Research and Development Center, Westinghouse Electric Corporation, Pittsburgh, Pa.
Pages: 44 Published: Jan 1979
Much of the high-voltage inductive electrical apparatus such as transformers, reactors, motors, and generators cannot be considered as a simple lumped capacitance as is frequently done in the analysis of partial discharge circuit measurements. Particularly when the discharge occurs at a location remote from the accessible terminals for measurement of the equipment, a significant, often high, inductance occurs between the discharge site and the measurement terminals. Also, there is a distributed capacitance in parallel with this inductance, and a distributed shunt capacitance to ground. This is illustrated in Fig. 6.1. In practical apparatus, this inductive capacitance network is not usually as uniform from one end to the other, as Fig. 6.1 might indicate schematically, in an oversimplified way. This figure indicates only a sectionalized winding, and much of the apparatus is usually more complex than this. For example, no mutual inductance coupling is included in Fig. 6.1; also, no interleaving of high- and low-voltage windings or potential taps are indicated. These may introduce additional capacitance to ground at certain locations along the high-voltage winding. The inductive capacitance network of most windings, if analyzed in detail, is indeed very complex.
Paper ID: STP37826S