的三维空间有限元模型,运用几何非线性动力时程分析方法研究了纵向地震作用下大跨越输电塔－线体系的地震响应特性,并和一致地震动输入下的反应进行了对比。结果表明：行波效应既可以增加又可以减小塔身的地震响应,主要与地震动作用于大跨越两端输电塔的相位差有关;行波效应对导线跨中竖向位移响应影响十分明显,但对导线内力响应影响很小