2015 IEEE Magnetics Conference (INTERMAG)最新文献

{"title":"A new general design method of segmented-rotor wound field flux-switching motors with complementary magnet circuit","authors":"R. Cao, Y. Jin, Y. Zhang, W. Huang","doi":"10.1109/INTMAG.2015.7157601","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157601","url":null,"abstract":"Permanent-magnet (PM) motors with both magnets and armature windings on stator (stator PM motors) have attracted considerable attention due to their simple structure, robust configuration, high power density, easy heat dissipation, and suitability for high-speed operations. However, they suffer from the problem of uncontrollable flux, thus limiting their constant-power operation for EVs. Also, they have the disadvantage of relatively high cost and potential resource issues because of rare-earth magnets are used. Currently, a new stator electrically wound field flux-switching (WFFS) motor with segmented-rotor and without rare-earth magnets have attracted considerable attention due to their simple and robust structure, low cost, no use of rare-earth magnet, wide speed operation range. However, the existing WFFS motors with segmented-rotor suffer from the drawbacks of asymmetry back-EMF and bigger torque ripple. The key of this paper is to propose a new general design method of WFFS motors with segmented-rotor and complementary magnet circuit.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123259420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Room temperature magnetic transition in ternary neodymium cobalt germanium 1:2:2 type intermetallics","authors":"Y. Guo","doi":"10.1109/INTMAG.2015.7157434","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157434","url":null,"abstract":"The series of rare earth (R)-3d transition metal (T)-semiconductor(S) with structural formula of RT2S2 have received much attention due to their complicate low temperature magnetic properties such as metamagnetic-antiferromagnetic, pauli paramagnetic, commensurate-incommensurate magnetic phase transition1,2. However, the magnetisms of these magnetic phenomena are not very clear. In recent years, the complicate magnetic phase states at low temperature could be understood by the skyrmion effect. A topological magnetism might be used to interpret these magnetic phenomena. In addition, the high temperature magnetic property and the magneto-transport should be an extensive study in RT2S2 system.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"134 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131059634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cogging torque optimization of a novel transverse flux permanent magnet generator with double C-hoop stator for wind power application","authors":"Z. Jia, H. Lin","doi":"10.1109/INTMAG.2015.7156611","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7156611","url":null,"abstract":"Transverse flux permanent magnet generator (TFPMG) is especially suitable for wind power application for the merits of large pole numbers, decoupled magnetic circuit, and high power density. The distinguishing feature of TFPMG is the magnetic flux existed in three-dimensional space and three-dimensional finite element method (3-D FEM) is employed to analyze its characteristics. Such as flux-switching TFPM generator [1], many TFPMGs with new topologies have been proposed. However, they commonly have a drawback that only half of PMs do work at the same time and the cogging torque vibrations are unacceptable and desiderated to be optimized. The proposed 12 pole-pairs TFPMG overcomes these shortcomings, which schematic structure is shown in Fig. 1 (a). The generator is constructed by the double C-hoop stator cores inserted into machined cavities in the stator holder, the doubled PMs screwed onto two rotor disks with opposite polarities to enable the flux-concentrated effect, and the armature winding bundling all stator hoops.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129707049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Direct growth of Bit Patterned Media — The template effect","authors":"E. Yang, Z. Liu, H. Arora, T. Wu, D. Spoddig, F. Zhu, D. Bedau, M. Grobis, B. Gurney, T. Albrecht","doi":"10.1109/INTMAG.2015.7157278","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157278","url":null,"abstract":"Template assisted direct growth of bit patterned media (TG BPM) is a novel alternative approach of producing bit patterned media (BPM). Unlike conventional BPM, TG BPM directly grows the magnetic bit patterns with oxide bit boundaries by co-depositing magnetic alloy and oxide materials onto an assisting template. In this work, TG BPM samples were deposited on different templates and the template influence on growth mechanism was studied. A functioning high density (1 TD/in2) TG BPM with excellent microstructure and magnetic properties are demonstrated.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131411548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional fluid field and thermal field research of squirrel-cage induction motors operating in broken bar fault","authors":"Y. Li, Y. Xie, Z. Wang","doi":"10.1109/INTMAG.2015.7157386","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157386","url":null,"abstract":"Taking a squirrel-cage induction motor Y802-2 as an example, 3D fluid field and thermal field of the motor operating in normal and broken bar fault conditions are researched in this paper. Considering the ventilation structure and heat transfer characteristics of the motor, the inner and outer fluid space and 3D finite element structure model of the motor operating in the healthy state, one broken bar fault and two adjacent broken bars fault state are built. The rotating fluid field and thermal field of motor operating in above three different cases were solved by using multiple reference frame (MRF) model. Then the influence of the broken bar number on the motor fluid field and thermal field is analyzed, and the accuracy of the model is validated through comparing calculation results with experimental data.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115691522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on fast calculation of dynamic process with thermal effects in electromagnetic device based on semi-analytical modeling","authors":"W. Yang, Peng Liu, G. Zhai","doi":"10.1109/INTMAG.2015.7156901","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7156901","url":null,"abstract":"Dynamic characteristics of some electrical actuators such as contactor or relay can be accurately obtained with Finite Element method though the calculation takes usually long time. However, for some high power device such calculation can be meaningless because it disregards the thermal effects of the coil. And these thermal effects can produce significant impaction to the output characters. Indeed such problems are difficult to handle because it involves coupled phenomena from various physical domains, namely thermal, electric and magnet effect. Much research has been done to deal with such multi-physics problem. Our research focuses on embedding the thermal model of the coil to the already established semi-analytical model, which can calculate the dynamic process both efficiently and accurately. As a matter of fact, the Joule heat of the coil has two main effects: altering the B-H characters of the ferromagnetic materials and altering the resistivity of the charged coil. And these changes will in turn affect the dynamic process and the heating power of the coil. The thermal transient process featured by heating power, heat radiation power and thermal resistance etc, is studied to make this coupling feasible for fast calculation based on semi-analytical model. JQ-52F, a high power DC contactor with solenoid structure, is chosen as an example to elaborate our research.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122448701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On-line demagnetization method for an iron core CT","authors":"T. Zheng, E. Hu, H. Yang, R. Zhao, Y. Kang, V. Terzija","doi":"10.1109/INTMAG.2015.7157048","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157048","url":null,"abstract":"This paper proposes a demagnetization method for iron core current transformers (CT). A dc voltage source is used to charge an inductor, and the discharging effect of the charged inductor is used to demagnetize the remanent flux of the iron core CT. To verify the performance of the proposed method, the different core characteristics, level of remanent flux, and possible errors in all elements and measured core characteristics are analyzed with EMTP-RV simulator.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122770045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Dzyaloshinskii-Moriya interaction on magnetic vortex gyration","authors":"Y. Luo, C. Zhou, Y. Wu","doi":"10.1109/INTMAG.2015.7156919","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7156919","url":null,"abstract":"This study aims to investigate the effects of Dzyaloshinskii-Moriya interaction (DMI) on vortex dynamics using micromagnetic simulation. It is found that the DMI can induce a localized bias field on the core, tilt the spin at the disk edge, and significantly affects vortex core switching. The results demonstrate that the DMI can induce the vortex core gyration with large amplitude and high stability, which may be utilized to improve the emission power of vortex based nano-oscillators.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123109029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear dynamic model of a pivot ball bearing in hard disk drive including the hertzian contact force","authors":"J. Yoon, N. Park, K. Park, Y. Park","doi":"10.1109/INTMAG.2015.7157694","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157694","url":null,"abstract":"An areal density in magnetic recording commercialization hard disk drives(HDD) is 1.2 TB/in2. It will be 1.5 TB/in2 in 2016. The head-positioning control should be more accuracy because of the high magnetic density in HDD. Previous studies of head-positioning control are considered pivot friction torque or dual actuator control system. These are not considered structural characteristic of pivot ball bearing.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114574408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimum design for improving bi-directional modulating effect of dual-permanent-magnet-excited machine","authors":"L. Jian, J. Wei","doi":"10.1109/INTMAG.2015.7157611","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157611","url":null,"abstract":"Summary form only given. Recently, dual-permanent-magnet-excited (DPME) machine has been proposed for low-speed large-torque direct drive applications [1]. Unlike traditional PM machines, the DPME machine employs two sets of PMs, one on stator and the other on rotor. It relies on the field harmonics to achieve electromechanical energy conversion, and the so-called bi-directional field modulation effect (BFME) is artfully engaged to guarantee the effective coupling between the magnetic field excited by the armature windings and those excited by the two sets of PMs. It has been demonstrated that in coaxial magnetic gears the shape factors of the ferromagnetic segments have profound impacts on the field modulation effect, and the transmitted torque density [2]. Therefore, the purpose of this paper is to investigate the optimum design method for improving the BFME of DPME machine, so as to further improve the pull-out torque of this new type of machine. Fig.1 shows the cross section view of the initial DPME machine, there are 23 rotor PMs and 27 stator PMs. Both rotor PMs and stator PMs are radially magnetized, thus each PM and its adjacent iron tooth form a pair of magnet poles. The three-phase armature windings are deployed in the 24 slots on stator, and there pole-pair number is equal to 4. The shape factors investigated are the inner width and the outer width of the rotor teeth, the inner width and the outer width of the stator teeth, and the depth of the rotor teeth, as shown in Fig.1. The depth of the stator teeth is not taken into consideration since it will affect the deployment of the armature windings. By using finite element method, the calculated impacts of these shape factors on the pull-out torque are also shown in Fig.1. Finally, the optimum design solution can be obtained by using statistical techniques such as response surface methodology. Fig.2 (a) shows the cross section view of the obtained optimum design solution, and its flux linkage distribution at no-load is shown in Fig.2(b). Comparison of the initial machine and optimum machine has been conducted. The back EMF waveforms and the pull-out torques at different current density are given in Fig.2 (c) and (d). The results demonstrated that the pull-out torque can be improved by 20 .3 % with the volume of PM used decreased by 8 .9 %.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"86 9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130997201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}