【作者】 刘纪英；

【导师】 王富荣；

【作者基本信息】 西南交通大学 ， 高电压与绝缘技术， 2008， 硕士

【摘要】 绝缘子是带电体与支柱设备或其它接地体保持电气绝缘的重要部件,它承受着工作电压和各种过电压,并承受着接触悬挂和支持结构的重量及因气象影响产生的机械荷载,它的性能好坏,将直接影响系统能否正常供电。因此要求绝缘子有足够的电气绝缘强度,并能承受一定的机械荷载和不利环境的影响。绝缘子经过长期使用,风吹日晒以及其它污染物,如扬尘、盐分或化工粒子等侵蚀,会导致绝缘性能下降,并产生放电现象,这种放电发展到表层空气绝缘被击穿时成为闪络,能够引起变电所跳闸而中断供电。所以有必要研究绝缘子的污秽程度,根据污秽程度的不同相应提高绝缘子的闪络电压值。本文在研究污秽闪络发生机理的基础上,根据国内外研究现状讨论了表征绝缘子污秽程度的各类特征量,确定了防污闪监测系统所需要监测的各项参数,完成了在线监测系统的详细的软硬件设计方法,利用高效低功耗嵌入式微控制器C8051F020组成了绝缘子泄漏电流在线监测系统的前台监测部分,来捕获泄漏电流的有效值、超过一定幅值的脉冲峰值和脉冲频度、温度、湿度等数据,并通过认真研究泄漏电流与环境温度、湿度和污秽程度之间的非线性关系,成功引入模糊评判模型。后台专家系统接收经MCU预处理的信息后进行模糊推理分析、判断绝缘子的污秽程度后并对前台子系统发出指令,进行实时控制。更多还原

【Abstract】 Insulators are important parts to hold the electrical insulation between pillars of equipment and other grounding, they bear a variety of voltage and over-voltage and under the hoisting of contact and support the weight of the structure because of weather and the impact of the mechanical loading, Its performance good or bad, have a direct impact on the system normal power supply. Therefore there is a request to insulator for sufficient electrical insulation strength, and can withstand the mechanical load and a negative environmental impact.After a long-term use, weathered, as well as other pollutants such as dust, salt or chemical particles, which would result in decline in insulator performance and a discharge phenomenon, the development of such a discharge to surface air insulation breakdown when a flash occur, can cause tripping interrupted in electricity substation, so it is necessary to study the contamination level of insulator, and do corresponding increase in the flashover voltage value according to the different contamination levels.Based on the mechanism study on contamination flashover, according to current research at home and abroad discussed various features that characterized the current situation insulator contamination level, identified the various parameters needed to monitor by the anti-pollution monitoring system, given the whole detail design of the hardware and software. Through serious study on the non-linear relationship between leakage current, environment of temperature, humidity and pollution level, established of fuzzy evaluation model, use the high efficient and low-power embedded microcontroller C8051F020 formed front monitor part of the insulator leakage current on-line monitoring system, to capture the leakage current RMS, the pulse peak that overtop a certain amplitude of and pulse frequency, temperature, humidity and other data. Background expert systems to receive the data pretreated by MCU and then do analysis of fuzzy reasoning, judge contamination level, give instruction to the front subsystems, realize real-time control.更多还原