基于纤芯应变特征聚类的OPGW光缆风险辨识研究

为了解决在多重因素作用下难以准确评估OPGW光缆风险的状况,文章提出了一种基于纤芯应变特征聚类的OPGW光缆风险辨识方法。首先,分析了OPGW纤芯应变特征,包括OPGW光缆运行参数监测和OPGW纤芯应变相关参数特征。然后,以OPGW应力应变和布里渊频移为特征参数,采用初始聚类中心优化K均值聚类实现OPGW光缆风险辨识。算例结果表明,所提方法能够对OPGW的风险特性进行有效识别,有效支撑OPGW光缆的运行与维护。

Experimental investigation on de-icing by an array of impact rod-type plasma synthetic jets

Since flight accidents due to aircraft icing occur from time to time,this paper proposes an array of impact rod-type plasma synthetic jet de-icing methods for aircraft icing problems.The impact rod-type plasma synthetic jet actuator(PSJA)is based on the traditional PSJA with an additional impact rod structure for better de-icing in the flight environment.In this work,we first optimize the ice-breaking performance of a single-impact rod-type PSJA,and then conduct an array of impact rod-type plasma synthetic jet ice-breaking experiments to investigate the relationship between crack expansion and discharge energy,ice thickness and group spacing.The results show that the impact force and impulse of a single-impact rod-type PSJA are proportional to the discharge energy,and there exists a threshold energy Qmin for a single actuator to break the ice,which is proportional to the ice thickness.Only when the discharge energy reaches above Qmin can the ice layer produce cracks,and at the same time,the maximum radial crack length produced during the ice-breaking process is proportional to the discharge energy.When the ice is broken by an array of impact rod PSJAs,the discharge energy and group spacing together determine whether the crack can be extended to the middle region of the actuator.When the group spacing is certain,increasing the energy can increase the intersection of cracks in the middle region,and the ice-fragmentation degree is increased and the ice-breaking effect is better.At the same time,the energy estimation method of ice breaking by an array of impact rod-type PSJAs is proposed according to the law when a single actuator is breaking ice.

基于OPGW技术的输电线路外破灾害监测系统设计

输电线路大多架设在野外,受到外破灾害影响范围较大,为了提高输电线路安全,设计基于OPGW技术的输电线路外破灾害监测系统。以OPGW(光纤复合架空地线)连续盒为传感器,采用加装无线中继方式传输数据,设计杆塔终端,远程采集视频信息,设计视频监控结构,使用球形云台进行全方位输电线路监测,根据基于OPGW技术光缆的架设结构,设计OPGW全线逐塔接地方式,模拟无线通信功能,设计外破灾害监测流程。应用可知,该系统摄像头监测的角度范围,与实际监测的角度范围存在±15°的偏差,符合监测指标要求,且报警灵敏度高,感应时间短,有效地实现了输电线路外破灾害的广域监测。

基于OPGW光纤应变解析的矿区输电线路灾害监测系统

为解决复杂天气状况对矿区输电线路造成的外破灾害,基于OPGW光纤应变解析构建监控系统。利用被动式红外探测器组成环境监控模块,在矿区输电线路内部安装视频监控设备为球型摄像机,实现360°全视角监控,由ARM和DSP组成中央处理模块,与数据库信息进行匹配,实现数据分析。应用OPGW光纤应变解析技术分析光纤通信信号,确定输电线路受灾位置,并监测线路周围的移动目标、树木以及山火,在发现问题时,及时发出警报。实验结果表明,OPGW光纤应变解析技术得到的应变系数与原始数据基本吻合,能够很好地监测出被外破灾害影响的矿区输电线路。

基于COMSOL的OPGW雷击断股仿真

为了研究光缆结构的改变对光纤复合架空地线(OPGW)雷击断股的影响,应用COMSOL Multiphysics软件对雷击点局部进行仿真,通过仿真不同大小的雷击电流A、B、C分量以及改变架空地线的结构对OPGW进行雷击断股特性分析,以研究雷击电流分量和光缆结构变化对光纤复合架空地线雷击断股的影响。结果表明,雷击电流的A、B、C分量中C分量的破坏性最强,B分量破坏性最弱。在一定范围内增加铝包层厚度、OPGW层数以及内外股股数可以降低雷击后的最大温度,增强OPGW抗雷性能。

输变电工程中OPGW光缆敷设成本控制策略研究

随着信息技术的飞速发展,OPGW光缆作为通信传输的重要载体,在电力、通信等领域的应用日益广泛。然而,在OPGW光缆敷设项目中,成本控制问题一直是企业面临的重要挑战。有效控制成本关乎项目的经济效益,更是企业提升自身竞争力、实现可持续发展的关键所在。因此,本文旨在深入探讨输变电工程中OPGW光缆敷设成本控制策略,为企业在项目管理中提供有益的参考。

光纤复合架空地线OPGW防雷技术分析

通过深入分析各省市OPGW运行状态调查结果可知,光纤复合架空地线出现雷击断股的问题,多是由于铝合金股线的熔点较低,加之OPGW外径较小,使得雷击影响重大。本文以提高OPGW运行稳定性为研究目标,以雷电损伤类型为切入点,指出相关影响因素,提出可靠的防雷措施。研究结果表明,通过提升OPGW防雷技术水平,可彰显OPGW的线路防雷与通信的双重功能,降低线路维护成本。

瑞利散射信号的远距离OPGW光缆断纤定位研究

光纤复合架空地线(OPGW)容易因雷击、覆冰、烧损、断股而形成断纤故障,导致骨干电源与调度通信中断,威胁电力系统用电安全。随着光纤应用领域的逐渐扩大,大范围的断纤故障检测成为难题。提出基于广域测量的远距离OPGW光缆断纤定位方法。在瑞利散射原理的基础上,采集入射光子进入OPGW光缆核心结构时反射的瑞利散射信号。利用信号波形特征保留度最高的快速傅里叶变换,以消除瑞利散射信号噪声。通过相位调制器拟合瑞利散射信号在三维视角下的幅值波动情况,识别信号幅值大幅跌落的OPGW光缆断纤位置。利用幅值大幅变化的瑞利散射信号特征可以远距离捕获的特点,实现远距离OPGW光缆断纤定位。试验结果表明,所提方法定位距离远、精度高、效率高。通过所提方法的应用,可以及时准确地定位OPGW光缆中的断纤位置,帮助维护人员快速响应和处理故障,从而最大限度减少因断纤故障而造成电力系统中断的时间,提高电力系统的可靠性和稳定性。

微地形区OPGW地线不均匀覆冰计算模型改进方法

目前对均匀覆冰下架空线等值覆冰厚度计算模型的研究较多,但缺少对大截面、大单位长度重量的地线复合光缆(optical pilot ground wire,OPGW)地线覆冰的研究,特别是在微地形下等值冰厚计算模型的适用性。选取大档距大高差工况,通过有限元软件建立3种典型地形(山坡、山顶、垭口)下的3塔两档OPGW地线模型,结合考虑绝缘子串偏斜角的等值冰厚模型,对传统输电线路等值覆冰厚度模型进行误差分析,结果发现等值冰厚较小时大档薄覆冰情况下的传统冰厚计算误差较大。但随着平均等值冰厚增大,冰厚计算误差显著减小。利用以上分析结果和平均等值冰厚与绝缘子串轴向拉力与倾角的函数关系,提出一种冰厚误差优化计算方法,改进后的冰厚相对误差能控制在10%以内。

State of the art and practice of pavement anti-icing and de-icing techniques

Pavement snow and icing are worldwide problems, but effective countermeasures are just beginning to be developed in China. The two most common snow and ice removal methods are mechanical clearance and chemical melting, and the advantages and disadvantages of each approach are discussed here, including environmental and structural damage caused by corrosive snow melting agents. New developments in chemical melting agents and mechanical equipment are discussed, and an overview of alternative thermal melting systems is presented, including the use of geothermy and non-geothermal heating systems utilizing solar energy, electricity, conductive pavement materials, and infrared/microwave applications. Strategic recommendations are made for continued enhancement of public safety in snow and ice conditions.

Peridynamic modeling and simulation of thermo-mechanical de-icing process with modified ice failure criterion

De-icing technology has become an increasingly important subject in numerous applications in recent years.However,the direct numerical modeling and simulation the physical process of thermomechanical deicing is limited.This work is focusing on developing a numerical model and tool to direct simulate the de-icing process in the framework of the coupled thermo-mechanical peridynamics theory.Here,we adopted the fully coupled thermo-mechanical bond-based peridynamics(TM-BB-PD)method for modeling and simulation of de-icing.Within the framework of TM-BB-PD,the ice constitutive model is established by considering the influence of the temperature difference between two material points,and a modified failure criteria is proposed,which takes into account temperature effect to predict the damage of quasi-brittle ice material.Moreover,thermal boundary condition is used to simulate the thermal load in the de-icing process.By comparing with the experimental results and the previous reported finite element modeling,our numerical model shows good agreement with the previous predictions.Based on the numerical results,we find that the developed method can not only predict crack initiation and propagation in the ice,but also predict the temperature distribution and heat conduction during the de-icing process.Furthermore,the influence of the temperature for the ice crack growth pattern is discussed accordingly.In conclusion,the coupled thermal-mechanical peridynamics formulation with modified failure criterion is capable of providing a modeling tool for engineering applications of de-icing technology.

Dose-effect correlation of chloride de-icing salt on Euonymus japonicus

In order to prevent severe pollution by de-icing salt on greenery along urban roads, a half lethal dose （LD_50）for a plant population was confirmed through stress simulation of chloride de-icing salt on Euonymus japonicus, with an ianalysis of physiological changes, statistics on mortality rate on plant populations and mathematic modeling during a 30- day subacute toxicity test. The results indicate that a significant positive correlation in the early stages and a significant negative correlation in the later stages were observed between the amount of chlorophyll a and b in plants and a cumulative dose of de-icing salt. The amounts of free proline in plants and the dose of de-icing salt were positively correlated Over the entire period. No significant correlation in the initial stage, but a significant negative correlation in later stages was observed between the soluble protein and the dose of de-icing salt. LDs0 of this chloride agent on E. japonicus is 5 kg.（L·m2）-1 over 30 days.

基于OPGW技术的输电线路外破灾害监测系统设计

针对输电线路人工监测方式难以满足输电线路外破灾害监测需求的问题,引入OPGW技术,设计了一种新的输电线路外破灾害监测系统。设计主控模块,协调控制各功能模块,引入OPGW技术融合相关数据,采用超窄线宽激光源采集光纤振动反射信号,同时监测现场网络传输数据、远距离网络传输数据,完成输电线路外破灾害监测。实验结果表明,该系统能够同时监测区内故障、区外故障和外界干扰,很好地完成输电线路外破灾害监测。

基于OPGW光纤应变解析的输电线路外破灾害监测系统

为准确定义输电线路外破灾害的表现强度,实现对电网灾害行为的实时监测,设计基于OPGW光纤应变解析的输电线路外破灾害监测系统。处理暂存于存储器元件中的电量传输信号,调制参数,确定输电线路外破灾害表现强度,整合相关数据信息参量,建立完整的OPGW光纤应变解析表达式,设计输电线路外破灾害监测系统。实验结果表明,在OPGW光纤应变解析算法的作用下,输电线路外破灾害的表现强度准确定义能力明显提升,更符合实时监测电网灾害行为的实际应用需求。

智慧输电线路多业务共享OPGW接续技术及工程应用

随着智慧输电线路加快建设及新通信业务不断出现,如何构建安全可靠的信息通道成为亟待解决的重大问题。文章结合大芯数OPGW工程应用,提出多业务共享OPGW光纤接续点选择模型及算法,满足新业务装置对搭挂输电铁塔高度的特殊要求;研究直线塔改造为接续点的方法,满足搭挂光纤接头盒技术要求;研发分层结构可插拔光纤接头盒,实现多业务共享OPGW。研究成果在实际工程中成功应用,有效解决了OPGW投入运行后的接入难题和供需矛盾,为智慧输电线路等新业务近距离提供了安全可靠优质光纤通道,全面推广应用前景广阔,经济和社会效益显著。

雷击OPGW光缆对电力100G OTN系统影响分析

简要介绍了目前在电力骨干光通信网络中广泛应用的OPGW光缆的优缺点。电力通信OPGW光缆在雷雨天气较多的地区使用时,雷击OPGW导致光纤内所传输的光信号SOP剧烈波动,造成100G OTN设备误码。重点研究雷击OPGW对100G OTN系统的影响、雷击与SOP波动的关系、SOP波动对100G OTN系统及承载业务影响、主流厂家100G设备抗SOP性能对比及改进思路,并提出了电力100G OTN系统的设计建议。

Self-Structured Organizing Single-Input CMAC Control for De-icing Robot Manipulator

This paper presents a self-structured organizing single-input control system based on differentiable cerebellar model articulation controller (CMAC) for an n-link robot manipulator to achieve the high-precision position tracking. In the proposed scheme, the single-input CMAC controller is solely used to control the plant, so the input space dimension of CMAC can be simplified and no conventional controller is needed. The structure of single-input CMAC will also be self-organized;that is, the layers of single-input CMAC will grow or prune systematically and their receptive functions can be automatically adjusted. The online tuning laws of single-input CMAC parameters are derived in gradient-descent learning method and the discrete-type Lyapunov function is applied to determine the learning rates of the proposed control system so that the stability of the system can be guaranteed. The simulation results of three-link De-icing robot manipulator are provided to verify the effectiveness of the proposed control methodology.

基于COMSOL Multiphysics的OPGW耐雷性能分析与仿真

为了研究光缆结构的改变对光纤复合架空地线(optical fiber composite overhead ground wire, OPGW)雷击断股的影响,应用COMSOL Multiphysics软件对其雷击点局部进行仿真,通过施加不同大小的雷击电流A、B、C分量以及改变架空地线的结构,对光纤复合架空地线进行雷击断股特性分析。结果表明:雷击电流的A、B、C分量中C分量的破坏性最强,B分量破坏性最弱。A、B分量同时作用时,产生的最高温度高于单独A分量作用的结果。外股层半径每增加0.05 mm,仿真结果最高温度下降约20℃;外股导线半径每增加0.05 mm,仿真结果最高温度下降约25℃。仿真结果为优化光纤复合架空地线结构参数、提升耐雷性能提供了理论支撑。

一种OPGW光缆的绝缘引下接地装置

OPGW光缆三点接地起到为雷击电流和短路电流提供泄放通道的作用,提高光缆的抗风险能力,消除通信系统隐患,是切实保证电力通信系统安全稳定运行的重要措施。对此,以兰州公司信通公司所研发的OPGW光缆标准化三点接地装置为研究对象,探讨了一种OPGW光缆的绝缘引下接地装置。

500kV输电线路OPGW引下线弧光放电原因分析及防范措施研究

为分析500 kV输电线路光纤复合架空引下线对龙门架空气间隙击穿放电原因,结合空气间隙击穿原理,通过对放电点、接地网导通性及线路覆冰情况排查,发现光纤复合架空引下线覆冰,导致光纤复合架空引下线与龙门架之间的空气间隙不足,故障短路电流使光纤复合架空引下线产生高电压并对龙门架构架放电。最后提出新建工程引下光缆与杆塔或构架本体间距不小于50 mm,改造工程线夹之间新增长度不小于50 mm,电弧放电后应检查接地网完整性等防范措施。