China International Youth Conference on Electrical Engineering (CIYCEE 2020)

The main purpose of this paper is to study the saturated magnetization and demagnetization characteristics of NdFeB permanent magnets (PMs) in pulsed magnetic field, in order to provide experimental data support for the post-assembly magnetization of PM motor. For this purpose, we designed and fabricated a pulsed magnet, which had a bore of 80 mm and maximum field of 7 T. the pulsed magnet was energized by a 1 MJ capacitor bank, which can realize the switching of pulsed magnetization and AC demagnetization respectively. The residual magnetization of the PM blocks was measured by a Helmholtz coil. Finally, the experimental results indicate that the saturated magnetization field of a non-magnetized N38SH NdFeB PM block is 2.65 T. But after AC demagnetization, the saturated magnetization field increased to 3.18 T. Thermal demagnetization can bring the PM block to the initial state, and 2.55 T is enough for saturated magnetization.

Demagnetization,Magnetization,NdFeB,Permanent magnet,Pulse magnet