Vacuum Interrupter Insulation Level Of Analysis And Discussion

Because of its huge advantages,vacuum switches have been widely used in the middle voltage domain of power transformer electrical network. And with the continuous development of power systems, and the continuous improvement of system capacity, vacumm switches are developing toward the orientation of large capacity, compactness, high reliability and high degree insulation. However, as the heart of the vacuum switch components, the insulation level of vacuum interrupters far failed to meet the needs of development for vacuum switches, so, the application of vacuum switches on higher voltage area is limitsed. Coupled with the reliability problems in the application so that the insulation level of vacuum interrupters becomes the key issue. To solve this problem, the advantages of strong breaking abilities of vacuum switches can be fulfilled, and the application domains in the power system can be occupated.In this article, on the theory of insulation mechanism of vacuum interrupters,and with being the object to research that product on 10kV model, the internal electric field is simulated and analysised, internal structure is improved, a new type of contactor material is selected, the once seal-exhaust technique is adopted. And with comparison of test data, each factor that influence the insulation level of vacuum interrupters is verificate. And with the carrying out of this topic, the quality rate of the product is raised, and the experience for the optimal design and exploit of new products of vacuum interrupters in vacuum switches is gathered.In chapter 1, the background and inducement of this article is introduced, the research situation on the insulation level of vacuum interrupters in our country and abroad is explained, the research goal and direction of this article is concluded, and the outline of the thesis is planned.In chapter 2, the basic structure and the principle of work of vacuum interrupters is mentioned above all, then a varirty of factors to influence the insulation level of vacuum interrupters are introduced emphatically. Finally, the failure mechanism to vacuum insulation is represented.In chapter 3, according to the factors that influence the insulation level of vacuum interrupters, the breakdown characteristic of a interrupter is analysised again, the internal electric field is simulated and analysised, the design proposal of the insulated enclosure is concluded. And with the use of the new material of contactor and bellows and adopting the once seal-exhaust technique, the interrupte is improved.In chapter 4, emphatically through the tests of working frequency insulation and raiden impact insulation, the effect of improving with the product is verificated.In chapter 5, the thesis is summed up and some possible research directions in the future is concluded.