| Vacuum circuit breaker is one of the most important protection and control equipment of the national grid, at present, it is developing to high voltage, large capacity, intelligent direction. The key technical point of this thesis is the research in vacuum arc theory and the controlling regularity. The research of vacuum arc is mainly in two aspects, the external morphological characteristics (external characteristic) and the research of plasma (internal characteristic). For the study of its external morphological, most of the scholars at home and abroad get vacuum arc image by high-speed camera and analyze arc shape through the image; For the study of the arc plasma, the existing research methods mainly contain:spectral method, probe method, dynamic thermal couple method, microwave method, laser method and so on.The main contest of this thesis is the study of the external form of arc, firstly, designing the experiment and testing system of vacuum circuit breaker arc. The experiment system is consist of main circuit, trigger circuit, the part of the vacuum generation and detection and so on. Using LC oscillation loop circuit to generate alternating current of50Hz, adopting detachable vacuum arc chamber as the experimental device, using the acquisition system which with the COMS camera as the core to get images, getting some arc images in different voltages and different gap distances.Processing arc images such as image denoising, image enhancement, edge detaction, boundary extraction, calculating arc area, arc perimeter, arc diameter and so on with the method of digital image processing to realize the essence of vacuum arc and facilitate study of the regulation on arc shape changing.In this paper, developing diagnostic system of vacuum circuit breaker arc shape which especially for vacuum circuit breaker arc image by VB and MATLAB. It can process the arc image accurately and quickly. The researchers can use it to qualitatively, quantitatively analyze arc image, compare the effects of different conditions (voltage, gap distance etc.) on the arc shape. Preparing conditions for the further study on arc control theory... |
