Development of Measurement System of Magnetic Properties at High Flux Density Using Novel Single-Sheet Tester

For the design of miniature electrical machines of high power density, it is necessary to measure magnetic properties of electrical steel sheet at high magnetic flux density. The JIS standard single-sheet tester (SST) is insufficient to measure magnetic properties at high magnetic flux density around 2.0 T. In this paper, we have designed and developed an SST, which can excite high magnetic strength field up to about 58 000 A/m. The accuracy of measurement of alternating current (ac) loss at high magnetization (55 000 A/m) is verified by measuring the eddy current loss of a copper plate comparing with the theoretical value. It is shown that the magnetic properties of nonoriented electrical steel sheet can be measured until 2.1 T.