Study on Shielding Performance of Substation Terminal Box and Shielding Cabinet Under High-altitude Electromagnetic Pulse
Electromagnetic shielding plays an important role in the field of electromagnetic protection of electric equipment.In order to study the shielding performance of substation terminal box and shielding cabinet under the high-altitude electromagnetic pulse(HEMP)environment,the composition structure of the strong electromagnetic pulse simulator was firstly reasonably designed.Furthermore,a horizontally polarized radiation wave simulation device that meets IEC standards and can achieve early HEMP environments was independently developed.Secondly,based on the analysis results of CST electromagnetic simulation software,the shielding effectiveness of the terminal box and the shielding cabinet was calculated and compared.Finally,the strong electromagnetic environment radiation test was carried out on the terminal box and shielding cabinet using the horizontal polarization radiation wave simulation device developed.The results show that under the strong electromagnetic pulse environment,the shielding effectiveness of substation terminal box and shielding cabinet is basically below 30 dB,which means that can't achieve effective shielding.In comparison,the shielding performance of terminal box is better than that of shielding cabinet,which is consistent with the simulation analysis results,the coupling current at the end of the cable located inside the shielding cabinet and terminal box is basically not affected by the shielding effect of the shielding cabinet and terminal box.The results can provide an important reference for the protection and reinforcement of substation equipment under strong electromagnetic pulses.