A three-dimensional TLM simulation method for thermal effect in high power insulated gate bipolar transistors

Abstract

The miniaturisation of electronic networks creates problems of heat dissipation. Good thermal management is therefore essential. Simulation of power electronic systems presents peculiar challenges due to the need of detailed modelling for both circuitry and control algorithms. Transmission Line Matrix method (TLM) is a powerful tool for analysing thermal effects in electronic circuits and high power devices. In this paper, thermal analysis for a 1200 A, 3.3 kV IGBT (Insulated Gate Bipolar Transistor) module has been announced at two levels, module and system level. For the module level analysis, the thermal of the IGBT module was investigated and analysed using the Three-Dimensional Transmission Line Matrix (3D-TLM) method. The results show a three-dimensional visualisation of self-heating phenomena in the device, including the effect of the use the Metal Matrix Composite (MMC) materials as base plate over conventional materials for electronic packaging thermal control and the use of the ceramics as substrate. This paper reviews the present status of the use of various thermal heat spreader such as Al SiC MMC, Cu–Mo and Graphite–Cu MMC and comparing those with copper-based heat spreader and the use of AlN, Diamond and Beo as substrates and their effect to dissipate the heat flux in heat sources localised in IGBT module design and taking into account effects of the geometry of the module, and specific material thickness because they play an important role in dissipating the generated heat and outweigh the thermal properties of the module. For the system level analysis, the total system that consists of the IGBT module and water-cooled heat sink is analysed suited to the modelling of many power electronics devices. The thermal simulations were run for various conditions and power levels including measurement and numerical results obtained by other simulators tools as MSC.PATRAN, FLOTHERM and LAASTHERM. Results are compared. The TLM method is found to be a versatile tool which is ideally suited to the modelling of many power electronic devices and proved very useful in the study of transient thermal effects in a variety of device structures.