一起220kV电容式电压互感器事故分析

针对一起220 kV电容式电压互感器事故进行了理论分析,经现场检查与返厂解体发现,故障原因为变压器生产工艺不良导致电容式电压互感器内部发生高能放电,避免了事故的进一步发展,为今后220 kV电容式电压互感器安全运行和技术监督积累了经验。     

Optimal capacitor placement for enhancing voltage stability in distribution systems using analytical algorithm and Fuzzy-Real Coded GA

Two algorithms for optimal capacitor placement, with a view to enhance voltage stability are introduced. In the analytical algorithm the nodes, whose voltage stability index values are lower than a threshold value, are ranked in ascending order as the candidate nodes for compensation. The additional reactive power compensation to be provided at a node is obtained by solving linearized VSI formula. The maximum compensation at each node is limited to the initial reactive power delivered by the respective node prior to compensation for avoiding over-dimensioning of the capacitor banks. However, capacitor placement based on voltage stability index has proven less than satisfactory and not always indicated the appropriate placement.As an alternative a fuzzy expert system is used for extracting suitability of capacitor location from power loss reduction index and improving the voltage profile within voltage constraints. A combination of fuzzy expert system for capacitor placement and real coded GA for capacitor sizing, with a view to enhance voltage stability is proposed for optimal capacitor placement. The result is enhancement of the overall system stability index and potential achievement of maximum net money savings due to power and energy loss reduction vs. expenditure in capacitors.The overall accuracy and reliability of the proposed Fuzzy-Real Coded GA algorithm has been validated and tested on 33-node radial distribution system. Comparison of obtained results with those in recent publications showed that the Fuzzy-Real Coded GA algorithm is capable of producing high-quality solutions with good performance of convergence, and demonstrated viability.     

HVDC系统电容换相换流器特性分析(Ⅰ): 机理与特性

电容换相换流器（ＣａｐａｃｉｔｏｒＣｏｍｍｕｔａｔｅｄＣｏｎｖｅｒｔｅｒ,简称ＣＣＣ）是一种新型换流装置。本文的第Ｉ部分主要阐述了ＣＣＣ的工作机理,进行了矢量分析、波形分析以及各种运行特性分析,并对ＣＣＣ进行了综合评价,指出其广泛的应用前景。第Ｉ部分着重探究并提出了ＣＣＣ的无功功率特性、无功特性曲线以及经济补偿度等问题。     

A genetic algorithm approach in optimal capacitor selection with harmonic distortion considerations

This paper reports the research findings of an innovative genetic algorithm approach for optimizing shunt capacitor sizes and their placement in radical distribution systems with the consideration of harmonic distortion limit due to the presence of nonlinear power electronic devices. The algorithm is based on a genetic algorithm solution technique to minimize cost under the additional constraints of maximum limit in harmonic distortion factor. A harmonic distortion calculation is embedded in the genetic algorithm solution routine to enhance the optimal capacitor allocation solution. Results of simulation show that the approach is effective for such a discrete value optimization problem.     

兴城变电站电容器组继电保护装置故障分析

运行中变电站时常出现电容器组在一次设备良好 ,出现因继电保护动作使电容器组投不上的情况 ,大多是因为继电保护定值不合理或继电保护回路存在问题。本文仅对继电保护定值和继电保护设备原因引起的电容器组故障进行分析 ,以便引起有关部门的足够重视。     

765kV电容式电压互感器研制

本文主要介绍了765kV电容式电压互感器的研究和设计。对0.1级高精度、电气绝缘性能、机械强度和瞬变响应特性等关键技术问题进行了分析论证、计算和试验验证。     

产品标牌自动打印装置应用研究

为了降低CVT、并联电容器等产品标牌的制作成本,提高标牌的外观和打印的美观程度,通过市场调研,选择适合我公司标牌制作的材料,并经过对市场上的自动打印设备进行对比筛选,最终确定选用HDM-PC气动标记机来完成我公司产品标牌的制作。     

变电站电容器的运行维护与故障处理

就变电站电容器的运行电压、电路、温度、运行维护及故障处理等问题进行分析,提出应对措施,以加强电网无功系统的安全性与可靠性。     

几起35kV集合式并联电容器故障分析

集合式并联电容器已广泛用于电力系统。本文介绍了对几种电容器组运行故障原因的发现和分析 ,以及解决的方法。尤其对由于差压保护动作 ,导致投运失败的原因和处理方法作了详细的介绍。文章最后对电力系统的运行保护设定和制造厂的制造提出了建议     

重载变电站的电容器组配置

重载变电站无功缺额问题比较普遍,典型设计中所确定的尢功补偿方式不满足降损与调压的要求。因此,通过计算末端重载变电站随负倚的变化对无功的需求,分析对母线电压的影响和经济效益,提出提高补偿率、分组补偿的方法。