Study on structure optimization of a dual IGBT module heat sink in a DC–DC converter under natural convection based on field synergy theory

Aiming at the heat sink with dual insulated gate bipolar transistor (IGBT) modules in a direct current to direct current (DC‐DC) converter, the calculation of the temperature field of the cooling structure with low power consumption is completed by using Icepak simulation software, and analysis of the influence of the two IGBT module installation distance on the maximum temperature. The simulation results show that the maximum temperature of two heat sources decreases with the installation distance, but the maximum decline is not more than 0.5 °C. Based on field synergy theory, it is found that the local structure of the heat sink is not conducive to the natural convection heat transfer. Therefore, the improved measures of slotting the plate are proposed, and the effectiveness of this measure to reduce the heat source temperature is verified by simulation analysis and experiment. The influence of slot size on the maximum temperature of heat source is analyzed: the maximum temperature of heat source decreases with the increase of slot size. When the slot size is 16 mm, the cooling effect is obvious, and the maximum temperature drop is up to 6 °C compared with that before the slotting. Besides, the slot processing can also reduce the heat sink material and reduce the weight. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.