FDTD Analsysis of Lightning-Induced Voltages on Shielded Telecommunication Cable with Multipoint Grounding |
Jae-Cheol Ju1, Hyun-Young Lee2, Dong-Chul Park3, Nak-Sam Chung4 |
1Dept. of Electronics Eng., Chungnam Nat`l Univ 2Acess network Lab, Korea Telecom 3Dept, of Radio Science and Eng., Chungnam Nat`l Univ 4Korea Research Institute of Standards and Science |
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Abstract |
In this paper, the lightning-induced voltages on shielded twisted-pair wires with multipoint grounding on cable sheath are calculated by using finite-difference time domain (FDTD) method. The equivalent single-wire line that represents a bundle of twisted-pair wires is adopted for computational efficiency. A finitely conducting ground is also taken into account in both lightning electromagnetic field calculations and surge propagation along the shielded cable for a practical simulation. It is found that multipoint additional grounding on cable sheath provides more shielding effectiveness especially in the early time response of the lightning-induced voltages. From this study, the requirements for lighting surge protection devices in a telecommunication subscriber cab1e can be established. |
Key words:
lighting EM field, coupling, shielded cable, induced voltage, grounding |
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