Why does the heat dissipation of high-power power modules show significant differences? What factors should be considered when selecting a 27V DC power module heat sink for its heat dissipation effect? The editor offers a brief analysis on this issue, let's take a look at what problems contribute to these differences.
1. The length of the fin of the radiator can cause a difference in heat dissipation. During the development process, appropriately increasing the fin length of the radiator can effectively reduce the equipment temperature of the power module. However, excessively increasing the fin length does not ensure that heat is transferred to the end of the radiator fins, but rather adds too much weight to the radiator. Generally, when the fin length and base width ratio of the radiator is close to 1, the heat transfer effect is better.
2. The selection of the fin thickness of the heat sink also affects the heat dissipation function of the module. Under normal operating conditions, as heat conduction primarily occurs along the longitudinal direction of the heat sink fins on the power module, the fin thickness has little impact on the heat sink's thermal function. Adding fin thickness does not significantly reduce the temperature of the heat source, but instead increases the weight of the heat sink. To ensure the hardness and ease of processing of the heat sink fins, the fin hardness cannot be too thin. In engineering, the fin thickness of the heat sink is generally specified to be ≥1mm.
In addition to the two points mentioned earlier, the number of fins on a 27V DC power supply radiator also affects the heat dissipation function of the module power supply. Under normal operation of the module, as the number of fins increases, the junction temperature of the heat source will decrease. However, beyond a certain number, with the addition of fins, the junction temperature does not show significant changes, but the weight of the radiator increases明显. At the same time, the addition of fins may also require consideration of equipment installation issues. Some equipment is installed between the two fins of the radiator. If there are too many fins, the equipment is not easy to install on the radiator, so engineers must never blindly increase the number of fins.
