共查询到20条相似文献,搜索用时 187 毫秒
1.
2.
针对输电线路感应电压较高的特点,介绍几种高感应电压输电线路定相及绝缘试验方法,并进行分析比较.现场实测分析表明,降低感应电压后直接用兆欧表的测试方法对人身和设备安全都有保障. 相似文献
3.
针对输电线路在雷击情况下对同走廊并行油气管道的电磁干扰问题,结合500 kV同塔双回输电线路的运行参数,利用电磁暂态仿真程序ATP-EMTP建立输电线路与油气管道相结合的雷击暂态时域模型。在计及冲击电晕的前提下,仿真分析电晕损耗、雷击位置、雷电流幅值、管线距离、土壤电阻率及管道参数等因素对油气管道电磁干扰的影响。计算结果表明:电晕损耗使管道暂态电压发生衰减和畸变;落雷点及雷电流幅值对油气管道电磁干扰影响较大;管线距离与管道电磁干扰呈负相关;土壤电阻率及管道参数对管道电磁干扰影响较小。 相似文献
4.
5.
1000kV同塔双回线路感应电压和电流的计算分析 总被引:1,自引:0,他引:1
同塔双回输电线路在一回运行、一回检修时,检修回路及地线中会产生感应电压、电流。使用EMTP仿真计算了1 000 kV交流特高压同塔双回输电线路1回线路停运检修时,运行回路对检修回路和地线的感应电压、电流,并对输电线路和地线上的感应电压、电流的影响因素进行了分析。可为特高压同塔双回线路检修及带电作业等方面的工作提供参照依据。 相似文献
6.
7.
8.
9.
750 kV同塔双回输电线路中感应电压、感应电流的研究以及接地开关的选取 总被引:1,自引:0,他引:1
同塔双回输电线路中,当一回线路正常运行、另一回线路停电检修时,由于2回输电线路间的静电感应和电磁感应作用,在检修回路中会产生感应电压和感应电流.为确保运行检修时的可靠性和安全性,要求线路上采用的接地开关必须具有开合感应电流的能力.推导了接地开关在4种工况下感应电压和感应电流的大小,利用EMTP计算了750 kV电压等级同塔双回线路的感应电压和感应电流以及开关接地时所产生的瞬态恢复电压(TRV)的大小,为750 kV电压等级接地开关的选型提供了依据. 相似文献
10.
用EMTP仿真计算了淮南~皖南一浙北~沪西1000 kV交流同塔双回线路架空地线感应电压和感应电流,并对架空地线上的感应电压、电流的影响因素进行分析.具体仿真计算得出大、小运行方式下不同运行状况的特高压同塔双回线路架空地线的感应电压、电流的幅值.分别仿真分析了相序排列、地导线间距、线路负荷以及绝缘地线分段长度等因素对架空地线感应电压、电流的影响.研究结论可为特高压输电线路检修与带电作业,以及感应电压、电流的利用等方面的工作提供借鉴. 相似文献
11.
12.
13.
A method is developed for calculating the induced voltages on fence wires/pipelines underneath AC power transmission lines. The method is based on the charge simulation technique and takes into account the disturbances of the electric field and potential due to the presence of the fence wire/pipeline underneath the line. The calculated values of the induced voltage on fence wires are compared with those measured before. Induced voltages on pipelines underneath 230- and 380-kV lines are measured, correlated to the calculated values and discussed in the light of electric field induction on objects adjacent to AC power transmission lines 相似文献
14.
There will be more and more AC transmission lines near oil/gas pipelines in the future.So in order to determine the safe distance between them,simple and effective methods are required for engineers to efficiently evaluate the electromagnetic effect on oil/gas pipelines due to faults of AC transmission lines.In this paper,an easily handled fitting formula is obtained based on multiple calculation results,which is the maximum voltage on the pipeline anticorrosive coating produced by 1 000 kV AC transmission line under single phase ground fault.Although the calculation results obtained from the fitting formula differ from those gained by precise calculation with softwares,the verification of the formula shows that it is applicable for engineering calculation.This research could be applied to evaluate the electromagnetic effect of 1 000 kV AC transmission line under single-phase ground fault on nearby pipelines,as well as to determine the safe distance or the maximum parallel length. 相似文献
15.
由于共建城市地下走廊,输电线路常与天然气管道并行敷设,当输电线路遭受雷击时,通过杆塔接地网向附近土壤散流会导致邻近天然气管道损耗的问题。为了研究雷击输电线路对天然气管道的具体影响,本文通过COMSOL Multiphysics仿真软件建立临近管道处杆塔辅助接地网散流模型,对比分析了杆塔辅助接地网的外延长度、面积、敷设方向、连接线数量以及土壤电阻率等因素对杆塔接地电阻和天然气管道电压峰值的影响,进而提出了基于杆塔辅助地网的管道过电压防护方案。仿真结果表明:减小土壤电阻率、增加辅助地网外延长度、面积和连线数量会降低天然气管道感应电压峰值;135°敷设辅助地网对天然气管道感应电压峰值防护效果最优。本文研究结论可为城市综合能源走廊建设提供参考。 相似文献
16.
17.
18.
This paper diagnoses the corrosive effects of the electromagnetic induction caused by double circuit high voltage power lines (HVPL) on the buried X70 steel pipelines. To achieve this objective, firstly the electromagnetic interference between the double circuit HVPL and the X70 steel pipeline (the distribution of the magnetic field and the induced AC current densities in the buried X70 steel pipeline) and the factors affecting this interference such as the vertical distance between the double circuit HVPL and the X70 steel pipeline, and the conductor phase sequence orientation were studied. Then, electrochemical measurements were used to characterize the corrosion polarization properties of X70 steel in simulated soil at various AC current densities. The results show that with an increase in the AC current density, the corrosion rate of the X70 steel increased, indicating that the induced AC current density has accelerated the corrosion degree of X70 steel, by comparison with that in the absence of the AC current density. We can conclude from these results that the electromagnetic induction caused by the double circuit high voltage power lines affects the electrochemical characteristic of the X70 steel pipeline and accelerates the corrosion of the pipeline. 相似文献
19.
由于传输走廊紧张,我国架空输电线路建设与输油输气管道常平行或交叉架设。“两线一地”电磁干扰问题、管道安全与防护是热门研究课题,但有关雷击输电线路时临近管道感应过电压的研究较少。文中采用电磁分析软件CDEGS建立简化的杆塔-管道模型,分别针对线路与管道的间距、地质条件及杆塔接地网结构对管道的电磁干扰影响进行仿真,计算分析输电线路杆塔迫近油气管道情况下管道防腐层雷电过电压的影响因素和防护效果,给出管道过电压防护的相关施工建议。研究结果可为输电线路及油气管道“两线一地”综合能源管廊建设和技术改造提供参考。 相似文献
20.
交流架空输电线路与钢制埋地管道共用走廊资源的现象越发频繁,短时大电流入地时产生的阻性耦合电压将会严重加速管道腐蚀。为量化计算埋地管道阻性耦合电压,文中提出一种基于CDEGS仿真模型的计算方法。首先建立大电流入地仿真模型;其次给出工频电流接地时管道阻性耦合电压的计算方法,并分析电流幅值、土壤电阻率以及电流入地点离管道最近点的距离对管道阻性耦合电压的影响;最后给出雷电流入地时,计及频率的管道阻性耦合电压的计算方法以及基于时频转换的电压最大值计算方法,并分析雷电流幅值、雷电流入地点离管道最近点的距离、土壤电阻率以及雷电流经多杆塔入地对管道阻性耦合电压的影响。 相似文献