An Optimized Temperature Sensor Calorimetric Power Device Loss Measurement Method

In the optimized design of power converters, loss analysis of power devices is important. Compared with estimation methods, measuring the power device loss directly in the circuit under test is more accurate. The loss measurement method can be divided into two categories: electrical measurement and calorimetric measurement. The accuracy of the electrical measurement result is restricted to the accuracy of the measurement equipment and parasitic parameters, especially for fast switching devices like SiC devices. The results obtained from calorimetric measurement are more convincing. Based on the measurement principle, calorimetric measurement can be divided into four categories: flow density measurement, temperature equivalent measurement, double jacket measurement, and temperature sensor measurement. This paper proposes an optimized temperature sensor measurement method, which has shorter time consumption, a simpler setup, and lower cost. The principles of the optimized method are described and compared with the traditional ways in detail to show its advantages. The loss measurement and error analysis are carried out in a three-level ANPC (active neutral-point-clamped) topology experiment platform based on the SiC&Si hybrid module to prove the accuracy and practicability of this method.