图像灰度标准差对介质阻挡丝状放电分布均匀性的定量评价  

Evaluation of the Distribution Uniformity of Filamentary Dielectric Barrier Discharge by Standard Deviation of Image Gray Levels

作　　者：于大海[1] 叶齐政[1] 杨芾藜 谭丹[1] 

机构地区：[1]强电磁工程与新技术国家重点实验室(华中科技大学),湖北省武汉市430074 [2]重庆电力科学研究院,重庆市渝北区401123

出　　处：《中国电机工程学报》2013年第28期193-200,28,共8页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51177059)~~

摘　　要：由长时间尺度大量丝状放电组成的介质阻挡放电的分布均匀性评价目前并无合适的方法,前期研究曾提出利用图像灰度标准差(standard deviation,Std)识别分布均匀放电和丝状放电,但对于采用灰度Std定量评价这种放电分布均匀性还缺乏分析。通过提出多个微放电灰度叠加模型,计算了多个微放电不同叠加形式的灰度Std,探讨了采用灰度Std评价丝状放电分布均匀性的可行性。计算结果显示:在微放电个数较少时,灰度Std虽小,但放电不均匀;当微放电个数超过一定值时,灰度Std越小,放电越均匀。这表明灰度Std在微放电足够多时可以反应放电分布均匀性。实验结果与计算结果吻合。因此,在曝光时间等拍摄条件一致时,灰度Std可以定量评价不同工况下丝状放电分布均匀性。Currently there is no effective method to evaluate the distribution uniformity of barrier discharge consisted of numerous filaments within a long time duration, and a previous research classified the uniform and filamentary discharge by the standard deviation （Std） of gray levels, while using the Std of gray levels to quantitative evaluate the distribution uniformity of filamentary discharge needs further analysis. A multiple microdischarge superposition model is proposed, and the effect of multiple microdischarges superimpositions on the distribtution uniformity and Std of gray levels is investigated. The calculation results show that even the Std of gray levels is small, while the discharge is non-uniform in the case of a small number of microdischarges. When the number of microdischarge is large enough, the smaller the Std of gray levels, the more uniform the discharge. This suggests the Std of gray levels could reflect the gray dispersion from the mean of gray levels. The experimental results identified the calculation results. And moreover if the shooting conditions maintain consistent, the Std of gray levels is a good indicator of the distribtution uniformity of filamentary discharge in a long time scale.

关 键 词：介质阻挡放电 丝状放电 分布均匀性 灰度 标准差 高斯分布函数 

分 类 号：TM85[电气工程—高电压与绝缘技术]