The charge distribution on a grounding disk

Edward Kai Ning Yung, Wai Yip Tam

Research output: Journal article publicationConference articleAcademic researchpeer-review


A Fredholm integral equation of the first kind has been developed for finding the charge distribution on a circular conducting plate buried in a homogeneous earth. The method of moments is used to solve the functional equations. Techniques have been developed to evaluate and differentiate a singular integral by numerical means. An extremely fast rate of convergence has been obtained by expanding the charge distribution in functions with an appropriate singularity. It is observed that currents are dispersed into the earth in a small region near the edge of the disk. It is noted that, contrary to popular perceptions, the earthing resistance of a disk is not inversely proportional to its area. A simple empirical formula for evaluating the earthing resistance of a disk in terms of its radius, its depth of burial, and the conductivity of the earth is derived.
Original languageEnglish
Pages (from-to)872-877
Number of pages6
JournalIEEE International Symposium on Electromagnetic Compatibility
Issue numberpt 2
Publication statusPublished - 1 Dec 1989
Event1989 International Symposium on Electromagnetic Compatibility - EMC'89 - Nagoya, Japan
Duration: 8 Sep 198910 Sep 1989

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Condensed Matter Physics

Cite this