• 한국농업기계학회:학술대회논문집
• /
• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
• /
• pp.528-538
• /
• 1996

A magent console is critical element since its homogeneity is essential to the performance of a nuclear magnetic resonance (NMR) based sensor. Geometry and properties of magnet materials determine the magnetic flux density and homogeneity of the console. This study is carried out to develop a design scheme of the magnet console using ANSYS to reduce the design error of the magnet console compared . To enhance the performance of the magnet console, corner steel was proposed and validated by simulation and manufactured one. The corner steel increased the magnetic flux density (B) by about 1% and enhanced homogeneity by approximately 3 times. There was about 3% difference between simulated and measured B values.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 하계학술대회 논문집 B
• /
• pp.660-662
• /
• 2002

The single phase line start permanent magnet motor has high efficiency and power factor when it operates synchronous speed. The rotor structure is composed of permanent magnet and cage bars. The motor is accelerated by rotor bars and synchronized by magnet and rotor saliency. but starting torque is disturbed by magnet braking torque so, to obtain good starting performance and synchronizing capability. the design of proper permanent magnet is required. This paper is represented performance of start ing and synchronizing by changing permanent magnet thickness

• 대한전기학회논문지
• /
• 제35권1호
• /
• pp.36-43
• /
• 1986

Superconducting magnet can be employed in many fields, such as, magnet for strong field, superconducting rotating machine and superconducting energy storage system. In this paper, the solenoid magnet design procedure and materials used in construction are described in detail, and those are the fundamentals of superconducting magnet study. The fabrication and test procedure of 3 Tesla superconduting magnet are also described. Nb-Ti is used as a superconducting wire, GFRP and Kapton are used for electrical insulation. Inner diameter of the magnet is 10 cm. According to the test results, the field at the central point of the magnet was 3 Tesla, evaporation rate per hour was 2.7 litter and current at that case was 315 A.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 하계학술대회 논문집 A
• /
• pp.253-255
• /
• 1999

In this paper, a shape optimization algorithm of superconducting magnet using finite element method is presented. Since the superconductor loses its superconductivity over the critical magnetic field and critical current density, this material property should be taken into account in the design process. Trial and error approach of repeating the change of the design variables costs much time and it sometimes does not guarantee an optimal design. This paper presents a systematic and efficient design algorithm for the superconducting magnet. We employ the sensitivity analysis based on finite element formulation. As for optimization algorithm, the inequality constraint for the superconducting state is removed by modifying the objective function and the nonlinear equality constraint of constant volume is satisfied by the gradient projection method. This design algorithm is applied to an optimal design problem of a solenoid air-cored superconducting magnet that has a design objective of the maximum energy storage.

• Journal of Electrical Engineering and Technology
• /
• 제9권6호
• /
• pp.2209-2217
• /
• 2014

A permanent-magnet-assisted switched reluctance motor (SRM) having small excitation poles, where phase coils are concentrically wound on the poles and thin permanent magnets are inserted inside the poles, is proposed in this paper. The insertion of permanent magnets into the stator excitation poles has a significant influence on positive torque improvement leading to a boost in efficiency. Three key design parameters such as the thickness of permanent magnets, space between two adjacent permanent magnets, and the width of stator excitation poles are determined during a design procedure in terms of the enhancement of positive torque. Step-by-step design modification and a comparison between the proposed permanent-magnet-assisted SRM and no-permanent-magnet SRM have been conducted by means of static torque comparison along with dynamic performance. The first prototype from steel laminations up to its physical assembly has been constructed.

• 조명전기설비학회논문지
• /
• 제28권1호
• /
• pp.29-35
• /
• 2014

The purpose of this paper is the rotor design of a single-phase LSPM(Line-start permanent magnet) motor. A single-phase LSPM motor has a permanent magnet in the rotor that is same as induction motor. For that reason, magnet is operated by breaking torque in starting region and alignment torque in driving region. Therefore, we need the design process considering the trade-off relationship. In this paper, we propose the design process of a single-phase LSPM motor for a high starting torque and efficiency with FEM. And we use Taguchi Method for considering tolerance in manufacture. Finally, we compared the LSPM motor that is designed in this paper and conventional induction motor.

• 한국초전도ㆍ저온공학회논문지
• /
• 제10권4호
• /
• pp.29-32
• /
• 2008

The design of a superconducting magnet system producing very high magnetic field is underway at Korea Basic Science Institute (KBSI) to accelerate three kinds of carbon irons (C+2, C+4, C+6) to 120 MeV. A quarter-scaled prototype will be manufactured in order to confirm the feasibility of our design. Magnet Inductances in the system have a great influence on the current ramping rates and contribute to the stored energy, which are usually considered to be unfavorable in magnet operation. The modeling and simulation scheme of a prototype superconducting magnet for the cyclotron K120 is described in this paper. The inductances are calculated by a numerical method with and without iron yokes, respectively. These calculation results will be used as engineering design details such as a current ramping rate and a quench protection design.

• 조명전기설비학회논문지
• /
• 제22권4호
• /
• pp.121-129
• /
• 2008

본 논문에서는 페라이트자석을 사용하고 있는 BLDC 전동기를 희토류 자석을 사용하는 전동기로의 설계를 다루고 있다. 최근 전기기기가 소형 경량화 됨에 따라 자석 성능이 우수한 희토류 자석을 이용한 전동기가 많이 사용되고 있다. 그러나 전기제품 메이커들은 기존의 설계를 유지하려는 경향이 있다. 본 연구에서는 전기기기에 취부되는 전동기의 외형을 그대로 하고 내부의 설계만 희토류 자석으로 변경하는 설계를 한다. 설계를 간단히 하기 위해 유한 요소법의 상용 패키지를 반복적으로 사용하였고 코깅 토오크를 줄이기 위해 고정자 요크와 고정자 단의 그루브를 설계하였다.

• Journal of Magnetics
• /
• 제16권3호
• /
• pp.312-317
• /
• 2011

NMR over 1 GHz (23.5 T) level has difficulties in design and fabrication with only low temperature superconducting (LTS) wire because of its material characteristics such as the decay of critical current under the magnetic field. Because High temperature superconducting (HTS) tape has a good performance under the extremely high magnetic field, it has been developed for high-field magnet over 23.5 T. In this paper, the LTS magnet was made for applying magnetic fields externally and the HTS coil was designed and fabricated. The electromagnetic field analysis has been done with respect to the structure and the operating current of the LTS and HTS coil. Considering to the field homogeneity and the center field, the design parameters which is suitable for the HTS coil were found. The HTS insert coil was impregnated with epoxy resin in order to prevent the movement of winding during energizing the magnet. The hybrid magnet (LTS/HTS) magnet was fabricated and tested based on the design parameters. The experimental result shows that the LTS background magnet and the HTS insert coil can be operated stable beyond 220 A and 210 A. The final value 4.32 T at the center was acquired.

• 대한전기학회논문지
• /
• 제39권8호
• /
• pp.805-812
• /
• 1990

In this paper, a design on the superconducting monolith for superconducting pulse magnet is described. Both stability and AC loss parameters are used in the design process, which restricted various design parameters. Determined design parameters satisfy both stability and AC loss restrictions. Finally superconducting monolith is flattened, fitting for magnet and acquiring transposition effect.