Calorimetric Measuring Systems: Characterizing High-Frequency Power Losses in Power Electronic Components and Systems

POWER ELECTRONICS REMAINS AN emerging technology. New materials, new devices, and new circuit topologies reduce the cost, weight, and volume for important applications [1]. Two important factors in power electronic circuits are the switching speed of the devices and the total power losses in the system. If the switching speed can be increased, improvements may be possible (e.g., current ripple in an electrical machine or physical size of passive components may be reduced). On the other hand, increased switching speed may cause additional losses in a power electronic system and increase the system cooling requirement. A common problem is that high-frequency phenomena like proximity effect, skin effect, hysteresis losses, and eddy current losses appear in the systems. These losses are very difficult to treat both theoretically and in practice. It is often difficult to measure the effect of increasing the switching frequency electrically because the system efficiency is high and a pure input-output measurement gives an unsatisfactory resolution and accuracy.