• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.679-681
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• 2002

본 논문에서는 해석적 기법을 적용하여, 추진력과 부상력을 동시 제어하는 Planar Motor의 정밀 특성 해석을 나타내었다. 특히, 본 해석 모델은 가동자의 요크를 제거하기 위한 Halbach Array를 적용하였으며, 이에 대한, 정밀한 특성 해석을 위해 공간고조파 해석법도 제안한다. 또한, 해석해 검증을 위하여 유한 요소해석법에 의한 결과와 비교 분석을 하며, 이를 토대로 한 해석 모델의 동작 특성을 살펴본다.

• The Transactions of the Korean Institute of Power Electronics
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• v.19 no.5
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• pp.450-456
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• 2014

In HVDC converters that employ a line-commutated control, reactive power is absorbed by the rectifier and inverter terminals during AC/DC conversion. An AC filter usually consists of filters and large shunt capacitors to supply reactive power to the HVDC station. When STATCOM is used to supply reactive power to the HVDC system with AC filter, the low-order harmonics generated from STATCOM can result in a resonance between the shunt capacitor and AC network. Therefore, a control strategy based on selective harmonic elimination is adopted to minimize the low-order harmonics from STATCOM. The cancellation of harmonic instabilities is verified through simulations in PSCAD/EMTDC.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.2
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• pp.38-44
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• 2002

The increasing use of non-linear loads such as power electronics draw highly distorted currents from the utility system High harmonics current, and voltages will cause equipment damage and disturb the plant operation. The application of phase shifting transformers can be a very cost-effective method of harmonic treatment where multiple harmonic sources ice in operation. In this paper simulation results used the EDSA harmonics analysis program verifying the effects of a phase shifting transformer for harmonic elimination are presented.

• The Journal of the Acoustical Society of Korea
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• v.10 no.3
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• pp.72-82
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• 1991

The Magnetic noise generated in three phase induction motor are investigated. Total noises measured by using JEM-1313 code and sound length method and the experimental formulae are derived of magnetic fk={K+$\frac{Z_s}{P}$(1-S)}f[Hz] noise is measured in the stator of induction motor except rotor supplied from power source and their datum are analyzed and compared with one another. The experimental value of magnetic noises are equal to the theoretical value at 1440[Hz] and 1560[Hz]. The biggest magnetic harmonic is generated at 1560[Hz].

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.6
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• pp.906-915
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• 1994

Line-Current harmonics resulting from ac to dc power conversion interfere with power system operation and reduce power factor, hence resulting in increasing power source unnecessarily. This study describes a 3 phase phase-controlled converter eliminating low frequency harmonics in the output by inserting notches. Notch points are calculated by Newton-raphson method, The impacts of the choppings on ac and dc sides are analyzed in the steady state. Potential applications of the study are dc motor controls, high power dc power supplies for telecommunications, static var compensators and HVDC.

• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.102-106
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• 2005

본 논문에서는 연료전지 전원시스템에 적합한 전류형 고주파 링크 DC-AC 컨버터를 제안한다. 제안된 전류형 고주파 링크 DC-AC 컨버터는 전류형 풀-브릿지 인버터, 능동 고조파 필터, 고주파 링크 변압기, 사이클로 컨버터로 구성된다. 1차측의 전류형 고주파 풀-브릿지 인버터는 정현파 PWM에 의해 변조된 전류펄스를 영전류 스위칭과 함께 발생시키고 두 개의 양방향 스위치와 출력 필터 캐패시터만으로 구성된 사이클로 컨버터는 분리형 단상 60Hz 정현파 전압을 출력한다. 입력단에 연결된 능동 고조파 필터는 연료전지로부터 유기된 저고조파 전류를 배터리 또는 수퍼캐패시터같은 장시간의 에너지 저장장치 없이 제거한다.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.9
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• pp.178-185
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• 1994

This study describes a software-based conrol methodology eliminating low-frequency harmonics from a 3.phi. phase-controlled converter. The converter topology used in the study is capable of the phase current lagging and dealying with respect to the phase voltage. Low order harmonics are eliminated in the dc output voltage by introducing notches. The good agreements between the simulation and experimental resuls show the validity of the proposed scheme. The use of the software-based control scheme results in a simple and flexible realization of the system.

• 전기의세계
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• v.44 no.11
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• pp.21-27
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• 1995

최근 전력변환장치 및 전동기 드라이버에서 전력용스위칭 소자의 사용 증가와 관련하여 고조파 저감 및 역율개선에 대한 관심이 증가되어지고 있다. 더욱이 유럽 및 미국에서는 전력변환 장치에 대한 고조파 저감 및 역율개선에 대한 규격들(IEC 555-2, IEEE 519)이 정립되어 많은 전기.전자 산업. 가전 제품들이 이 규격에 근거한 전고조파 왜형(total harmonic distortion)에 대하여 제한을 받고 있다. 적절히 설계되어진 역율개선(power factor correction) 회로들은 공급 전원과 동상이며 정현파형상의 전류를 상용 전원에 제공하며 규격에서 제한된 고조파 성분을 제거하는 역할을 한다. 본고에서는 이들 고조파 제한에 관한 규격에 대하여 고찰하고 전력 변환 장치에 대한 입력전원의 고조파 저감 및 역율개선에 대하여 지금까지 개발 및 연구되어진 PFC 회로 및 제어기법에 대하여 고찰하고자 한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.8
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• pp.1751-1758
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• 2003

This paper describes speed control of a permanent split capacitor single phase induction motor using SHE PWM inverters. The inverter is controlled by V55 microprocessor and its range is larger than other systems. Due to the V/F control with SHE(Selected Harmonic Elimination) PWM, continuously variable speed is attained and THD(Total Harmonic Distortion) is decreased. This is verified by simulations and experimental results.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.566-571
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• 2009

In this paper, microstrip bandpass filter combined DCRLH metameterial-cells with a hairpin resonator is designed and fabricated to be transferred only fundamental passband signal, and removed a spurious resonant mode occurring when filter design using a microstrip transmission line is done. The bandpass filter is composed of CCRLH hairpin resonator and DCRLH interdigit metameterial-cells. The hairpin resonator with CCRLH property is implemented between two DCRLH interdigit metameterial-cells with DCRLH property, which is parallel to input port and output port. The interdigit metameterial-cells suppress spurious harmonics occurring on the higher order frequency and improve a filter performance. Insertion loss of the fabricated microstrip bandpass filter on the passband from 1.91GHz to 2.41GHz is 0.2dB, and attenuation on the stopband from 3GHz to 7.7GHz is bellower than -30dB. Therefore, this filter has a good performance for both mobile communications of WCDMA and wireless internet of WiBro.