不对称气隙对涡流限速器阻尼影响研究  

Study on Influence of Asymmetric Air Gap on Damping Performance of Eddy Current Retarder

作　　者：吴泓宇 闫贺[1] 董玉杰[1] 刁兴中[1] WU Hongyu;YAN He;DONG Yujie;DIAO Xingzhong(Institute of Nuclear and New Energy Technology,Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学核能与新能源技术研究院,先进反应堆工程与安全教育部重点实验室,北京100084

出　　处：《原子能科学技术》2023年第8期1625-1632,共8页Atomic Energy Science and Technology

基　　金：国家科技重大专项(ZX069)。

摘　　要：永磁涡流限速器是利用导体盘在永磁体形成的交变磁场中旋转产生阻尼转矩的装置,导体盘和永磁体之间的气隙是影响阻尼特性的重要因素。本文开展导体盘两侧不对称气隙对阻尼转矩的影响研究,基于等效磁路方法分析了主磁路磁通对两侧气隙不对称度δ的敏感性,基于有限元仿真对铁磁、无磁导体盘情况下的磁场分布、气隙磁感应强度、阻尼转矩和轴向力进行了对比分析,并进行了实验验证。结果表明,分别采用铁磁、无磁导体盘情况下,主磁路发生了转移。采用铁磁导体盘时,转矩和轴向力对δ显著敏感,而采用无磁导体盘时两者对δ不敏感。因此,采用无磁导体更有利于降低两侧气隙偏差敏感性。The double-sided permanent magnet eddy current retarder,equipped with a set of magnets at a certain air gap on both sides of the conductor disk to make it rotate in the alternating magnetic field to generate the damping torque,has important applications in the field of high temperature gas cooled reactor control rod drop speed limit.The double-sided magnet structure can achieve greater magnetic flux,make the structure more compact,and balance the axial forces on both sides of the conductor disk.However,due to the influence of part machining accuracy and assembly deviation,it is difficult to accurately control the air gap width on both sides of the conductor disk to be equal.And for convenience,only one side of the air gap is usually adjusted when adjusting damping in engineering applications,which increases the asymmetry of the air gap width.For different requirements such as optimal torque or maximum critical speed,the conductor disk generally selects nonmagnetic materials with high conductivity or ferromagnetic materials with high permeability.In this paper,the influence of asymmetric air gap on the damping torque was studied.First,the main magnetic path of the eddy current retarder was analyzed,the two-dimensional magnetic equivalent circuit was established,and the influence of the asymmetry degreeδof the air gap on the main magnetic flux was qualitatively analyzed.Second,based on the three-dimensional finite element simulation,the magnetic field distribution,air gap magnetic induction intensity,damping torque,and axial force in the case of ferromagnetic and nonmagnetic conductor disks were compared.Finally,the experimental verification was carried out.The results show that,for the double-sided permanent magnet eddy current device,there are two main magnetic circuits,one is very sensitive toδ,while the other is almost insensitive to it.The sensitivity of the damping torque toδcan be reduced by adjusting the magnetic resistance of the magnetic circuit to increase the proportion of the insensitive main magnet

关 键 词：永磁涡流限速器 不对称气隙 阻尼转矩 等效磁路 有限元仿真 

分 类 号：TL351.5[核科学技术—核技术及应用]