As an increasing attention towards sustainable development of energy and environment, the power electronics (PEs) are gaining more and more attraction on various energy systems. The insulated gate bipolar transistor (IGBT), as one of the PEs with numerous advantages and potentials for development of higher voltage and current ratings, has been used in a board range of applications. However, the continuing miniaturization and rapid increasing power ratings of IGBTs have remarkable high heat flux, which requires complex thermal management. In this paper, studies of the thermal management on IGBTs are generally reviewed including analyzing, comparing, and classifying the results originating from these researches. The thermal models to accurately calculate the dynamic heat dissipation are divided into analytical models, numerical models, and thermal network models, respectively. The thermal resistances of current IGBT modules are also studied. According to the current products on a number of IGBTs, we observe that the junction-to-case thermal resistance generally decreases inversely in terms of the total thermal power. In addition, the cooling solutions of IGBTs are reviewed and the performance of the various solutions are studied and compared. At last, we have proposed a quick and efficient evaluation judgment for the thermal management of the IGBTs depended on the requirements on the junction-to-case thermal resistance and equivalent heat transfer coefficient of the test samples.

Thermal Management on IGBT Power Electronic Devices and Modules

Electronics cooling research has been largely focused on high heat flux removal from computer chips in the recent years. However, the equally important field of high-power electronic devices has been experiencing a major paradigm shift from air cooling to liquid cooling over the last decade. For example, multiple 250-W insulated-gate bipolar transistors used in a power drive for a 7000-HP motor used in pumping or in locomotive traction devices would not be sufficiently cooled with air-cooling techniques. Another example is a “hockey puck” SCR of 63 mm diameter used to drive an electric motor that could dissipate over 1500 W and is difficult to cool with air because of the shape of the device. Other devices include radio-frequency generators, industrial battery chargers, printing press thermal and humidity control equipment, traction devices, mining devices, crude oil extraction equipment, magnetic resonance imaging, and railroad engines. This article classifies the cold plates into four types: formed tube...

Liquid Cooled Cold Plates for Industrial High-Power Electronic Devices—Thermal Design and Manufacturing Considerations

Recent trends including rapid increases in the power ratings and continued miniaturization of semiconductor devices have pushed the heat dissipation of power electronics well beyond the range of conventional thermal management solutions, making control of device temperature a critical issue in the thermal packaging of power electronics. Although evaporative cooling is capable of removing very high heat fluxes, two-phase cold plates have received little attention for cooling power electronics modules. In this work, device-level analytical modeling and system-level thermal simulation are used to examine and compare single-phase and two-phase cold plates for a specified inverter module, consisting of 12 pairs of silicon insulated gate bipolar transistor (IGBT) devices and diodes. For the conditions studied, an R134a-cooled, two-phase cold plate is found to substantially reduce the maximum IGBT temperature and spatial temperature variation, as well as reduce the pumping power and flow rate, in comparison to a conventional single-phase water-cooled cold plate. These results suggest that two-phase cold plates can be used to substantially improve the performance, reliability, and conversion efficiency of power electronics systems.

Two-Phase Liquid Cooling for Thermal Management of IGBT Power Electronic Module

Thermal management of power electronics is an extremely challenging problem in the harsh environment of military hybrid vehicles, where the local air and liquid coolant's temperature exceed 100 °C under regular operating conditions This paper presents the development work of a high heat flux, jet impingement-cooled heat exchanger for a 600-V/50-A silicon carbide (SiC) power module (rated at 175 °C device junction temperature), used for bidirectional power conversion between a 28-V battery and a 300-V dc bus A total of 50 volume% mixture of water–ethylene glycol (WEG) coolant at 100 °C inlet temperature is the only available coolant An array of WEG coolant microjets impinges on the base plate of the SiC module The jet impingement cooling system has been optimized by experimental studies on a surrogate module, along with a high-fidelity computational model, to accurately estimate the SiC device junction temperature in relevant operating conditions Results indicate that at the design heat load of 151 W (worst-case scenario), the SiC device junction temperature is reduced from 290 °C with commercial-off-the-shelf (COTS) cold plate cooling and 215 °C with COTS microchannel heat exchanger cooling, to 169 °C with a jet impingement-cooled heat exchanger, using the same flow rate

Liquid Jet Impingement Cooling of a Silicon Carbide Power Conversion Module for Vehicle Applications

This paper presents a comparison of conventional single-phase water/glycol liquid and innovative two-phase cooling technology for thermal management of high-power electronics automotive insulated-gate bipolar transistor modules during a full drive cycle. The proposed two-phase cooling system is built using conventional automotive air conditioning components (a condenser, an expansion valve, a compressor, and vapor and liquid lines) and a conventional cold plate as used for single-phase cooling; thus, the design does not require the development of new technology for its implementation. Three-dimensional numerical simulation in COMSOL and experimental results of two-phase cooling have been obtained on a prototype and compared to conventional water/glycol cooling high-power electronics modules, with a considerable improvement on working temperature, power transfer capacity, and equalization of die temperatures during a full driving cycle. These results suggest that two-phase cooling using the same cold plates as in single-phase cooling can be used to substantially improve the performance and reliability of electric vehicle power converters without major changes.

Comparison of the Heat Transfer Capabilities of Conventional Single- and Two-Phase Cooling Systems for an Electric Vehicle IGBT Power Module

Liquid micro-jet array impingement cooling of a power conversion module with 12 power switching devices (six insulated gate bipolar transistors and six diodes) is investigated. The 1200-V/150-A module converts dc input power to variable frequency, variable voltage three-phase ac output to drive a 50HP three-phase induction motor. The silicon devices are attached to a packaging layer [direct bonded copper (DBC)], which in turn is soldered to a metal base plate. DI water micro-jet array impinges on the base plate of the module targeted at the footprint area of the devices. Although the high heat flux cooling capability of liquid impingement is a well-established finding, the impact of its practical implementation in power systems has never been addressed. This paper presents the first one-to-one comparison of liquid micro-jet array impingement cooling (JAIC) with the traditional methods, such as air-cooling over finned heat sink or liquid flow in multi-pass cold plate. Results show that compared to the conventional cooling methods, JAIC can significantly enhance the module output power. If the output power is maintained constant, the device temperature can be reduced drastically by JAIC. Furthermore, jet impingement provides uniform cooling for multiple devices placed over a large area, thereby reducing non-uniformity of temperature among the devices. The reduction in device temperature, both its absolute value and the non-uniformity, implies multi-fold increase in module reliability. The results thus illustrate the importance of efficient thermal management technique for compact and reliable power conversion application

S. Chandrasekaran

Papers

Performance Improvement of a Power Conversion Module by Liquid Micro-Jet Impingement Cooling