Affiliations: Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, China
Correspondence:
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Corresponding author: Xiangchao Li, Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Atmospheric Physics, Nanjing University of Information Science and Technology, 210044 Nanjing, China. E-mail: [email protected].
Abstract: Lightning overvoltage may affect the signal transmission and damage terminal equipment. In order to solve this problem, the signal system Surge Protection Devices (SPDs) is designed by analyzing the signal transmission characteristic and the design theory of SPDs. The impulse tests are performed on the SPDs using a combined wave generator. Residual voltages and sharing currents are measured and discussed by considering impulse voltages, DC breakdown voltages of downstream SPDs and decoupling resistances. The blind zone of the signal system SPDs is also discussed in detail. In addition, the SPDs are equivalent to a two-port network, and the influence of distributed capacitance of the SPDs on signal transmission is analyzed for the first time through experiments. Cut-off frequency is measured and discussed by considering DC breakdown voltages of downstream SPDs and decoupling resistances. From the two experiments, the results indicate that increasing the decoupling resistance can decrease residual voltage and sharing current, but will reduce the cut-off frequency. Decreasing the DC voltage of downstream SPDs will have a similar effect. So the decoupling resistance and the DC breakdown voltage of downstream SPDs resistance need to be considered carefully in designing signal system SPDs. The sufficient research of signal system SPDs in this paper has a certain reference value in lightning protection.
Keywords: Signal system SPDs, blind zone, sharing current, residual voltage, transmission characteristic, lightning protection
