电工技术学报2024，Vol.39Issue(11)：3259-3269,11.DOI:10.19595/j.cnki.1000-6753.tces.240139
矩形波激励对纳米晶合金高频磁化过程的微观影响机理
Effect of Rectangular Wave Excitation With Different Duty ratio on Magnetization Process of Nanocrystalline Alloys
摘要
Abstract
With the increase of operating frequency,high-frequency transformers show excellent performance.Furthermore,nanocrystalline alloy,especially iron-based nanocrystalline alloy,due to its unique properties performs well as one of the core materials.In the actual working environment,the high frequency transformer is affected by the rectangular wave excitation with the change of duty ratio,which leads to the change of the material's magnetization process.the duty ratio of the rectangular wave affects the magnetization time of nanocrystalline alloy for the core material,which affects whether high frequency transformer can reach the saturation operating point.Based on the theory of the random anisotropy,a micromagnetic model of the nanocrystalline alloy at mesoscale is established,and the rectangular wave excitation with different duty ratios D is applied to the model.In addition,the magnetization ratev is defined.The influence of D on the magnetization process is analyzed from the three aspects which are the hysteresis loss Pv,the magnetization ratev and the magnetic moment deviation angular velocity ω respectively. The results show that Pv is the smallest when D=0.5,and Pv increases when D increases or decreases.When the sum of different duty ratios is 1,Pv is the same correspondingly.If the exciting magnetic field is located at the rising edge,v and ω are the smallest when D=0.1,or the largest when D=0.9.If the exciting magnetic field is at the falling edge,v and ω are the smallest when D=0.9,and the largest when D=0.1.The above results show that D can affect the magnetization time of the material.Due to magnetic relaxation,changing the magnetization time determines whether the material can achieve saturation magnetization.It proves that the difference in hysteresis loss caused by different duty ratios is caused by the rising edge and falling edge,that is,In the rectangular wave high-low level conversion,on the one hand the macro level asv,and on the other hand the micro level asω,which is caused by the difference between the two variables. In view of the fact that there exists a critical state in exploring the influence of D on the magnetization process,whichcan make nanocrystalline alloy magnetized to the saturation magnetization state exactly under the action of the external excitation source.This critical state is defined as the critical duty ratio(CDR),represented by Dc.By comparing the relationship between different duty ratios and the difference between the magnetization intensity before the transition stage and the saturation magnetization,it is found that when D＜0.5,the value of Dc1 ranges from 0.2 to 0.21.When D is less than 0.5,the value of Dc2 ranges from 0.8 to 0.81.When D＜Dc1,in the high level holding phase and can not achieve the saturation magnetization,when Dc1＜D＜Dc2,the material can reach the saturation magnetization regardless of whether it is in the high level or low level stage,when D＞Dc2,it cannot achieve the saturation magnetization in the low level holding phase.It provides reference for the selection of high frequency transformer operating points under different working conditions.关键词
纳米晶合金/微磁学/磁矩偏转/磁滞损耗/占空比/矩形波Key words
Nanocrystalline alloy/micromagnetics/magnetic domain deflection/hysteresis loss/duty ratio/rectangular wave分类
信息技术与安全科学引用本文复制引用
王怡凡,邹亮,张黎,李永建,孙秋霞..矩形波激励对纳米晶合金高频磁化过程的微观影响机理[J].电工技术学报,2024,39(11):3259-3269,11.基金项目
国家自然科学基金(51977122)和省部共建电工装备可靠性与智能化国家重点实验室课题(EERI_KF2021011)资助项目. （51977122）
