论文信息 - Layer-type transformer-winding cooling factors derived from analogue solution of the governing equations

Layer-type transformer-winding cooling factors derived from analogue solution of the governing equations

The thermal problems associated with the design of layer-type h.v. transformer windings are outlined, and the concept of ‘fully developed’ thermal and hydrodynamic conditions is introduced. The equations governing the distributions of interlayer temperature and duct-oil velocity are derived for these conditions. The effect of the thermal field on oil density and viscosity in determining the velocity distribution is taken into account.The resistance-network analogue computer used in the iterative solution of the equations is described, and the procedure is explained. The results thus obtained for a particular case are compared with test values. When the test values represent significant departure from fully developed conditions, a correlation method can be employed that gives satisfactory agreement between analogue and test results within the limits of accuracy claimed. Methods for improved accuracy and further application are indicated.

P.H.G. Allen | D. J. Allan

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