Experimental evaluation of the influence of DC-premagnetization on the properties of power electronic ferrites

In many power electronic applications, ferrite cores of magnetic components are biased with a DC or low-frequency premagnetization. Usually however, the influence of the bias on the losses and permeability is not considered in the component design. This paper describes a precise measurement setup to determine the power losses and the magnetization curve of premagnetized ferrites. The measurements on typical ferrites of two major manufacturers prove that the influence of a DC-bias on the material properties cannot be neglected.