AN IMPROVED WAVEGUIDE MODEL TO SUPPORT ANALYSIS OF ELECTROMAGNETIC SHIELDING FOR LIQUID COOLED POWER ELECTRONICS

This paper describes ongoing work to develop and validate an improved waveguide model in order to support analysis of shielding effectiveness at frequencies from 8 GHz to 25 GHz. Waveguides may be used in the coolant loop for liquid-cooled, high-voltage power electronics to maintain the shielding effectiveness of the enclosure surrounding the power electronics. Different formulas for shielding effectiveness are reviewed and their applicability and limitations examined. The improved model is then used to predict the shielding effectiveness of an air-filled waveguide with a hexagonal or “honeycomb” insert installed. The results obtained are then compared with results obtained by modeling and simulation using FEKO.