Measurement of Impulse Discharge Light and Image Processing for the Quantitative Analysis

由条纹相机、高灵敏度的CCD相机和微型计算机组成了图像测量与处理系统。在点对面电极上施加脉冲或交流电压，利用该系统测量了空气和SF6气体中间隙放电光的时间演化。作为对这些记录光的数字数据处理的结果，得到了光的时空亮度分布和积分亮度波，为放电光强的定量处理提供了基础研究。另一方面，为了研制气体绝缘变电站微弱放电检测系统，利用该系统对空气和SF_6气体中距绝缘子表面最近的间隙发射的放电光进行了测量，结果表明，空气和SF_6气体的正电晕亮度的延伸距离有显著差异。绝缘子表面对空气中电晕起始点和正向流光放电路径有影响，但对SF_6气体的影响较小。光谱分布的测量结果表明，空气中的间隙放电与表面放电有一定的差异，但在SF6气体中不能识别出显著的差异，测得的光强可以用亮度数来表示，但亮度数受不同的测量条件和所用仪器特性的影响。对于放电现象的定量研究，需要弄清发光亮度数与发射光子密度之间的关系。因此，采用卤素标准灯作为所用图像测量和处理系统的校准源，并推导出短间隙放电中的发射光子数。

An image measuring and processing system was constructed with a streak camera, a highly sensitive CCD camera and a micro computer. Applying impulse or AC voltage to a Point-to-plane electrodes, the temporal development of discharge light from the gap in air and SF_6 gas were measured using this system. As the results of digital data processing on these recorded light, spatiotemporal brightness distributions of the light and integrated brightness waves were derived for the basic research on the quantitative treatment of the discharge light intensity. On the other hand, emitted discharge light from a gap, which set to the nearest point from an insulator surface, in air and SF_6 gas and the spectrum distribution were measured using this system for development of detection system on the feeble discharge in the gas insulated substation.These results showed that there is remarkable differences on the extended distance of positive corona luminosity between air and SF_6 gas. The insulator surface have influence on the onset of corona and the path of positive streamer discharge in air, but the effect is rather weak in the case of SF_6 gas. The measured results on the spectrum distribution indicated that there is some difference between the gap discharge and the surface discharge in the case of air, but the remarkable difference could not recognized in the case of SF_6 gas.These measured light intensity can be expressed by the brightness number, but the number is affected by the various measuring conditions and the characteristics of used apparatus. For the quantitative study of discharge phenomena, it is needed to make clear the relationship between the brightness number and the density of emitted photons. Therefore, a halogen standard lamp were used as the calibration source for the used image measuring and processing system and the number of emitted photons in the short gap discharge were derived.