Comparative Evaluation of Electrical and Calorimetric Methods to Estimate Core Loss in Powder Cores

Abstract

The utilization of powder cores for many power electronic applications has drawn a significant amount of attention owing to their attractive magnetic properties. However, because of their low relative permeability characteristics, a precise measurement of the core loss is very difficult to obtain. Imprecise estimation of the core loss may lead to an inaccurate thermal design of power converters. Measuring and calculating the accurate value of the core loss allows the circuit designer to design a more efficient system. This paper discusses the revalidation of electrical measurement by comparing the electrical method with the calorimetric method in powder cores. The calorimetric method is one of the most promising methods to accurately measure the core loss; however, it is time consuming. A difference less than 10% has been reported for the core loss measurement error while comparing the electrical method and the calorimetric method in various conditions. These results indicate that the electrical method using the B-H analyzer is effective for measuring the core losses in some conditions for powder cores. Along with the theoretical discussion, simulation and experimental tests are also conducted.

Conceptual Diagrams of Extended Building Factor for Analysis and Evaluation of Factors on Core Loss Density Increase in IPMSM

“…4 and 6 of the past study (29) , when the peak magnetic flux density is Bm = 1 T and the carrier frequency is fC = 10 kHz, the measured results of the iron loss of a ring sample with the two measurement methods agree well. Besides, according to another previous work (30) , the obtained results of the iron loss with the two methods have an average difference of around 5%. We also can see that the PDM presented in (23) has a similar principle to the technique shown in (9) for measuring the IPMSM core loss as used in this paper.…”

“…According to the past studies (29) (30) , there are two measurement methods often used for determining the iron loss of a ring sample. The first one is based on the measured H and B such as expressed in ( 4)-( 6) used in this paper, while the other is based on subtracting the losses (such as the copper loss) other than the iron loss ܹ ୣ,୰୧୬ in the ring sample from the input electrical power consumed by the ring sample as shown in (23).…”