Research On Morphological Characteristics Of The Vacuum Switch Arc Within Short-gap And Large Current

The safe operation of power grid needs the protection of the vacuum switch. The function of vacuum switch is to cut current timely when the power grid fails. Since the vacuum switching arc affects the cut-off performance of vacuum switch directly, so we make the short gap vacuum switch as the research object. In this paper, the arc image is disposed combined with digital image processing technology, the quantification of the geometric characteristic parameters and macro particle velocity in the burning process of short gap vacuum switch are achieved. Thus we lay a good foundation for the quantitative analysis of short gap vacuum switch.In order to study the short gap vacuum switching arc shape, in this paper, the short gap vacuum switching arc image acquisition system is introduced, and the image of whole burning process of short gap(7mm) vacuum switching arc.In order to highlight the characteristics of arc image, the feature of short gap vacuum switching image (1.3ms) is extracted with digital image processing technology. First of all, digital image processing software MATLAB7.0is simple introduced. Then we do noise processing, enhancement process, edge detection process, thresholding, boundary extraction processing, two-dimensional wavelet decomposition and reconstruction on the arc image. At last the processed arc image is analyzed and compared.In order to achieve the quantitative description of short gap (7mm) vacuum switching arc shape, we do thresholding and boundary extraction processing on arc image in the whole burning process combined with digital image processing technique. The geometrical characteristic of arc is extracted, and the area and perimeter values are calculated combined with arc geometric feature parameter calculation arithmetic. The changing and growth curves of arc area and perimeter are drawn. Through the quantitative description of arc geometrical characteristic, the whole burning process of short gap vacuum switch arc is analyzed combined with the internal stress distribution in the burning process of arc.