Compact Thermal Model of the Pulse Transformer Taking into Account Nonlinearity of Heat Transfer

Abstract

This paper presents a compact nonlinear thermal model of pulse transformers. The proposed model takes into account differentiation in values of the temperatures of a ferromagnetic core and each winding. The model is formulated in the form of an electric network realising electrothermal analogy. It consists of current sources representing power dissipated in the core and in each of the windings, capacitors representing thermal capacitances and controlled current sources modelling the influence of dissipated power on the thermal resistances in the proposed model. Both self-heating phenomena in each component of the transformer and mutual thermal couplings between each pair of these components are taken into account. A description of the elaborated model is presented, and the process to estimate the model parameters is proposed. The proposed model was verified experimentally for different transformers. Good agreement between the calculated and measured waveforms of each component temperature of the tested pulse transformers was obtained. Differences between the results of measurements and calculations did not exceed 9% for transformers with a toroidal core and 13% for planar transformers.

Influence of Selected Factors on Thermal Parameters of the Components of Forced Cooling Systems of Electronic Devices

“…In this analogy, voltage represents temperature; current, power; resistance, thermal resistance; and capacitance, thermal capacitance. The formulated model is based on the idea proposed in [46,56]. According to this idea, the nonlinear Foster network is used to model the dependence of the transient thermal impedance of this device on the dissipated power.…”

Measurements and Computations of Internal Temperatures of the IGBT and the Diode Situated in the Common Case

“…To determine the value of internal temperature of each mentioned semiconductor die at the well-known power dissipated in each of them, a thermal model is used [13,16,18,29,30]. One of the forms of such a model can be a network representation.…”

“…at the well-known power dissipated in each of them, a thermal model is used [13,16,18,29,30]. One of the forms of such a model can be a network representation.…”

SPICE-Aided Compact Electrothermal Model of Impulse Transformers

“…proposed model, the non-linearity of both magnetizing core characteristic and non-linearity of the heat transfer using the thermal model proposed in [9] are taken into account, too. The correctness of the elaborated model is verified experimentally for transformers with different cores and different windings.…”

“…Due to thermal phenomena occurring in the transformer, temperatures of the core and the windings can be much higher than the ambient temperature. These phenomena contain self-heating in each transformer components and mutual thermal couplings between these components [9].…”