Qualitative Analysis of P_x and P_y Components of Rotational Power Loss

Four types of electrical steel are analyzed: nonoriented, conventional grain-oriented, double grain-oriented, and high-permeability grain-oriented. The results of field-metric measurement under rotational magnetization were recorded as Bx-Hxand By-Hyloops under controlled circular flux density B and circular magnetic field strength H. All the measurements were carried out at 50 Hz. A qualitative analysis of the rotational power loss is carried out by splitting the total power loss into Pxand Pycomponents and plotting as Py= f (Px) curves. These curves can take one of two distinctive forms, depending on the type of magnetization (controlled circular B or controlled circular H) and on the anisotropy of the material. The shapes of the two types of Py= f (Px) curves mostly follow piecewise straight lines. In the slanted I type, the curve exhibits two, and in the looped O type, there are four linear regions. The sharp changes in the Py= f(Px) curves are strongly linked with the shapes of B-H loops, and this technique is another tool for qualitative analysis of rotational power loss in electrical steels.