Design of a Novel Test Fixture to Measure Rotational Core Losses in Machine Laminations

The need for testing magnetic materials used in electric machine laminations and measurements under a rotating field is of importance in machine design. In order to obtain satisfactory experimental data, the design of the measurement apparatus deserves particular attention. The purpose of this paper is to propose a novel design of a magnetic circuit based on the Halbach array, which generates a uniform flux density inside the test specimen for the measurement of rotational core loss. The proposed design is simulated and prototyped, and experimental tests are performed on two different samples of M19 gauge-24 and M36 gauge-29 silicon steel at three different frequencies (60 Hz, 400 Hz, and 1 kHz). The field-metric method is used in this work to evaluate the rotational core losses.

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