(Seminar on Earthing Systems - 21-22 May, 2008 pp. 114-129)
In this article, various methods of grounding are described with their impact on zero sequence current circulation and core damage in rotating equipment. The grounding methods for LV and MV generators are elaborated. The principles of high and low resistance grounding are discussed leading to sizing of NGT and NGR. The novel hybrid grounding concept is introduced. The dangers of mixing up incompatible grounding systems are brought out. The article ends with critical analysis of NGR enclosure earthing.
