Investigations on the Influence of Selected Factors on Thermal Parameters of Impulse-Transformers

Krzysztof Górecki, Krzysztof Górski, Janusz Zarębski


In the paper the results of experimental investigations illustrating the influence of the selected factors on parameters of the thermal model of the transformer are presented. The form of this model and the applied method of measurements of the transformer structural components’ self and mutual transient thermal impedances are described. The influence of the selection of material of the core, its geometrical dimensions, spatial orientation, shape of the core, frequency of the primary winding current in the transformer and power lost  in this element on the considered thermal parameters of the transformer are discussed. An analytical formula describing the dependence of the considered transient thermal impedances on the internal temperature of the windings is proposed and verified experimentally.


thermal parameters, selfheating, impulse transformer

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