• 한국초전도ㆍ저온공학회논문지
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• 제9권1호
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• pp.43-46
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• 2007

Solenoid coil is one of the commonly used one in superconducting power machines because it can produce uniform magnetic field at the center of the coil. Most of the AC loss in a solenoid coil is magnetization loss which is generated by the perpendicular magnetic field. This paper compares the electrical characteristics of two solenoid coils made of YBCO wire and BSCCO wire. We made and tested the BSCCO solenoid coil and YBCO solenoid coil which had the same number of turns and inner diameter. Number of turns and inner diameter of both coils were 30 turns and 10cm, respectively. AC loss of both coils were calculated by using the finite element method. Result shows that AC loss of YBCO coil was about 1/7 of that of the BSCCO coil when the current was 40A.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권12호
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• pp.732-738
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• 2004

In this paper, we constructed 13 turns pancake coil and solenoid coil with HTS tape and measured AC losses of the pancake coil. The critical current of the pancake coil and the solenoid coil were 80A and 109A, respectively. To compare measured AC losses of the two coils, we carried out numerical analysis using 2-D FEM program for manufactured coils. This paper presents current density distribution, flux density distribution and AC losses of the pancake coil and the solenoid. As a result, we obtained that current density distribution was closely related to the orientation of magnetic field and distribution of AC losses were also closely related to the perpendicular component of flux density distribution in coil. The calculated AC losses of the two coils showed good agreement with measured AC losses and AC losses of the pancake coil was about 9 times bigger than that of the solenoid coil under the same turns and length.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.733-734
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• 2008

본 논문에서는 Reluctance Type Coilgun의 발사체 속도향상을 목적으로, 기존의 원통형 Solenoid Coil 외에 세 가지 형태의 Solenoid Coil을 해석하여 Magnetic Field, Force, 에너지에 있어서, 각각의 분포를 분석하여 Coilgun의 성능을 향상시킬 수 있는 Solenoid Coil 형상을 설계하였다.

• Investigative Magnetic Resonance Imaging
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• 제11권1호
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• pp.20-26
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• 2007

목적 : 본 연구는 3 T MRI 장비에 적합한 동물영상용 솔레노이드 (solenoid) 코일을 개발하고 최적화한 후, 실제 동물모델에 대한 영상을 획득하는 것을 목표로 수행되었다. 대상 및 방법 : 솔레노이드 코일은 반경 4 cm, 길이 10 cm의 아크릴 구조물에 너비 2 cm, 두께 0.05 cm, 길이 10 cm의 구리테잎으로 3번 감긴 형태로 제작하였고, 구리테잎을 감을 때는 실린더 축과 수직이 되도록 감았으며 테잎간의 간격은 2 cm로 하였다. 축전지(capacitor)는 2-100 pF사이의 용량을 이용하였고, 코일은 수신 전용으로서 디자인되었다. 결과 : 개발된 솔레노이드 코일의 신호대 잡음비 (Signal to Noise Ratio; SNR)는 CuSO4수용액 팬텀(CuSO4; 0.7 g/L)에서 985, 쥐 (rat)를 이용한 동물실험에서 995이었고, Qfactor는 unload된 경우 203-206, load된 경우 84-89정도로 측정되었다. 솔레노이드 코일을 이용하여 획득한 영상은 상대적으로 해상도 (resolution)가 높았으며, 코일 시뮬레이션(simulation)을 통해서 얻은 RF field의 균질성 (homogeneity) 또한 매우 우수하였다. 결론 : 본 연구를 통하여 고자장 3T MRI 장비에서 쥐와 같은 작은 동물의 영상을 획득할 때 솔레노이드 코일을 사용하면 보다 향상된 영상의 대조도, 해상도, 선명도를 얻을 수 있는 가능성을 확인 할 수 있었다.

• 전기학회논문지
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• 제57권7호
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• pp.1175-1180
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• 2008

Recently agriculture has been intelligenced and automatized because the number of agricultural population is reduced, and the various agricultural machine is developed and utilized actively, In these agricultural automation system, the solenoid valve is widely used for the supply of water and fertilizer to the plant and soil. In this solenoid valve system, AC excitation solenoid valve is widely used because of economic merit and simple system scheme. However, the instantaneous chattering vibration and noise of plunger caused by the alternative MMF variation is very important performance characteristics. In order to reduce vibration the DC excitation solenoid valve is sometimes applied for the high-end applications. In this case, the control circuit is essential to control DC excitation current. It may causes the cost increase and system complexity and it is not suitable for the outdoor agricultural machine. In this paper, the electromagnetic structural improvement of AC solenoid valve is studied to reduce the dynamic vibration and noise. As an economical solution, the shading coil is additionally implemented to the conventional solenoid valve. As a result of this study, the vibration and acoustic noise is largely reduced by the compensating MMF of shading coil and it is verified by the test of prototype.

• 한국초전도ㆍ저온공학회논문지
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• 제5권1호
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• pp.97-101
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• 2003

When HTS tapes are used in power application, they are used by winding form, such as, a pancake and a solenoid. When AC current is applied to the coil, Ac magnetic field is generated in winding. This AC magnetic field acts as an external magnetic field and makes loss. In this paper the radial magnetic field component ($B_r$) and the axial magnetic field component ($B_z$) in a pancake and a solenoid were calculated by numerical analysis method and compare with measured value. AC losses of a short sample were calculated by Norris equation and n numerical analysis based on Brandt equation. AC losses of the pancake coil and the solenoid coil were also calculated.

• 한국기계가공학회지
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• 제17권2호
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• pp.118-123
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• 2018

Coil guns are known worldwide as inexpensive space launch vehicles. The principle of Fleming's right-hand rule allows the coil gun to accelerate the projectile by applying enormous voltage to the solenoid coil. This study was performed to improve the speed of the coil gun using MATLAB, a commercially available numerical program for high launching force of electromagnetic projectiles. To maximize the speed of the projectile, the largest coil of American wire gauge was used, and the number of windings in the radial and axial directions of the solenoid coil was optimized. Optimal length of the projectile was obtained by calculating the optimal aspect ratio between the axial length of the solenoid coil and the length of the projectile.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권2호
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• pp.239-245
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• 2013

Modern electric controlled valves are demanded that its solenoid actuator should be smaller size, lighter weight, lower consumption power, and higher response time. For achieving these purposes, the major design factors of solenoid actuator such as magnetic flux density, coil turn numbers, plunger size, bobbin dimension, and etc. are must be optimized. In this study, for optimal design of high speed solenoid actuator for hydraulic servo valve operation, we draw up governing equations which are composed by combination of electromagnetic theories and empirical knowledge, and deduct the values of major design factors by use of them. For more increase the operating speed, voice coil are used as main armature in manufacturing of prototype actuator. And, we have proven the propriety of the governing equations and speed increasing method by experiments using the hydraulic valve assembly adopted the prototype of solenoid actuator.

• 한국자기학회지
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• 제25권3호
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• pp.87-91
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• 2015

본 논문에서는 코일건 발사 시스템의 성능 향상을 위한 솔레노이드 설계에 대해 연구하였다. 즉, 코일건 솔레노이드의 코일 직경에 따른 피투사체의 발사속도에 대한 분석을 수행하였다. 코일건은 자기력을 이용하여 피투사체를 발사시키는 시스템이다. 솔레노이드에 순간적으로 큰 전류를 흘려주면 코일 주위에 순간적인 자기장이 만들어지고, 발사체는 플레밍의 오른손 법칙에 따라 코일의 중심 방향으로 자기력을 받아 발사된다. 피투사체의 발사 속도는 솔레노이드 코일이 생성하는 자기력과 비례한다. 하지만, 솔레노이드 코일은 규격에 따른 최대허용 전류가 존재한다. 따라서, 한계 전류 내에서 피투사체에 작용하는 자기력이 최대가 되는 솔레노이드 코일의 설계가 필요하다. 본 논문에서는 솔레노이드 코일의 설계를 위해 AWG(American Wire Gauge)6부터 AWG18까지의 코일의 직경에 따른 최적의 권수를 찾아서 발사가능여부와 그에 따른 발사속도를 비교 분석한다.

• 자연과학논문집
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• 제8권1호
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• pp.27-32
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• 1995

역-솔레노이드 코일 형태를 이용한 핵자기공명용 내부영상 탐침을 제작하였다. 역-솔레노이드 탐침들로 획득된 영상의 신호-대-잡음비를 시제품 탐침인 머리코일과 몸통코일로 얻은 것들과 비교하였다. 내부영상에 관한한, 본 논문에서 제작된 역-솔레이노이드 탐침들이 위의 시제품 탐침들보다 향상된 기능성을 보였다. 그리고, 역-솔레노이드 탐침들이 형성하는 RF-자기장의 분포를 컴퓨터를 이용하여 계산하였다. 아울러, 본 논문에서 제작된 역-솔레노이드 탐침을 이용한 인체의 내부영상의 가능성에 대해서도 논의하였다.