Background Introduction
Insulated Gate Bipolar Transistor (IGBT) modules are extensively utilized in energy conversion and transmission systems, particularly in electric vehicles, rail transit, ultra-high voltage power transmission, and other applications. In recent years, the power density of IGBT modules has continuously improved, leading to a significant increase in heat output per unit volume. Elevated temperatures can adversely affect the operational safety of IGBT modules, making effective thermal management increasingly critical.
Traditional active cooling technology, which relies on enhanced convection and conduction, is commonly employed in the cooling of IGBT modules due to its benefits, including efficient heat dissipation and broad adaptability. However, the increase in volume, weight, and energy consumption associated with the components of active cooling systems significantly restricts their application in integrated IGBT module cooling.
Passive cooling strategies, including phase change materials, heat pipe radiators, and radiation cooling, are lightweight, eliminate parasitic energy consumption, and provide effective solutions for the thermal management of IGBT modules. Among these, radiation cooling technology serves as a passive heat dissipation method, where heat is transferred from the heating surface to the surrounding environment through electromagnetic waves. The radiation heat flux primarily depends on the surface emissivity and temperature. High-emissivity coatings are crucial for managing thermal conditions in high-temperature environments within compact spaces. Heat pipe radiators (HPRs) represent another effective passive thermal management approach, offering advantages such as high heat transfer efficiency and robust reliability. However, HPRs are typically constructed from metal materials like copper and aluminum, which possess low intrinsic emissivity, thereby inhibiting radiation heat transfer. Consequently, integrating radiation cooling coatings with heat pipe radiators is anticipated to enhance heat dissipation performance by improving radiation heat transfer.
Recently, Li Yong and Yang Hui from the Institute of Physical and Chemical Technology at the Chinese Academy of Sciences, along with Xu Linli’s team from the Hong Kong Polytechnic University, designed a radiation-enhanced heat pipe radiator (REHPR) for the thermal management of high-power IGBT modules. The REHPR developed in this study significantly improved the heat dissipation performance of traditional heat pipe radiators through the application of a high-emissivity coating (ε = 0.93). Under a wind speed of 1 m/s and a heat load of 1500 W, the startup time and temperature rise distribution were reduced by 9% and 15.5%, respectively. Additionally, the junction temperature of the IGBT module decreased by 8.1°C and 6.8°C under heating powers of 120 W for natural convection and 1500 W for forced convection, respectively, while the thermal resistance was reduced by up to 12.5%. This study offers an effective solution to the challenge of local heat dissipation in high-power electronic devices. Future research will focus on the long-term effectiveness of the coating to promote its application across various fields. The research team plans not only to investigate the long-term stability of the coating but also to explore further optimization of the coating material composition and improvements in heat sink structure design to achieve superior heat dissipation performance and address thermal management challenges in additional areas. The findings were published in the journal *Applied Thermal Engineering* under the title “Development and Performance Study of a Radiation-Enhanced Heat Pipe Radiator for Cooling High-Power IGBT Modules.”
References:insight Thermal Management
