绝缘子的运行状态直接关系着特高压(UHV)电网的稳定性,绝缘子在运行过程中会出现绝缘性能下降同时伴随着表面放电,可以用紫外(UV)成像仪对其运行状态进行检测。根据直流特高压工程技术国家工程实验室(昆明)的设计要求开发了一套紫外数据管理系统,采用Delphi7作为管理系统开发软件,SQL Server2000作为后台数据库,运用模块化开发思想,建立了基本信息管理、图像处理、紫外视频播放和报表生产等功能模块,运用数学形态学提取紫外光斑中的放电参数。通过喷水分级法在现场选择了正常、良好、微孔、劣化和严重老化5种绝缘状态的同一种绝缘子,提取了"光斑直径"和"光斑面积",通过MATLAB数字仿真,得到了这2种参数随绝缘状态的变化趋势,结果表明:绝缘状态良好时,光斑面积〈250(像素点),光斑直径〈15(像素点);出现微弱放电时,光斑面积在12 000(像素点)左右,光斑直径在130(像素点)左右;当出现闪络,绝缘几乎丧失时,光斑面积〉30 000(像素点),光斑直径〉250。该软件为绝缘子运行状态的评估提供了量化依据和一定的指导。
Stability of ultra high voltage(UHV) grid is directly related to operation status of insulators.Insulation performance of insulators may degrade in operation process with surface discharge emerging,and ultraviolet(UV) camera can be used to detect the operation state of insulator effectively.Consequently,we developed a set of UV data management system on the basis of Delphi7 and SQL Server 2000.For modular development,we established a system including basic information management,image processing,UV broadcast,and statement,and utilized mathematical morphology to get the discharge parameters.Through the water spray classification method,we selected 5 kinds of insulation states such as normal,good,micro hole,degradation and serious aging,and extracted the "spot diameter" and "flare area".Through the MATLAB digital simulation,we got these two parameters changing with different insulating states.The results show that,when the insulation status is good,flare area is less than 250,flare diameter less than 15;when weak discharge appears,flare area is 12 000 or so,flare diameter is at around 130;when there is flash collaterals,insulation is almost lost,flare area is more than 30 000,and spot diameter is more than 250.This software provides a quantitative basis and certain guidance for evaluation of insulator states.