• 한국전자파학회논문지
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• 제7권4호
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• pp.346-352
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• 1996

초광대역 주파수 특성을 가지며, 제2층에 십자형 슬롯을 가지는 2층형 전파흡수체의 광대역 설계법을 제안하였다 이와같은 광대역 전파흡수체는 등가재료정수법을 적용한 이론 모델을 이용하여 설계할 수 있다. 제안한 모델을 바탕으로 30MHz~3,170MHz의 주파수 범위에서 우수한 반사감쇠 특성을 가지는 초광대역 전파흡수체를 설계하였다.

• 한국소음진동공학회논문집
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• 제21권5호
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• pp.475-483
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• 2011

A hybrid electromagnetic actuator with an air mount is designed so as to achieve the desired isolation reduce the vibration efficiency on the floor vibration. The performance specification of the hybrid electromagnetic actuator is determined based on the vibration criterion for vibration-sensitive equipment. In the design stage of the electromagnetic actuator, the simple reluctance method is adapted to analyze magnetic circuits. The result is verified by finite element analysis using ANSYS Emag. Finally, in order to confirm the design performance, a dynamic characteristic test is carried out for the prototype of a hybrid electromagnetic actuator.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2000년도 종합학술발표회 논문집 Vol.10 No.1
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• pp.272-276
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• 2000

본 논문에서는 I/O Cable을 가지는 일반 통신시스템의 전자파 방사 Mechanism을 분석하고, Design에 있어 중요한 Parameter를 도출하였다. 중요한 Design Parameter로 도출된 I/0 Cable의 Coupling mechanism을 실험 및 상용 Software를 이용한 Simulation방법에 의해 분석하고, 이에 대한 EMC Design Rule을 제시하였다. 도출된 EMC Design Rule을 준수하여 Design을 실현하고, 그 효과를 분석하였다. EMC Design Rule에 기반을 둔 개발을 통해 제품의 Redesign및 복잡한 Debug 과정이 없이 효과적으로 전자파 양립성 규격을 만족하였다.

• Journal of Magnetics
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• 제16권4호
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• pp.374-378
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• 2011

Axial Field Permanent Magnet (AFPM) generators are widely applied for the small wind turbine because of the higher power density per unit weight than that of the conventional radial field generator. It is caused by the disc shaped rotor and the stator structures. The generally used AFPM generator, AFER-NS generator, is composed of the two side's external rotors and non-slotted stator without stator core. However, the output voltage and the output power are limited by the large reluctance by the long air-gap flux paths. In this paper, the design study of AFIR-S generator having double side's slotted stator core is accomplished to improve the output generation characteristics. The electromagnetic design analysis and the design improvement of the suggested AFIR-S generator are studied. Firstly, the electromagnetic design analysis was done to increase the power density. Secondly, the design optimizations of the rotor pole-arc ratio of permanent magnet are accomplished to increase the output power and to reduce the cogging torque. Finally, the output performances of AFER-NS and AFIR-S generator are compared with each other. For this study, 3D FEA is applied for the design analysis because of three dimensional electromagnetic structures.

• 한국전자파학회논문지
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• 제10권3호
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• pp.449-459
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• 1999

전파흡수체의 전자파산란 문제는 전송선로 근사방법과 유효매질 이론을 적용하여 매우 간단하게 표현할 수 있다. 이러한 방법은 전자장 수치해석 방법이 엄청난 계산이 필요한 것에 비해 매우 직관적이고, 간단하므로 전파흡수체 설계에 널리 사용되어져 왔다. 이 논문에서는 이러한 방법 자체가 가지는 근사의 한계 때문에 발생하는 적용한계를 유한요소법을 이용하여 검토하였다. 전송선로 근사방법은 λ 2p인 영역(여기에서, p는 전파흡수체의 배열주기, λ는 관심주파수 상한에서의 파장)에서 유효하다. 따라서 높은 물성을 갖거나 물리적 크기가 큰 구조의 전파흡수체는 흔히 이러한 조건을 만족치 않으며, 전자파 산란을 직접 수치해석적으로 계산해야 한다.

• 한국기계가공학회지
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• 제17권2호
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• pp.1-7
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• 2018

Recently, as interest in the internet of things has increased, a vibration energy harvester has attracted attention as a power supply method for a wireless sensor. The vibration energy harvester can be divided into piezoelectric types, electromagnetic type and electrostatic type, according to the energy conversion type. The electromagnetic vibration energy harvester has advantages, in terms of output density and design flexibility, compared to other methods. The efficiency of an electromagnetic vibration energy harvester is determined by the shape, size, and spacing of coils and magnets. Generating all the experimental cases is expensive, in terms of time and money. This study proposes a method to perform design optimization of an electromagnetic vibration energy harvester using an open source, big data platform.

• Journal of Magnetics
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• 제19권3호
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• pp.266-272
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• 2014

In this paper, we suggest reliability as a metric to evaluate the robustness of a design for the optimal design of electromagnetic devices, with respect to constraints under the uncertainties in design variables. For fast numerical efficiency, we applied the sensitivity-assisted Monte Carlo simulation (S-MCS) method to perform reliability calculation. Furthermore, we incorporated the S-MCS with single-objective and multi-objective particle swarm optimization algorithms to achieve reliability-based optimal designs, undertaking probabilistic constraint and multi-objective optimization approaches, respectively. We validated the performance of the developed optimization algorithms through application to the optimal design of a superconducting magnetic energy storage system.

• 대한기계학회논문집A
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• 제24권11호
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• pp.2732-2741
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• 2000

Combination of magnetic recording technology and optical recording technology such as Near Field Optical Recording is watched recently. In order to accomplish this technology, the development of an electromagnetic driven mm-sized mirror shifting laser beam in track direction have to needed. In Near Field Optical Recording System, shifting laser beam in track direction mean as fine tracking and means as coarse tracking. Therefore in Near Field Optical Recording, 2-stage actuator is composed of servo controller in reading or recording information on disc layer. In our research, through design and simulation process of driven mm-sized mirror, we arrange systematically design process of driven mm-sized mirror having good frequency transfer characteristics. Design and simulation processes included modal analysis of spring, calculation of magnetic moment according to the number of turns and geometric configuration of coil and magnetic circuit analysis meaning that calculation of magnetic flux density in air gap of magnetic circuit. After that we design and make parts of driven mm-sized mirror, assemble and evaluate our electriomagnetic driven mm-sized mirror. we compared design values with actual characteristic values and present solution scheme. Through these processes we performed manufacturing of an electromagnetic driven mm-sized mirror having good frequency-domain characteristics and high sensitivity characteristics.

• 유공압시스템학회논문집
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• 제8권1호
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• pp.1-9
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• 2011

The main design factors which effect on operating speed of linear actuator for valve operation are mass of plunger, electromagnetic motive force, inductance, and return spring, and these factors are not independent but related with each other in view point of design and electromagnetic theory. It is impossible to increase the operating speed by only change the value of any one design factor. The change of any one value results in change of any value related it in various design factors. This paper presents a speed increasing method of linear actuator using a solenoid design method by some governing equations which are composed of electromagnetic theory and empirical knowledge and permanent magnets as assistant material, and proved the propriety by experiments.

• Journal of Electrical Engineering and Technology
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• 제13권2호
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• pp.704-710
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• 2018

For the optimal design of electromagnetic device involving uncertainties in design variables, this paper proposes a new reliability-based optimal design algorithm for multiple constraints problems. Through optimizing the nominal objective function and maximizing the minimum reliability, a set of global optimal reliable solutions representing different reliability levels are obtained by the multi-objective particle swarm optimization algorithm. Applying the sensitivity-assisted Monte Carlo simulation method, the numerical efficiency of optimization procedure is guaranteed. The proposed reliability-based algorithm supplying multi-reliable solutions is investigated through applications to analytic examples and the optimal design of two electromagnetic problems.