Hsu Chang-Hung
Department of Mechanical Engineering, Asia Eastern University of Science and Technology, No. 58, Section 2, Sichuan Road, Banqiao District, New Taipei 220, Taiwan.
Micromachines (Basel). 2022 Nov 26;13(12):2086. doi: 10.3390/mi13122086.
This study examined micro-alternators with two different housing structures--an uncoated shell and a shell coated with an iron-based amorphous-alloy soft magnetic material. The electromagnetic power and noise characteristics of generators with these shell structures were measured and analyzed. The material used for the shell coating was the SA1 amorphous alloy. The magnetic property of the SA1 material was evaluated, including its hysteresis expansion, hysteresis-loop parameters, α-Fe crystal formation, thermogravimetric transfer, and Curie temperature. The center point of the casing was subjected to flame local-heating annealing to attain ferromagnetism and paramagnetism material characteristics. The experimental shell was between these magnetic-phase-transition properties and was used to observe the magnetic power and noise characteristics of the microgenerator. The measured magnetic flux at the center of the amorphous shell was 1.2-2.4 mT, and the magnetic flux distributed around the shell was 0.6-1.0 mT. The generator with the amorphous-alloy shell had the lowest demagnetization rate in the permanent magnet region, which was close to the bottom of the pole piece, and the magnetic flux leakage of the pole-piece side frame changed the magnetic flux path, thus affecting the demagnetization performance. For the noise experiment, the flame-annealing temperature of the local center point of the amorphous casing reached the Curie temperature, and the noise characteristics of the casing can be reduced by 15 dB compared to those of the generator without the casing. However, the overall performance of generator harmonics and power were not fully improved.
本研究考察了具有两种不同外壳结构的微型交流发电机——无涂层外壳和涂有铁基非晶合金软磁材料的外壳。测量并分析了具有这些外壳结构的发电机的电磁功率和噪声特性。用于外壳涂层的材料是SA1非晶合金。对SA1材料的磁性能进行了评估，包括其磁滞扩展、磁滞回线参数、α-Fe晶体形成、热重转移和居里温度。对外壳的中心点进行火焰局部加热退火，以获得铁磁性和顺磁性材料特性。实验外壳处于这些磁相变特性之间，用于观察微型发电机的磁功率和噪声特性。非晶外壳中心处测得的磁通量为1.2 - 2.4 mT，外壳周围分布的磁通量为0.6 - 1.0 mT。具有非晶合金外壳的发电机在永磁区域的退磁率最低，该区域靠近极靴底部，极靴侧框架的磁通量泄漏改变了磁通量路径，从而影响退磁性能。对于噪声实验，非晶外壳局部中心点的火焰退火温度达到居里温度，与无外壳的发电机相比，外壳的噪声特性可降低15 dB。然而，发电机谐波和功率的整体性能并未得到充分改善。
