Calorimetric concept for measurement of power losses up to 2 kW in electric drives

Abstract

Accurate measurement of power losses in high-efficiency devices is difficult. Measurement standards for industrial converters and complete electric drives, including both motors and converters, will come into effect soon, and measurement methods for these devices should be included. In the calorimetric method, the power losses are measured directly. However, the calorimeters presented previously are mainly tailored systems, and therefore, they typically have very complicated constructions. Hence, their applicability to the evaluation of general electric drives is limited. A functional calorimetric measurement concept is suggested in this study for power losses up to 2 kW. Such a power loss can be applied with present-day power electronic converters up to 110 kW. The construction of the concept is simple and lightweight. It does not require a complex structure or a large area in the measurement site. The concept is scalable and duplicable for different sizes. Different devices with different cablings can be measured without any problems. The combined standard heat loss measurement uncertainty for the calorimeter is ±0.4%.