Electrical-thermal analysis; modelling, and simulation of power electronics converter
Tan, Matthew Leng Fei
Date of Issue2016-05-25
School of Electrical and Electronic Engineering
This report presents a design methodology to develop electro-thermal models for High Power Density Converter (HPDC). Due to a recent trend of More Electric Engine (MEE) in the aircraft industry, small weight and volume becomes increasingly important HPDCs. In a bid to achieve a compact system with increased power density, it is inevitable that thermal issues started to surface in the system bringing about a need for effective and optimal thermal management of the system. It is important to monitor and limit the components of the power converter to its recommended temperature rating. Thus, the need and importance to develop electrical and thermal models of the said components to predict their temperature profiles and also to prevent and possible damages to the system. The design and steps undertaken to achieve these models are further elaborated into the report. By considering the critical components of the power converter, namely the power devices, inductor and capacitance of the AC filter. The power converter of interest has a power rating of 50 kW. The developed thermal model of power devices is used in the simulations. The simulation results during operation of converter under 5 litre per minute flow of water (at 700 C) in the cold plate, the mean temperature of transistors and diodes are at 1350 C and 1050 C. These are lower than recommended limit of 1500 C given in the datasheet of power module. The mean temperature of power module case is at 950 C. Additionally, the transistors recorded a peak temperature of 1400 C. These show that the cooling parameters (water temperature and flow rate) are quite optimum in cooling the transistors, with sufficient margin to the recommended temperature limit of 1500 C. An inductor was designed and constructed from scratch with its measurements verified by the LCR meter.
Final Year Project (FYP)
Nanyang Technological University