A Fourier Series-Based Steady-State Thermal Resistance Model for Power Module

The finite-element method (FEM) is conventionally employed to evaluate the thermal performance of power modules (TPPM), but it demands substantial computational resources and time. This study introduces a novel approach for TPPM assessment through a Fourier series-based steady-state thermal resistance model (FSS-TRM), which offers enhanced computational efficiency and accuracy. The FSS-TRM integrates conduction and spreading resistance via a mathematical-physical method, explicitly focusing on redefining conduction resistance to optimize computational efficiency. The accuracy of the FSS-TRM is ensured by solving the heat conduction differential equation to obtain spreading resistance. To assess the reliability of the FSS-TRM, the model is tested across varying direct bonded copper (DBC) configurations and chip sizes. Experimental results reveal that the maximum error of the FSS-TRM compared with the conventional COMSOL approach is below 4%. In addition, the FSS-TRM's capability to predict TPPM is verified through testing a representative power module in a 34-mm package, demonstrating an error of only 0.9% compared with both COMSOL and experimental results. Notably, the computational efficiency of the FSS-TRM is significantly improved, exceling COMSOL by five orders of magnitude. Therefore, the proposed FSS-TRM provides an accurate and efficient alternative to FEM for TPPM estimation.

IEEE Journal of Emerging and Selected Topics in Power Electronics

IEEE Journal of Emerging and Selected Topics in Power Electronics

12

2168-6785

N/A

4

13