Thermoelectric Analogy Thermal Models of Power Transformers

  • W. H. Tang
  • Q. H. Wu
Part of the Power Systems book series (POWSYS)


This chapter first presents the conventional thermal models adopted in the IEC and the IEEE regulations for oil-immersed power transformers, including steady-state models, transient-state models and hot-spot temperature rise models. In order to improve the calculation accuracy of transformer thermal models, two thermoelectric analogy thermal models have been developed, which are rooted on the principles of heat exchange and electric circuit laws, including a full thermoelectric analogy model and a simplified thermoelectric analogy model. Two sets of differential equations are derived to calculate both the transient-state temperatures and the stationary-state equilibria of the main parts of a transformer. Finally, a practical means is derived to calculate hot-spot temperatures based on the outputs of the two proposed thermoelectric analogy models.


Thermal Model Power Transformer Core Loss Copper Loss Thermal Capacitance 
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Copyright information

© Springer-Verlag London Limited  2011

Authors and Affiliations

  1. 1.Department of Electrical Engineering and ElectronicsThe University of LiverpoolLiverpoolUK

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