Title :
Impact of Nearby Adiabatic and Isothermal Barriers on the Thermal Characteristics of a Vertically Oriented Pot-Core Magnetic Component
Author :
Farahmand, F. ; Lavers, J.D. ; Dawson, F.P.
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Toronto, Ont.
fDate :
4/1/2007 12:00:00 AM
Abstract :
The coupled problem of estimating the temperature rise due to the winding and core loss in a vertically oriented magnetic component is considered. The principle contributions in this paper are two-fold: 1) the coupling between the losses and thermal problems for the component is addressed accounting for the effects of nearby barriers and 2) the complication that the convection coefficient is not known accurately is overcome by means of solving a coupled electrothermal-air flow problem in order to characterize heat transfer to the ambient surroundings. It is shown that the coupling between the loss and temperature in the magnetic material has negligible effects on the temperature since the deviation in temperature is not more than 13% at worst if the loss is considered constant for different barrier-to-core distances. The convection coefficients of the core´s top and side surfaces are shown not to be significantly influenced by the boundary condition imposed on the barrier. The boundary conditions substantially affect the temperature by introducing an additional path for heat transfer. Additionally, the contribution of radiation is found to be roughly 50% of the total loss regardless of the barrier height and distance and its boundary condition
Keywords :
convection; eddy current losses; electromagnetic coupling; magnetic cores; magnetic materials; switched mode power supplies; windings; adiabatic-isothermal barriers; barrier-to-core distances; boundary conditions; convection coefficient; coupled electrothermal-air flow problem; heat transfer; magnetic materials; temperature estimation; thermal characteristics; vertically-oriented pot-core magnetic components; Boundary conditions; Core loss; Couplings; Electrothermal effects; Heat transfer; Isothermal processes; Magnetic cores; Magnetic materials; Rough surfaces; Temperature; Convection; heat transfer; loss-temperature coupling; radiation;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2007.892451