• 조명전기설비학회논문지
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• 제17권6호
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• pp.89-94
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• 2003

최근 에너지의 효율적인 사용을 위해 제작되어 상용화되고 있는 전력변환장치는 기기 특성상 기본파의 n배 주파수를 갖는 고조파를 발생시키고 있다. 이렇게 발생된 고조파는 기본 정현파를 대상으로 제작된 여타 기기의 작동에 악영향을 끼치므로 반드시 제거해야할 요소로 문제시되고 있다. 본 논문에서는 현재 정보화 시대를 맞이하여 증가되고 있는 PC를 대상으로 고조파 발생량을 측정$.$분석 하였으며 그에 따른 가장 효과적인 고조파 저감대책을 제시하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.439-442
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• 2000

An adaptive nonlinear control of a brushless direct drive motor(BLDDM) is proposed. Comparing to the traditional PMSM the direct drive motor has smaller number of per pole and per phase slots to provide higher torque in low speed. This generic construction generates flux harmonics and finally results in unwanted torque harmonics. To control the speed a feedback linearization method is applied by choosing the $i_{ds}$ and $\omega_{m}$ as the output variables. The control of the flux harmonics is provided by using a flux observer with MRAC technique. As shown in the simula-tion results the proposed nonlinear speed controller has a good speed response in the steady state and robust to the flux variation

• 조명전기설비학회논문지
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• 제14권3호
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• pp.81-87
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• 2000

전력변환기와 같은 비선형 부하의 사용증가는 전원 전력설비시스템에 고조파을 발생시킨다. AD/DC 변환설비는 전력시스템에서 중요한 고조파 발생원이 되고 있다. 고조파를 포함하는 전류와 전압은 전기설비에 고장과 오동작등과 같은 나쁜 영향을 미친다. 고조파 문제를 해결하는 일반적인 방법으로는 고조파 필터룹 사용한다. 본 논문에서는 EDSA 고조파 분석 프로그램을 사용하여 고조파를 제거하는 동조필터를 설치하여 그 효고를 검증하였다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권8호
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• pp.441-448
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• 2002

Harmonics studies have been an important aspect of power conversion system analysis and design in recent years. Harmonics using power conversion device, have a harmful effect on power qualify. Nonlinear load such as converter causes harmonic and effects self & other system. There are linear and nonlinear loads in the end-user application. For filter design to reduce harmonics, it is important to understand how loads interact with each other. In this paper, effects on the power conversion system at the low voltage local bus are discussed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.252-254
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• 2000

For many years, electric utility has used sustained interruption rates as a reliability index. Today, however, many electricity consumers are adversely affected by more subtle voltage disturbances such as harmonic distortion. This paper deals with observations of events that occur in the Dimmer circuits and phase control which could affect harmonics problem to the commercial power system. In order to reduce the effect of harmonics and design filters, Solid State Relay Dimmer(SCRs or TRIACs) and Noise Filter are described, and the effects of harmonics is also analyzed. IGBT Dimmer which is appropriate method to reduce harmonics and improve efficiency is introduced.

• 전기학회논문지
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• 제64권1호
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• pp.149-158
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• 2015

This paper proposes a subband filtering technique to the MUSIC and the ESPRIT algorithm for estimating the magnitude and frequency of the harmonics of power signal. In proposed method, the input power signal is decomposed to the odd harmonics and the even harmonics respectively by the filter bank system. The amplitude and the frequency estimation of the decomposed harmonics are carried out using the MUSIC and the ESPRIT method. Subband filtering can reduce the autocorrelation matrix size of input data, and spectrum leakage between adjacent harmonics. Therefore, this subband technique has advantage in computational cost and estimation accuracy compared to fullband MUSIC and ESPRIT. To demonstrate the performance of the method, computer simulations are performed to the synthesized input signal, and experiment results are compared in subband and fullband cases.

• Journal of Magnetics
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• 제18권2호
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• pp.216-219
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• 2013

In this paper, the influence of inverter switching harmonics on iron loss and PM loss of Permanent Magnet Synchronous Motor (PMSM) is numerically investigated by Finite Element Method (FEM). In particular, nonlinear FEM is applied for a multi-layered PM Synchronous Motors (PMSMs), Interior buried PMSM (IPMSM) and PM assisted Synchronous Reluctance Motor (PMa-SynRM), which are adoptively designed and compared for Electric Vehicle (EV) propulsion. In particular, iron loss and PM eddy-current loss under the real current waveform including the carrier harmonics from inverter switching are numerically analyzed with nonlinear FEM by considering the skewed stator structure employed for minimizing spatial harmonics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.359-361
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• 1987

It is known that the reactive component of AC power in the Power system gives no energy to outside and causes enlargement of power apparatus, voltage fluctuation and unstability of power system. The power conversion system and control system which are composed of power semiconductor devices such as Thyrisor, transistor, GTO and so on have been appeared as new sources of Harmonics. So the reduction of harmonics in power semiconductor system is one of impending problems on the point of energy conservation and improvement of power factor. This paper treates the fundamental review of the harmonics reduction by Current type PWM-Inverter. This Inverter-detects not only the fundamental wave but also that of all harmonics created in the power semiconductor system and is scheduled to control by sampled value.

• Journal of Magnetics
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• 제3권4호
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• pp.120-122
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• 1998

The higher order harmonic components of magnetostriction during ac magnetization in 3% SiFe are measured as a function of the magnetizing angle respect to [001] axis using a constructed laser interferometry. The magnetostriction with magnetizing angle from [001] axis agrees ith the calculation based on domain reorientation. The relative amplitudes of odd and even harmonics respectively for magnetic induction and magnetostriction decrease with the order of harmonics, accompanying the contraction of the amplitudes. The contraction of harmonics order of magnetostriction harmonics is shown to be the even number times of that of magnetic induction.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.131-133
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• 2005

Recently the harmonic generation has declined electricity quality and has bad influence on the electrical installation including OA(Office Automation), FA(Factory Automation), IT(Information Telecommuni-cation) devices and so on. The study of harmonics be greatly interested in diagnosis accident with harmonics was not merely guesswork but clarify the cause by experimental data at these days. Therefore, it is necessary development of AC power source for correct experiment with reliable data. In this paper, we realized the AC power source that can produce and compose harmonics for analysis of accident with harmonics.