Research On Loss Analysis And Thermal Design Of Converter System For High Speed EMU

With the continuous raising of EMU's running speed, the heating flux of traction system is moving sharply higher. If the thermal design of electrical equipment is not paid attention to when designed, the working temperature of some components especially power switches could race up thus causes the whole system to work unstable and even failure. Besides, converter system's cooling capacity is an important factor which affects its power capacity.This paper takes EMU traction converter system as research subject and discusses its power losses and temperature distribution. A new calculation method of power losses in different circuits has been established. The average temperature of every part in converter system is calculated, and the fluctuation of IGBT junction temperature with time in one power pulse cycle is derived. Use analytical method to analyze the 2-D temperature distribution, and make a temperature distribution maps with the results. Do simulation of converter system's 3-D heat transfer condition with FloTHERM electronic simulation software. The simulation results are very intuitive, so they can help designers to find problem quickly.Thermal design of converter system is an indispensable part of power capacity design and reliability design, so it affects the structure and power disposition of EMU. This paper proposes a whole design method for traction converter system thermal design of high-speed train, and has written an application software called "Thermal design of EMU converter system software". The software provides basis for converter thermal design, while the calculation and development cost will be reduced with it.