Studies On Model And Experiments Of Gas Spark Switch Electrode Erosion

Gas spark switch is a basic device commonly used in pulse power driving source.It has the advantages of high power level,low cost and easy maintenance.It has important applications in defense technology and high-tech fields such as high-power microwave,flash photography and Z pinch.As the core device of the pulse drive source,the switch often has a decisive influence on system performance.Electrode erosion during the discharge of the switch is one of the key issues that have long troubled the development of switch technology.The change of the electrode surface state caused by the electrode erosion affects the switch self-breakdown voltage,which can lead to unexpected switch self-discharge;the erosion metal vapor pollutes the switch internal environment,resulting in deterioration of the insulation voltage tolerance performance and even insulation failure.At present,there have been many studies on the switch erosion mechanism and experimental law,but it is still not perfect,especially for the discharge of tens of thousands of amperes,the model's qualitative analysis of the switch mass loss,the erosion parameter change rule under a specific discharge It is not deep enough.Therefore,it is of practical significance to analyze the electrode erosion mechanism and the experimental change of erosion parameters under a specific current,which is also the main research content of this article.The main research contents and results of the paper are as follows:1.The research status of gas spark electrode erosion at home and abroad is introduced,and the research viewpoint of this paper is put forward in view of the shortcomings in the research.The switch discharge theory,discharge basic parameters and discharge current density distribution are analyzed,which provides theoretical basis for the establishment and analysis of ablation model.2.The one-dimensional electrode erosion model is established by using the heat conduction equation,in which the latent heat of phase change is used as the main internal heat source.The current density distribution of and the different heat flux sizes of the cathode and anode are considered in the model,which can be used to calculate the vaporization mass loss of the material.The results show that the degree of erosion of stainless steel and brass is basically the same.The stainless steel electrode is more resistant to erosion than the brass electrode.The calculated erosion quality change is basically equivalent to the experiment,which can be used as a preliminary prediction of the switch quality loss.3.A switch test platform is setup;the electrode erosion parameters is measured and analyzed;the electrode erosion characteristics under different current discharges of short-circuit discharge and damped discharge are studied;the erosion experiments of stainless steel(1Cr18Ni9Ti)?brass(H62)?graphite(EDM-AF5)and tungsten copper alloy(W-10Cu)electrode are carried out,the impact of material properties on erosion is analyzed,and the calculation model is compared and verified.The research results show that: the discharge current peak and period increase,the electrode material erosion rate increases,and the electrode surface roughness increases;graphite is an electrode material superior to metals.In metal electrode,the tungsten-copper alloy has a small quality loss and the performance is better than brass and stainless steel;damping and short-circuit discharge,the calculated mass loss of the cathode and anode is close to the experiment and the same trend as the experiment,the cathode mass loss is less than the experimental result,the anode mass loss calculated under the short circuit is greater than experiment.