Calorimetric loss measurement system for air and water cooled power converters

The paper presents the design principles, construction and test results for a double-cased calorimeter. The calorimeter is designed to measure power losses in the range from 100 W to 2.5 kW for air and water cooled power converters. The various challenges involved in measuring losses accurately are discussed. Improvements in the calorimeter design by decoupling the heat exchanger temperature and flow control are presented and implemented in the experimental setup. Calibration results for the designed calorimeter as well as loss measurement results for a high performance three phase inverter with hybrid Si-SiC module using the calorimeter are also presented.