【作者】 胡磊；

【导师】 叶佳卓； 陈希华；

【作者基本信息】 湖南大学 ， 电气工程， 2017， 硕士

【摘要】 电力变压器是最常用的配电设备。电力变压器经常超负荷运行会因绝缘损坏造成安全隐患,电力变压器油色谱在线监测系统通过对油中溶解气体成分及含量的分析,可实时监控运行中变压器工作状态。这样做不仅有利于变电站的自动化,减少巡视和维护,更能通过实时监控,预防和减少变压器故障。本文主要做了以下工作:(1)阐述了电力变压器油中溶解气体在线监测的研究背景及意义和国内外的研究现状,总结常见的电力变压器故障类型与变压器油中溶解气体含量的关系。将电力变压器油中溶解气体在线监测与故障类型诊断相结合,分析了二者的关系,并提出了一种专家诊断算法。(2)解释了气相色谱分析的相关概念。阐述了一些常见气体传感器的工作原理与优缺点。完成了色谱仪器硬件电路和气路的设计,指出了部分硬件的元器件选择,最后将所有模块集成在同一块板子上。最后,设计了色谱仪器的软件,实现程序的控制电机旋转与电磁阀门动作,控制温度,与上位机通信,色谱数据采集与分析,色谱仪程序与上位机程序的通信,上位机与色谱仪的数据传输。(3)设计了在线监测系统的上位机软件,可在线监测电力变压器油中气体组分和浓度。能在计算机上动态显示色谱图,历史数据可自动保存供以后查阅。上位机软件具有谱图管理,谱图采集与显示,谱图处理,定性及定量,结果输出,自动化,帮助等功能。上位机软件还有RS485通信功能。色谱仪器的硬件主要负责数据采集,数据采集的关键是模数转换芯片的位数,位数越高转换精度越高。ADS1246具有很高的采样速度和精度。更多还原

【Abstract】 Power transformer is the most commonly used distribution equipment.Power transformer runs over load frequently will cause insulation damage and security risks,power transformer online monitoring system based on the composition and concentration analysis of dissolved gas in oil,can real-time monitor the working status of running transformer.It not only is helpful to substation automation,reduce patrol and maintenance,but also can prevent and reduce transformer failure through real-time monitoring.This paper has done the following work:(1)Describes the background and significance and domestic and international research status about the gas dissolved in power transformer oil online monitoring system,summed up the relationship between power transformer common fault type and the concentration of dissolved gas in power transformer oil.Combining the gas dissolved in power transformer oil online monitoring system with the fault type diagnosis,It has analyzed the relationship between the two subjects,and proposed an expert diagnosis algorithm.(2)Explained the concepts related to the gas chromatography.Explained the working principle,advantages and disadvantages of some common gas sensors.The design of the hardware circuit and gas circuit of the chromatographic instrument is completed.The selection of some hardware components is pointed out.Finally,all the modules are integrated on the same board.Finally,the chromatographic instrument software is designed.It has realized the program control of motor rotation and electromagnetic valve action,temperature control,and PC communication.It has realized chromatographic data acquisition and analysis,communication between chromatographic instrument program and PC program,data transmission between PC and chromatographic instrument.(3)The PC software of online monitoring system is designed,it can online monitor the gas composition and concentration of power transformer oil.The dynamic chromatogram can be displayed on the computer,and the historical data can be automatically saved for future reference.The PC software has the functions of chromatograms management,chromatograms collection and display,chromatograms processing,making sure quality and quantity,result output,automation,help and so on.The PC software also has the RS485 communication function.The hardware of the chromatographic instrument is mainly responsible for data acquisition,and the key to data acquisition is the number of bits of analog to digital conversion.The higher the number of bits,the higher the conversion accuracy.The sampling speed and accuracy of ADS 1246 is very high.更多还原