• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.11
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• pp.72-76
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• 2003

The defected ground structure (DGS ) for microstrip structure can be used to protect analog/RF signal from SSN interference of digital circuits on PCB with common ground. However, the basic DGS gives rise to undesired emissions that may interfere with nearby circuitry due to the ground discontinuity. In this paper, we have proposed the modified structure, Corrugated DGS and the method to reduce the radiation by adding the lumped resistor on the proposed Corrugated DGS.

• Journal of electromagnetic engineering and science
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• v.5 no.4
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• pp.193-196
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• 2005

The DC power-bus for the PCB is loaded with metal walls on its selected sides and is characterized electromagnetically. This is a novel concept of approach to mitigate the spurious resonance and finally signal integrity problems. In particular, the peak at DC, which is always in the way to secure parallel-plates' EMC, can be completely removed by the proposed method. Through the findings of this study, the effect of metal-loading of the power-bus will be presented along with the impression that the suggested technique can tackle the headaches of signal integrity, ground bounce, EMIs.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.319-320
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• 2006

At this study, one of the electrical problems, arc characteristics according to loss of contact between a pantograph and a catenary, was analyzed. A characteristic of arc current is disappeared in a short period of time. Nevertheless, it has large current same as a surge, so that it has EMI/EMC problems. In the case of the electrical railway system, there is oscillation and de-wiring. The are current is generated by these problems. The result of this study can be used as a facility design to prevent a surge and needs to prove through actual field data in the main circuit of an electric train for a precise analysis about effect of are.

• Journal of Satellite, Information and Communications
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• v.12 no.4
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• pp.106-109
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• 2017

저궤도 위성의 배터리는 일반적으로 임무 및 식 구간에서의 부족한 전력 공급을 위해서 사용 되며, 버스 전압에 연결되어 있는 경우 출력 필터의 일부 기능을 담당하게 된다. 따라서 배터리의 주요 설계 요인은 전력 요구 분석을 통해 에너지 균형조건을 맞추기 위한 설계가 일반적이고, 배터리를 이용한 출력 전력 필터의 역할은 설계의 요인에 포함 되지 않는다. 하지만, 배터리는 전력 공급의 역할이외에도, 출력 전류의 변동이 극심하거나, 주기적으로 일정한 출력 변동을 발생하는 로드 등에 대한 필터 역할로써도 사용이 가능하다. 출력 커패시터를 배터리로 대체 할 경우 inrush 전류의 감소 및 추가적인 보호회로의 설계의 불필요 등의 장점을 가지고 있다. 배터리를 위성의 전력 공급을 위한 목적으로 사용하는 경우에는 전력 요구 분석을 통한 설계가 타당하나, 출력 로드 변동에 따른 영향을 줄이기 위해 필터로써 배터리를 사용하는 경우에는 사이즈 및 임피던스에 대한 추가적인 분석이 요구 된다. 따라서 본 논문에서는 저궤도 위성에서의 출력 전력 필터로 배터리를 이용한 설계 방안 및 성능 분석을 수행 하였다.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.6
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• pp.1001-1009
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• 1994

The present paper deals with a new developed sensor for measuring the time-varying magnetic fields and describes the experimental results of trasient magnetic field that takes place during the operations of electric appliance. The operation principle of the self-integrating magnetic field sensor by using coaxial cable is analyzed and a calibration investigation is carried out. The frequency bandwidth of the magnetic field measurement system is from 40 Hz to about 300 kHz. The magnetic field induced by the starting and/or operation of electric appliance mainly includes the odd harmonics such as the third, the fifth and the seventh harmonics. The magnetic field intensity caused during the operation of ultrasonic washer is inversely proportional to distance, this correspodns to induction component. As a result, it was known that the odd harmonics of magnetic field in the desing of electromagnetic shield employed for protecting electronic circuit and control devices have to be considered.

• Journal of electromagnetic engineering and science
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• v.15 no.3
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• pp.129-133
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• 2015

This paper presents the dosimetry of a resonance-based wireless power transfer (RBWPT) system for electric vehicles applications. The compact RBWPT system is designed to transfer power at 150-mm distance. The electric and magnetic fields generated by the RBWPT system and the specific absorption rate in the human body model, which stands around the system, are calculated. These analyses are conducted in two cases: the alignment and the misalignment between the transmitter and the receiver. The matching loops are adjusted to maximize the power transfer efficiency of the RBWPT system for the misalignment condition. When the two cases were compared for the best power transfer efficiency, the specific absorption rates (SAR) in the misalignment case were larger than those in the alignment case. The dosimetric results are discussed in relation to the international safety guidelines.

• Electrical & Electronic Materials
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• v.9 no.6
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• pp.626-631
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• 1996

현재 선진국에서는 전자기기에서 복사되는 전자파 및 이에 노출되었을 때의 내성에 대해서 동시에 규제하고 있다. 따라서 전자기기에서 사용하는 신호의 주파수가 점점 높아지고 회로가 집적화되므로 회로설계에 포함되지 않는 기생 소자의 영향도 연구되어져야 한다. 그러므로 이러한 조건을 모두 고려하여 초고주파 회로를 완전하게 설계제작할 수 있다면 이는 이상적인 기술이라 할 수 있을 것이다. 이것을 이루려면 많은 시간 동안의 연구와 분석을 통해 최종 생산물이 되기까지 대단한 노력이 요구된다. 본문에서는 초고주파 인쇄 회로 기판을 설계할 때 고려해야 할 점, 즉, 유전율 및 유전체의 두께, 소자 실장, 접지면 부착 및 회로의 패키지화에 관해서 소개하고자 한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.149-154
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• 2000

In this paper, we studied the relation between addition of carbon and electromagnetic wave absorbing properties of ferrite-rubber composite. The ratio of carbon was 7 wt%. As s result, it has been shown that the electromagnetic wave absorbing properties of ferrite-rubber composite are changed by the addition of carbon in composite. And, we can control electromagnetic wave absorbing properties of ferrite-rubber composite by the using of carbon.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.155-161
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• 2000

In this paper, we studied the relation between heat-treatment temperature of ferrite and electromagnetic wave absorbing properties of ferrite-rubber composite. The heat-treatment temperatures of ferrite are 1200 and $1300^{\circ}C$, 2 hr. As s result. it has been shown that the optimum heat-treatment temperature of ferrite for electromagnetic wave absorber are related to the chemical composition. And, we can control electromagnetic wave absorbing properties of ferrite-rubber composite by the control of heat-treatment temperature of ferrite.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.162-166
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• 2000

In this paper, we studied the relation between using amount of Ferrite and electromagnetic wave absorbing properties of ferrite-rubber composite. The variation of using amount of Ferrite have been 52 wt.% ~ 62 wt.%. As s result, it has been shown that the electromagnetic wave absorbing properties of ferrite-rubber composite are related to the using amount of Ferrite in composite. And, we can control electromagnetic wave absorbing properties of ferrite-rubber composite by the control of using amount of Ferrite.