Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

A Transient Thermal Model for Power Electronics Systems

Neelakantan Padmanabhan

Abstract

An equation based reduced order model applicable to generalized heat equation and thermal simulations of power electronics systems developed in commercial CFD tools, is presented in this work. The model considers the physics of heat transfer between multiple objects in different mediums and presents a set of equations that can be applied to a wide range of heat transfer scenarios including conduction, natural and forced convection problems. A few case studies including heat transfer in a power electronic system are simulated in Ansys Icepak and the temperatures from the simulations are compared with the temperatures predicted by the models. The models are observed to be highly accurate when compared with the simulations. The predictive model described in this work reduces large complex simulations down to a few parameters which tremendously improves the computation speed, uses very low physical disk space and enables fast evaluation of thermal performance of the system for any changes in the input parameters.

A Transient Thermal Model for Power Electronics Systems

Abstract

An equation based reduced order model applicable to generalized heat equation and thermal simulations of power electronics systems developed in commercial CFD tools, is presented in this work. The model considers the physics of heat transfer between multiple objects in different mediums and presents a set of equations that can be applied to a wide range of heat transfer scenarios including conduction, natural and forced convection problems. A few case studies including heat transfer in a power electronic system are simulated in Ansys Icepak and the temperatures from the simulations are compared with the temperatures predicted by the models. The models are observed to be highly accurate when compared with the simulations. The predictive model described in this work reduces large complex simulations down to a few parameters which tremendously improves the computation speed, uses very low physical disk space and enables fast evaluation of thermal performance of the system for any changes in the input parameters.
Paper Structure (12 sections, 17 equations, 7 figures, 2 tables)

This paper contains 12 sections, 17 equations, 7 figures, 2 tables.

Table of Contents

  1. Introduction
  2. Background
  3. Models
  4. Model for 1-body insulated system
  5. Model for 2-body conduction heat transfer
  6. Model for convection heat transfer
  7. Model for multiple bodies with mixed conduction and convection heat transfer
  8. Estimation of thermal resistance and time constants for general multibody system
  9. Simulation Setup
  10. Results
  11. Model limitations and correction for steady state systems
  12. Conclusions

Figures (7)

  • Figure 1: Temperature of bodies, $T^L(t)$ from 2-body simulation and deviation terms
  • Figure 2: Analytical computation of thermal resistance
  • Figure 3: Estimated vs calculated thermal resistance
  • Figure 4: Model vs simulation for 1-body insulated system
  • Figure 5: Model vs simulation for 1-solid body (Cu-Bronze), fluid (air) medium natural and forced convection system
  • ...and 2 more figures