Development Of Electromagnetic Pulse Survivability Test Device For Conductive Gasket

Conductive gasket is one of the important parts in the electromagnetic pulse(EMP)protection of military electronic equipment.Because the conductive gaskets are not continuously conductive material,when they are exposed to strong EMP radiation,their resistance will increase,and even ablation may occur,thus affecting the overall shielding performance of the system.In order to ensure the shielding performance and effectiveness of conductive gaskets in EMP environment,the American military standard MIL-DTL-83528 stipulates that the EMP survivability test of conductive gaskets should be carried out,so as to select appropriate conductive gaskets in case design and ensure that the shielding performance of the whole system in EMP environment meets the requirements.At present,there is no relevant test standard and test device in China.The development of the EMP adaptive testing device of conductive gasket is helpful to the correct selection of conductive gasket,to ensure the shielding integrity of electronic equipment in the electromagnetic pulse environment,to ensure the effectiveness of weapon equipment in the electromagnetic pulse environment,and to provide the basis of preliminary research for the standardization of China’s conductive gasket testing.In this paper,the electromagnetic pulse survivability test device of conductive gaskets is mainly composed of dampened sinusoidal wave pulse current generator and conductive gaskets test fixture.The principle of the pulse current generator is to generate pulse current by RLC series circuit discharge.Because of the high voltage and high current in the circuit,threeelectrode gas spark switch is used as the main circuit switching device.By the calculation and measurement analysis,the values and types of energy storage capacitance,wave modulation resistance and pulse current detection resistance are determined,and use the vector network analyzer to measure the parasitic inductance of resistance,aimed to test and analysis the current waveform parameters in the circuit.According to the specification of the test gasket size in the standard,the test fixture of conductive gasket was designed.Then,the structural design of the test device was completed.The measured results show that the current generator can output the current with a frequency of 1MHz~1.5MHz,a attenuation time of 500ns~1300ns,and a peak-peak value of 9kA,which meets the relevant requirements in the standard MIL-DTL-83528.The electromagnetic pulse survivability of the conductive gaskets was tested by using the developed test device,and the electromagnetic pulse survivability of the conductive gaskets was analyzed and studied according to the test data.