电磁轨道发射装置绝缘体绝缘性能的实验研究

Experimental study on insulation performance of insulator in electromagnetic rail launcher

电磁轨道发射装置绝缘体在发射试验后易出现绝缘性能劣化而影响发射装置寿命。为研究不同劣化因素对绝缘性能的影响规律,将影响绝缘性能的因素解耦成6个独立状态,并对这6种典型的绝缘劣化形貌的形成和危害进行了讨论,设计了绝缘性能实验。不同试样的表面电阻率测量结果表明:积铝和液膜对绝缘劣化的影响最大,杂质和接缝处积铝其次,烧蚀碳化和膛内高温的影响最小;不同试样的直流沿面闪络电压高于交流沿面闪络电压,但二者变化趋势相似,均可以反映材料的绝缘性能;试样的耐受电压能力与其表面电阻率关系密切,积铝和液膜导通了试样表面,杂质和接缝处积铝试样的耐受电压能力较差,约为烧蚀碳化试样的1/2、加热试样的1/4。

The insulation performance of insulator in electromagnetic rail launcher is easy to deteriorate after launch tests,which affects the life of the launcher.In order to study the influence of diffe-rent deterioration factors on insulation performance,the factors affecting insulation performance were decoupled into six independent states,the formation and harm of these six typical insulation deterioration morphologies were discussed,and insulation performance experiments were designed.The surface resistivity measurement results of different samples show that aluminum deposition and liquid film have the greatest impact on insulation deterioration,followed by impurities and aluminum deposition at joints,and ablation carbonization and high temperature in bore have the least impact.The DC flashover voltage of different samples is higher than the AC surface flashover voltage,but their change trends are similar,which can reflect the insulation performance of the materials.The withstand voltage capability of the samples is closely related to their surface resistivity.Aluminum deposition and liquid film conduct the surface of the samples.The withstand voltage capability of the samples with impurities and aluminum deposition at the joints is poor,which is about 1/2 of the ablated carbonized sample and 1/4 of the heated sample.