Sensor Coil Influence on the Two-dimensional Magnetic Property Measurements

Abstract

Recently, two-dimensional vector magnetic measurements have become popular and many researchers have been trying to develop a more accurate measuring system and a standard measurement device. In development of high-efficiency actuators, use of high magnetic flux density designs can assist high torque, weight reduction and size down. It is therefore very important to understand the magnetic properties under high magnetic flux conditions in the electric steel sheets. However, there are still some difficulties in the measurements, due to nonlinearity and anisotropy of magnetic materials. The measured magnetic power losses of the clockwise and counter-clockwise rotating fields become different for magnetic flux density over 1.2 T and the value in counter-clockwise case sometimes became negative. It can be considered that angle errors of H and B-coils are the main reasons of the measurement errors. In this paper, the angle errors of the double B-coil (search coils) and the double H-coil (cross-type H-coil) are evaluated with a calibration device, which consists of a special solenoid coil and a high-precision turntable. The magnetic properties are compensated with the measured angle errors.