Effect of Additive Reagents in Plating Baths on Magnetic and Structural Properties of Soft Magnetic Films Prepared from Deep-Eutectic-Solvent-Based Baths
Deep eutectic solvents (DESs), a kind of ionic liquids, are expected as a novel solvent for electroplating due to their unique properties such as low vapor pressure, non-combustibility, high thermal stability, and high c ... more
The multi-domain particle model for the magnetization analysis of electrical steel sheets requires long computation time when the applied magnetic field is large. In this study, we propose a method that can efficiently m ... more
High frequency magnetic measurements for low permeability toroidal cores are demonstrated using various primary and secondary coils on low permeability magnetic toroidal cores, and effects of coils on their precision is ... more
Evaluation of Vector Magnetic Property in a Three-Phase Induction Motor Model Core with Visualization of Streamline
論文No: ページ数: 7 日付: 2023/06/01
著者: 甲斐 祐一郎(鹿児島大学),前田 怜哉(鹿児島大学),榎園 正人(ベクトル磁気特性技術研究所)
キーワード : ベクトル磁気特性,磁気損失,三相誘導電動機モデル鉄心,流線,空間的位相差 vector magnetic property,magnetic energy,three-phase induction motor model core,streamline,spatial phase difference
In this paper, a streamline display method for magnetic flux density and magnetic field strength vectors in a three-phase induction motor model core is presented, and the relationship between streamlines and magnetic pro ... more
Iron Losses Comparison of Two Kinds of Permendurs under Rotating Magnetic Flux Density Conditions
論文No: ページ数: 7 日付: 2023/06/01
著者: 祖田 直也(茨城大学 大学院 理工学研究科(工学野)),黒澤 雄司(日立Astemo(株))
キーワード : パーメンジュール,回転磁束密度条件,ベクトル磁気特性,鉄損,周波数特性 permendur,rotating magnetic flux density condition,vector magnetic property,iron loss,frequency characteristic
Vector magnetic properties of permendurs have been investigated by using a vector magnetic property measurement apparatus to select a magnetic material suitable as a motor core material. When a motor is rotated at high s ... more
This paper uses terahertz (THz) spectroscopy for the first time as a simple method for estimating the molecular weight of a polymer across a very wide range. The viscosity average molecular weight (Mv) was measured and e ... more
In 2008 the International Electrotechnical Committee (IEC) offered an ideal contact current waveform as the IEC specified waveform, while there have never been new requirements based on it for the calibration waveform. I ... more
In this paper, an accumulation of space charge in insulating materials and its effect on the discharge inception voltage were investigated by measuring the space charge distribution formed in the materials by applying a ... more
As charge injection from metal into dielectric polymer causes degradation and breakdown of electronic and power devices, the band alignment at the metal/polymer interface should be revealed. To investigate the dominant f ... more
The purpose of the study was to practice teaching electric theory to first graders using a hands-on approach in a technology teacher training course at a teacher's education university, and to verify the effect. Hands-on ... more
Experimental Study of Transmission Coil Configuration for Omnidirectional Power Transfer in Magnetic Field Coupling Type Contactless Power Transfer
論文No: ページ数: 8 日付: 2023/04/01
著者: 伊熊 哲士(千葉工業大学大学院工学研究科電気電子工学専攻),相知 政司(千葉工業大学工学部電気電子工学科)
キーワード : 磁界結合型非接触給電,全方位給電,送電コイル形状 magnetic field coupled contactless power transfer,omnidirectional power transfer,transmission coil configuration
In magnetic field coupling type contactless power transfer, there is a problem that stable power transfer is not possible to changes in the position, angle, and distance of the transmission and receiving coils. In the ca ... more
This paper presents a new plasma treatment system for decomposition of organic compounds in polluted water with high conductivity. The polluted water is normally set between two metal electrodes as a dielectric layer, bu ... more
The gas circuit breakers have the problem of re-ignition after current zero. The instantaneous voltage drop causes enormous damage in the case of current interruption failure. Therefore, it is the responsibility of circu ... more
The pulsed electroacoustic method determines the distribution of space charge in an insulation system by applying a pulse voltage and detecting the acoustic response. It estimates the location and magnitude of charges fr ... more
It is concerned that the recent expansion of the application environment of power electronics to high-altitude and/or high-radiation environments will cause deteriorations of insulation materials used in power electronic ... more
Quantitative analysis of iron loss taking magnetic hysteresis behavior into account is essential to loss reduction in electric machines. In the previous research, a novel magnetic circuit model, which incorporates a play ... more
A stress relief cone plays an essential role in a prefabricated termination for the XLPE cable system. It has been pointed out that precipitates occur on certain parts of the stress relief cone surface under long-term op ... more
Silicone gel is widely used to encapsulate power modules, and improvement of its dielectric strength has been required. So, the purpose of our research is to improve dielectric strength of silicone gel encapsulant, and w ... more
In recent years, the shift to electric vehicles (EVs) has become more prominent in many countries around the world. In line with this trend, research on systems that provide wireless power to running EVs is also underway ... more
A Novel Method Applicable to Large-Scale Active Magnetic Shielding System which Effectively Compensates Gradient Magnetic Fields Originated from the Surrounding Buildings
論文No: ページ数: 9 日付: 2023/03/01
著者: 緒方 拓斗((国研)宇宙航空研究開発機構),村田 直史((国研)宇宙航空研究開発機構),清水 隆文((国研)宇宙航空研究開発機構)
キーワード : アクティブ磁気シールド,勾配磁場,磁場補正,磁場均一度
active magnetic shielding,gradient magnetic field,magnetic field compensation,magnetic field uniformity
We propose the novel magnetic compensation method which is suitable to compensate gradient magnetic fields. The method is to be applied to a conventional large-scale, tri-axial active magnetic shielding system such as sp ... more
Effect of secondary electron emission coefficient on accumulated charge density distributions in atmospheric pressure dielectric barrier discharges have been simulated using two dimensional fluid model. Spatio-temporal d ... more
Some safety-related low-voltage cables used in nuclear power plants are required to maintain the insulation performance even during severe accidents. It is not clear whether oxygen affects the insulation performance of t ... more
Cr-doped vanadium dioxide, V1-xCrxO2 (x = 0-0.20), thin films were fabricated by metal-organic decomposition. From X-ray diffraction patterns of the films at room temperature, VO2(M2)(201) and VO2(M2)(201) diffraction pe ... more
This paper deals with partial discharge inception voltage (PDIV) and long-term voltage-time (V-t) characteristics of Polyvinyl Formal (PVF) wires in mineral oil under thermal and electrical aging. The reliability of the ... more
To further validate the IEC specified waveform as an ideal contact discharge current presented in 2008 IEC 61000-4-2, a comparison is made with air discharge waveforms from an ESD generator measured under different tempe ... more
We investigate the influence of electric field in a void of epoxy resin with fillers on development of electrical trees. Not only observations of pits and electrical trees but also measurements of temporal variations of ... more
This paper describes the deposition of Nb doped vanadium dioxide (VO2) films on a glass substrate by metal organic decomposition (MOD) and their thermochromic properties. The difference in thermochromic properties of VO2 ... more
Investigation of Quadrupole Potential Dependency on Reconnecting Magnetic Field during Tokamak Merging / Reconnection
論文No: ページ数: 2 日付: 2023/02/01
著者: 田中 遥暁(東京大学大学院工学系研究科),蔡 雲漢(東京大学大学院工学系研究科),田辺 博士(東京大学大学院工学系研究科),小野 靖(東京大学大学院工学系研究科)
キーワード : トカマク合体,ガイド磁場リコネクション,四重極状ポテンシャル,リコネクション磁場 tokamak merging,guide field reconnection,quadrupole electrostatic potential,reconnecting magnetic field
We first observed the quadrupole structure of electrostatic potential during guide field reconnection in the region of two merging spherical tokamak plasmas. The toroidally symmetric electrostatic potential is generated ... more
To study the polarization characteristics of polymer/ferroelectric composites when applied to electrical insulation in power equipment, we develop a first-principles based empirical parameter free multi-scale modeling ap ... more