高压电气设备绝缘状况的在线监测

随着我国各项事业的不断发展，电力在期间发挥着举足轻重的作用，高压电气设备绝缘状况的检测显得尤为重，本文介绍了高压电气设备绝缘在线监测的定义以及现有系统所存在的不足之处，并针对其中的主部分提出了详细的可行性建议，对保障我国高压电气设备的正常运行有重意义。     

电气设备的绝缘预防性试验研究

高压电气设备的绝缘预防性试验是为了对绝缘缺陷、绝缘性评估的重要技术措施,是保证高压电气设备安全运行的重要手段,其涉及的技术措施较多其基本原理也不尽相同,本文就绝缘预防性试验对高压设备的重要性、绝缘预防性试验的方法和原理和高压电气设备试验的安全管理进行简要的介绍。     

基于绝缘属性的高压试验细节分析

我国对高压电网发展的要求越来越高，也很急迫。电气设备由于长期的运作因此会产生一些问题，比如：绝缘系统被破坏。本文主要对高压设备的绝缘试验进行分析。     

基于SF_6气体绝缘金属封闭开关设备的研究应用

高压交流六氟化硫断路器(GCB)具有较高的可靠性能、合理经济的运行维护成本,在电力系统中应用广泛。本文通过对高压交流六氟化硫断路器的特点及类型介绍,对高压交流六氟化硫断路器设备中断路器、盆式绝缘子、三相共箱主母线等元件进行优化,对SF6绝缘电气设备分解产物在线监测系统研究以及对SF6气体绝缘件的设计研究三方面来具体介绍基于SF6气体绝缘金属封闭开关设备的优化研究情况。     

电气设备绝缘试验

电气设备绝缘试验是保证电气设备安全、可靠工作的检验手段,试验目的是为了及早发现绝缘缺陷,减少事故,确保电气设备安全、可靠地运行。本文主要论述了电气设备的绝缘缺陷、高压绝缘的试验方法等进行论述,希望对初学者有所借鉴。     

浅析高压电气设备的绝缘预防性试验

电力系统中运行着众多的电力设备,而电力设备的安全运行是保证安全可靠供电的前提。电力设备运行过程中,由于电压、热、化学、机械振动及其他因素的影响,其绝缘性能也会出现劣化,最后甚至失去绝缘性能造成事故。因此可以说电气设备绝缘预防性试验是目前保证设备安全运行的重要措施,本文主要针对高压电气设备的绝缘预防性试验进行分析论述,仅供参考。     

浅谈变压器绝缘试验的重要性

随着电力工业的飞速发展,系统电压等级逐步提高,电气设备的绝缘强度、过电压的限制水平对系统安全经济运行的影响日益突出。据统计,高压电网的各种故障多是由于高压电气设备绝缘的损坏所致,因此了解设备绝缘特性,掌握绝缘状况,不断提高电气设备绝缘水平是电力系统安全经济运行的根本保证。     

刍议变电站高压电气设备绝缘在线监测技术

随着电网容量的迅速增大,供电可靠性已显得越来越重要,因此,在线监测及诊断技术有着广阔的应用前景。本文阐述了高压电气设备绝缘在线监测技术的发展状况及其原理,并以某变电站高压电气设备绝缘在线监测系统及其存在问题进行了分析。     

浅谈变压器绝缘试验的重要性

随着电力工业的飞速发展,系统电压等级逐步提高,电气设备的绝缘强度、过电压的限制水平对系统安全经济运行的影响日益突出。据统计,高压电网的各种故障多是由于高压电气设备绝缘的损坏所致,因此了解设备绝缘特性,掌握绝缘状况,不断提高电气设备绝缘水平是电力系统安全经济运行的根本保证。     

浅析变电站高压设备在线监测系统设计

该文在简述在线监测技术发展历程的基础上,结合过往变电站高压设备在线监测系统设计中存在的主要问题,对现有试验与诊断方法进行数字化改造,拟定安设全数字一体化智能监测单元,推动变电站在线监测系统的建设进程,以实现对变电站高压设备绝缘性能多种状态参数的动态化监测。实践证明,该系统能明显提升设备缺陷检出的敏感度与有效性,加快高压设备的安全运行进程。     

Proximity Coupled Interdigitated Sensors to Detect Insulation Damage in Power System Cables

Proximity coupled interdigitated sensors are introduced to detect insulation damage in power system cables. A new empirical model for interdigitated sensors with conducting backplane is developed. The validity of this newly proposed model is verified by comparing the results obtained from the new model with simulation and experimental results. It is shown that while the existing models fail to correspond to the simulation and experimental results due to the presence of the conducting backplane, the new model can fairly approximate the effect of the backplane on the sensor performance. A meander and a quarter-circular sensor are designed for insulation damage detection. Measurement results on planar dielectric materials, as well as practical power line cables are presented to demonstrate the usefulness of these sensors. Such sensors placed on microrobots crawling along power cables could lead to the potential autonomous monitoring of an electric power system.     

超导电力装置失超检测的基础研究

超导电力装置的失超会影响超导电力设备的运行和安全，是超导电力设备技术实用化有待深入研究的一个重要问题。对国内外通用的超导装置失超检测方法进行了分析，并根据电力系统中超导装置失超检测的特点，对高温超导线材在不同幅值的动态电流作用下的失超特性进行了试验研究，通过对试验数据的分析，对高温超导线材的失超特性有了较精细的理解，并在此基础上提出了超导电力装置失超先兆检测及其失超保护设计的新概念。     

一种新型绝缘监测系统的设计

直流系统的绝缘性能直接影响直流回路的可靠性。针对监测电网直流系统的绝缘问题，提出了一种主-从式绝缘监测系统的设计方案，即用一个绝缘主模块来测量主回路的绝缘电阻，而用专门的支路模块来判断出现绝缘降低的那条支路，并利用不平衡电桥法给出了一个较为精确的，用于电网直流系统计算正负母线绝缘值都出现降低的情况下的正、负绝缘电阻的公式，在实际应用中取得了很好的效果，测量精度可达到5％。     

Digital algorithm based on orthogonal decomposition for measurement of dielectric loss factor

As one of the most important technical indexes for the evaluation of insulation condition, the dielectric loss factor is necessary in preventive experiments and online monitoring of insulation of high-voltage apparatuses in an electric power system. First, the definition of the dielectric loss factor and the impact of the harmonic voltage on that was discussed. Secondly, the voltage and the leakage current were defined as vectors in normed linear space. By using the characteristic of an orthogonal vector in the inner product space, the leakage current signal was decomposed to active and reactive components that were orthogonal. Subsequently, a novel digital algorithm of the dielectric loss factor measurement, which was defined as the ratio of norms of the active current to the reactive current, was proposed. At last, the proposed algorithm was simulated under several conditions such as harmonic voltage and voltage frequency fluctuation. In addition, the proposed algorithm was tested on two electric power capacitors. Both simulation and experiment results were provided and show that the proposed algorithm is simpler and less sensitive to influence factors than the Fourier analysis method.     

Quench developing process of HTS tape in sinusoidal overcurrents with different amplitudes

Superconducting equipments applied in electric power system might suffer overcurrents during the dynamic state of power system, such as short circuit faults. In those cases, superconducting equipments might transit from superconducting state to normal state, which is called quench, and then brings a series of problems to the supply of electric power. Thus, detecting quench timely and protecting superconducting equipments from overcurrents become an important subject. Our lab has carried out a lot of experiments to study the quench characteristics for the HTS tape in sinusoidal overcurrents with different amplitudes. By the analysis of these experimental data, this paper presents the quench developing process of HTS tape in different currents and puts out a three-stage theory for it. Based on that, the prediction theory for quench detection and protection is put forward.     

Failure analysis of transformer liquid — solid insulation system under selective environmental conditions using Weibull statistics method

The failure free operation of transformers is a main factor on economic and safety aspects as per the industrial consumer's point of view. Basically, the transformer is one of the prime equipment in power system network because of its unkind operating condition at different circumstances like higher operating temperature, overloading and continuous operation under uneven outdoor environmental conditions. Above said operating conditions lead to unpredicted failure in the transformer and this directly has an effect on reliability of the power system network. This work aims to investigate the failure rate of transformer liquid insulation (LI)–solid insulation (SI) system at various selective environmental conditions, by considering relative humidity of the air as a frequently variable environmental factor. For investigation, mineral oil (MO) and natural ester like sunflower oil (SFO) and rapeseed oil (RSO) are chosen as the LI system and Kraft paper is chosen as the SI system. The humidified samples are aged at 140 °C up to 1000 h at closed condition. Critical parameters of both LI and SI are periodically measured at an interval of 200 h. Weibull distribution statistics method is used to predict the failure rate of the insulation system with respect to time and relative humidity of the air. From the analysis, it is inferred that the degradation rate of the transformer LI–SI increases with an increase in relative humidity of the air. It is also noted that the LI-MO degrades rapidly when compared with other natural esters.     

游泳馆供冷、采暖、除湿和加热系统设计浅析

主要介绍游泳馆区域供冷、供热、除湿、泳池水保温与加热、热泵机组除霜及补充供热系统以及相应的自控系统设计,通过热泵空调热量回收供泳池加热,可减少电热水机组的开启容量,降低运行费用,节能效果十分显著.     

The Role of Interfaces in Polyethylene/Metal‐Oxide Nanocomposites for Ultrahigh‐Voltage Insulating Materials

Recent progress in the development of polyethylene/metal‐oxide nanocomposites for extruded high‐voltage direct‐current (HVDC) cables with ultrahigh electric insulation properties is presented. This is a promising technology with the potential of raising the upper voltage limit in today's underground/submarine cables, based on pristine polyethylene, to levels where the loss of energy during electric power transmission becomes low enough to ensure intercontinental electric power transmission. The development of HVDC insulating materials together with the impact of the interface between the particles and the polymer on the nanocomposites electric properties are shown. Important parameters from the atomic to the microlevel, such as interfacial chemistry, interfacial area, and degree of particle dispersion/aggregation, are discussed. This work is placed in perspective with important work by others, and suggested mechanisms for improved insulation using nanoparticles, such as increased charge trap density, adsorption of impurities/ions, and induced particle dipole moments are considered. The effects of the nanoparticles and of their interfacial structures on the mechanical properties and the implications of cavitation on the electric properties are also discussed. Although the main interest in improving the properties of insulating polymers has been on the use of nanoparticles, leading to nanodielectrics, it is pointed out here that larger microscopic hierarchical metal‐oxide particles with high surface porosity also impart good insulation properties. The impact of the type of particle and its inherent properties (purity and conductivity) on the nanocomposite dielectric and insulating properties are also discussed based on data obtained by a newly developed technique to directly observe the charge distribution on a nanometer scale in the nanocomposite.     

电力机车弓网故障的动态监测系统

目的　实时监测电力机车弓网故障 .方法　利用冲击加速度传感器以及左右限位传感器 ,实现对弓网故障的监测 .结果　设计了一套动态监测系统 ,当电力机车弓网发生故障时 ,系统能及时报警 ;同时系统还有自复位功能 .结论　司机能及时了解列车运行的情况 ,避免造成不必要的损失 .整个系统操作简单、方便灵活     

核电站电缆料的研究进展

依据核电站电缆的种类,介绍了核电站电缆料的种类、性能、生产工艺和国内外的研究现状。研究发现,制备核电站电缆绝缘料主要用交联聚乙烯(XLPE)和硅橡胶(或硅橡胶复合材料),此两种原料具有优良的耐热性、电绝缘性、耐低温性、耐化学性和良好的耐辐射性;核电站电缆料应具有低烟无卤、耐阻燃性和耐环境性能;其制备方法主要是挤出法,此方法生产工艺简单、成本低。最后展望了核电站电缆料的发展趋势。