Calorimetric measuring systems for characterizing high frequency power losses in power electronic components and systems

High frequency power losses in power electronic components and systems are very difficult to measure. The same applies to the efficiency of high-efficiency systems and components. An important method to measure losses with high accuracy is the calorimetric measuring system. This paper describes two different calorimetric measuring systems, one for power losses up to 50 W and one for power losses up to 1500 W. These differ in size and also the systems which can be analysed. The basic concept of calorimetry is discussed and the overall performance of the two systems is specified. Methods to calibrate such systems are proposed and different applications of the systems are given. Two practical examples end the description of the research. It is concluded that such systems have a relative long time-constant but they are accurate and useful for precise power loss measurement.