A THREE-DIMENSIONAL TLM SIMULATION METHOD FOR THERMAL EFFECT IN HIGH POWER INSULATED GATE BIPOLAR TRANSISTORS

摘要

All electronic components generate heat and rejection of this heat is necessary for their optimum and reliable operation. As electronic design allows higher throughput in smaller packages, dissipating the heat load becomes a critical design factor. Simulation of power electronic systems presents peculiar challenges due to the need of detailed modelling of both circuitry and control algorithms. Numerous design techniques are implemented to achieve the optimal thermal performance but Transmission Line Matrix method (TLM) is a powerful tool for analysing thermal effect in electronic circuits and high power devices. In this paper, thermal analysis of a 1200 A, 3.3 KV IGBT (Insulated Gate Bipolar Transistor) 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 compare them with Copper based heat spreader. 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, taking into account effects of the geometry of the module, are examined. Material thickness play an important role in dissipating the generated heat and outweigh the thermal properties of the module. The TLM method is found to be a versatile tool is ideally suited to the modelling of many power electronic devices. It is especially useful in the study of transient thermal effects in a variety of device structures.