Optimal Programs to Reduce the Resistance of Grounding Systems

Abstract

Abstract-In this paper, some optimal programs have been proposed through the analyses of transient grounding resistance (TGR) to reduce the grounding resistance using the finite-difference time-domain method. First, the TGR of various electrode types, lengths and sectional programs is studied, and it is found that a flat bar is the most financially efficient conductor to be used as grounding electrode. Enlarging grounding electrode length can reduce grounding resistance when it is shorter than the effective length, but the reduction effect declines as the length increases. Additionally, a series of small electrodes would lead to a much lower resistance than a single large one. Second, it is demonstrated that locally improving the soil near the grounding system is an efficient way of reducing the grounding resistance. Improving a limited area soil surrounding the lifting line would reduce the peak resistance significantly, while local enlarging electrodes surrounded soil conductivity can reduce the grounding system steady resistance obviously.

Grounding Current Dispersion of HVDC Grounding System Under Dynamic Seasonal Frozen Soil

“…However, at the beginning of the construction of an HVDC system, single line transmission mode is used for a period. Double line operation mode is adopted after the completion of the HVDC system [2]. In the single line transmission mode, the grounding electrode and the earth form a loop for HVDC transmission.…”

Induced Voltage on the Overhead Line at Oil Exploiting Port Under Lightning Strike

“…The finite-difference time-domain (FDTD) method [17][18][19][20][21][22][23][24][25], which provides a simple and efficient way of solving Maxwell' equations for a variety of problems, has been widely applied in solving many types of electromagnetic problems. The FDTD method has been widely used to investigate the lightning protection since 1994 [26,27].…”