• Journal of the Institute of Convergence Signal Processing
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• v.3 no.2
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• pp.45-52
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• 2002

EMI(Electromagnetic Interface) is a measure of electomagnetic radiation from equipment in the range of 10KHz to 3GHz, and can cause unexpected reactions of electronics/electrical equipment. In this study, for safe and stable communication operation, a STGU(System Timing Genetation Unit), which is a 2.5Gbps SDH System and a major EMI source, was employed to simulate electromagnetic interface. In On-Site test, the power of fundamental frequency of EMI of interest and its harmonics were measured. Also, a low pass filter at cut-off frequency of 2GHz was specifically designed to minimize the effect of EMI between electronic components. When the low pass filter was implemented within the STGU, the power of EMI decreased more than 20dBm. Finally, when TIE and MTIE, two important quality measure in synchronous reference clcok, was assessed, ITU-T G8l3 requirements are satisfied.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.53-56
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• 2000

An Electrical equipment is the noise source which makes a noise. So the optimally designed filter should be inserted in the equipment in order to reduce the noise. The noise source impedance is varied according to the frequency It effects on the CE noise. Knowing the magnitude of its impedance and inserting an EMI filter in the equipment we can estimate the insertion loss of the filter. SO it helpful in designing the EMI filter. The measurement method of a noise source impedance is proposed and verified by experiment.

• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.2159-2161
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• 1997

This paper presents the investigations and the reduction methods for EMI in the Elevator(E/L) system. In the large capacity E/L. Power factor controlled IGBT converter is used, so that the conducted EMI level is mostly determined by a high frequency input current. We suggest the low cost EMI countermearsure for E/L system using by a LCL filter ed a low cost noise filter.

• Smart Structures and Systems
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• v.22 no.1
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• pp.57-70
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• 2018

For the long-term structural health monitoring of civil structures, the effect of ambient temperature variation has been regarded as one of the critical issues. In this study, a principal component analysis (PCA)-based algorithm is proposed to filter out temperature effects on electromechanical impedance (EMI) monitoring of prestressed tendon anchorages. Firstly, the EMI monitoring via a piezoelectric interface device is described for prestress-loss detection in the tendon anchorage system. Secondly, the PCA-based temperature filtering algorithm tailored to the EMI monitoring of the prestressed tendon anchorage is outlined. The proposed algorithm utilizes the damage-sensitive features obtained from sub-ranges of the EMI data to establish the PCA-based filter model. Finally, the feasibility of the PCA-based algorithm is experimentally evaluated by distinguishing temperature changes from prestress-loss events in a prestressed concrete girder. The accuracy of the prestress-loss detection results is discussed with respect to the EMI features before and after the temperature filtering.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.533-534
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• 2007

This paper investigates impulsive noise from a pole transformer in low voltage distribution system for power line communication. EMI noise from the pole transformer is indicated from the experiment. The noise has certain characteristics because it is caused by partial discharge. The noise level is above -35dBm without a filter. Therefore, the filter which is made of ferrite is used in order to eliminate the noise. the noise filters should be applied to both the phase line and the neutral line. Otherwise, It is likely to have little overall impact on elimination of noises. the performance of filter is verified with various experiments. In conclusion, the equivalent circuit of power line communication including noise source is described as a lumped circuit.

• Proceedings of the Korea Information Processing Society Conference
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• 2024.05a
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• pp.453-454
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• 2024

전기자동차의 자율주행 기술의 수요 증가로 안정성을 위해 Redundant Design 이 브레이크 제품에 요구되고 있다. 이러한 Design 으로 인해 발생하는 Noise 와 제어를 위한 성능을 고려한 Filter 를 설계하고자 한다.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.6
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• pp.546-555
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• 2001

In this paper filtering techniques to reduce the adverse effects of motor leads on high-frequency PWM inverter fed AC motor drives are presented. The filter was designed to keep the motor terminal from the cable surge impedance to reduce overvoltage reflections ringing and the dv/dt, di/dt, at the motor terminals. Specially the output filter is used to limit the rate of the inverter output voltage and reduce common mode noise to the motor, The performance of the output filter is evaluated through simulations and experiment on PWM inverter-fed AC motor drive. An experimental PWM drive system reduction of conducted EMI was implemented on an available TMS320C31 microprocessor control board Finally, experimental result shows inverter output filter reduces more common mode voltage than low pass filter also reduce overoltage and ringing at the motor terminal.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.49-55
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• 2016

To separate the CM and DM noise in the EMI generated in various electrical electronic systems, passive and active separators have been researched. These separators are an important part of an effective active EMI-filter. The passive separator has some advantages, in that it is easy to realize at a low price and its structure is very simple. However, its major drawback is that its accurate inductor realization and accurate core selection are very difficult. The active separator is smaller in size and more accurate, but its main drawback is that an op-amp which has a broad band frequency response is necessary, its cost is high, and a DC power circuit is required. This paper compares the characteristics of EMI filters which apply the existing passive separator and proposed active separator. It was concluded that an active separator is needed for expensive and accurate equipment, whereas a passive separator is sufficient for inexpensive and general purpose EMI filters.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.175-179
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• 2009

this paper proposes a filter design that makes to be satisfied EMC spec. in reliability test of analogue switch for electronic equipment and air conditioning load unit. A designed electromagnetic wave filter was applied to minimize an mutual interference and surrounding environment and improve the product's quality being satisfied to EMC standard. By simulation, using a spectrum analyzer at the 30MHz~1GHz band, ISO/JASO standard frequency range, and simplified EMI chamber, energy distribution of a specific frequency band was analyzed and the capacity of the element which composed the filter was determined in order to implement the most suitable electromagnetic wave filter.In fact, it was certificated that noise decrease by filter addition to the analogue switch for electronic equipment and air conditioning load unit in Certification Authority, and confirmed that the unit is carried out a normal action without electromagnetic wave interference.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.308-309
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• 2011

최근 PDP와 LCD등의 FPD용(用) 전원 시스템에 고효율화, 고밀도화 및 Slim화를 위한 전원 회로 기술이 요구됨에 따라 이를 실현하기 위해서는 전원 회로를 구성하는 각 컨버터의 최적 Topology 확보뿐만 아니라, 전원 회로에 사용되는 부품들에 대한 차별화된 핵심 부품 기술 확보가 필수적이다. 이러한 요구에 부합하기 위해서 FPD용(用) 전원에 적용되는 자성부품구조도 기존의 성능을 유지하면서 박형화, 저비용화 및 자동 권선화를 구현할 수 있는 방안에 대한 연구가 필요하다. 본 논문에서는 LED-TV용 전원장치의 EMI Filter부의 개발사례 및 특히 EMI Filter부의 대책부품 중에 자동권선형 공통모드 초크의 개발동향 및 사례에 대해서 소개하고자 한다.