• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.5
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• pp.707-714
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• 2000

In this paper, using third-order system of the PLL we'll analyze the aspect of flicker noise appearing troubles in the low frequency band. Since it is difficult to analyze mathematically flicker noise in the third-order system of the PLL, introducing the concept of pseudo-damping factor using the optimized second-filter has made an ease of the access of the flicker-noise variance. we'll show a numerical formula of flicker variance in the third-order system of the PLL which is compared with that of 1/f noise variance in the second-order system of the PLL.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.11a
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• pp.230-235
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• 1999

In this paper, Using third-order system of the PLL we analyze the aspect of flicker noise appearing troubles In the low frequency band. Since i. Is difficult to analyze mathematically flirter noise In the third-order system of the PLL, introducing the concept of pseudo-damping factor using the optimized second-filter makes an ease of the access of the flicker-noise variance. we'll show a numerical formula of flicker variance in the third-order system of the PLL which is compared with that of 1/f-noise variance in the second-order system of the PLL.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.9
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• pp.1663-1667
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• 2011

Voltage variation caused by large loads such as arc furnace and large motors, which use the large and instantaneous currents, can cause the voltage flicker. The flicker irritates the human's eyes and also has an adverse effect on protection device, rotating machine and electronic device etc, therefore the flicker needs to be managed effectively. Recently, the Korea power quality standard has been established on the IEC standards. This paper presents the flicker management standard for distribution power system and suggests the flicker transfer coefficients for Korea power system based on the IEC 61000-3-7.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.7
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• pp.1017-1024
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• 2017

The International Electrotechnical Commission(IEC) 61000-4-15 is a standard proposing techniques for a flicker meter test and measurement method. The IEC61000-4-15 ed1 announced in 1997 was not include tests for accurate verification. Also it was not explained flicker meter algorithm that can be directly applied to the other power systems. But the new edition of IEC61000-4-15 ed2 prescribes a variety of tests for verify flicker meter algorithm and it explains 'correction factor' used for measuring flicker in other power systems. It can measure flicker severity in 220V system by multiplying correction factor to the measured values with the 230V algorithm. This paper compared the method of measuring flicker severity in korea power system using the correction factor and the modified weighting filter, after verifying of digital flicker meter algorithm created by using matlab based on IEC61000-4-15 ed2.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.95-97
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• 2007

Large area flicker is one of the most annoying image defects, and it is an inherent characteristic of impulsively driven displays such as CRTs. Recently, LCDs have also adopted impulsive driving methods for improved motion picture quality, therefore LCDs can also show large area flicker. Existing metrics do not account for the non-linearity of human brightness perception. This paper presents an improved large area flicker metric to more accurately quantify large area display flicker performance.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.391-393
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• 2005

This paper studies flicker evaluation considering power quality disturbance. A flicker problem with light device irritates human's eyes. Also, the flicker problem has an influence on adverse effect such as rolling device and rotating device. However, a study of flicker evaluation is not complete. A flicker is measured and evaluated at monitoring point. But we consider power quality disturbances such as voltage sag and transient that cause fault and inverter/breaker switching. Power quality disturbances affects flicker evaluation. A flicker evaluation index increases. Therefore, we consider power quality disturbances. We detect voltage sag and transient using wavelet and evaluate flicker without flicker index including power quality disturbances.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.376-379
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• 2006

This paper studies flicker evaluation considering power quality disturbance. A flicker problem with light device irritates human's eyes. Also, the flicker problem has an influence on adverse effect such as rolling device and rotating device. However, a study of flicker evaluation is not complete. A flicker is measured and evaluated at monitoring point. But we consider power qualify disturbances such as voltage sag and transient that cause fault and inverter/breaker switching. Power quality disturbances affects flicker evaluation. A flicker evaluation index increases. Therefore, we consider power quality disturbances. We detect voltage sag and transient using wavelet and evaluate flicker without flicker index including power quality disturbances.

• Proceedings of the KIEE Conference
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• 2004.11b
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• pp.72-74
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• 2004

Nowadays there are many kinds of large scale loads and they make the power quality deteriorated. As the uses of nonlinear loads increase, there are the influences on the other kinds of loads (mainly light loads) in the same distribution system. Especially the voltage variation by the loads which draw the large and instantaneous currents can cause the appreciable light flicker. This is called the voltage flicker or, briefly, the flicker. This paper deals with the digital and time domain algorithm of measuring flicker based on IEC 61000-4-15 and the real time measurement of flicker through the proposed power quality monitoring system.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.310-312
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• 2002

The development of IEC 61400-21 provides firm basis for assessment of the impact of wind turbines on voltage quality. This paper presents analysis and modeling of the flicker emission of wind turbines. The paper concentrates on the theoretical aspects of the flicker algorithm, wind turbine characteristics and the generation of flicker during continuous operation of wind turbines. It also introduces a simplified assessment to limit the flicker emission.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.1
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• pp.1-7
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• 2018

IEC 61000-3-7 provides guidance for limiting flicker and enabling the connection of fluctuating load installations, that is, producing flicker in MV, HV and EHV power systems. In Korea, the flicker have been restricted by Japanese standard of ${\Delta}V_{10}$ method. ${\Delta}V_{10}$ was developed only for arc furnaces in 1960's. And now it is revealed that it is not suitable for application to other fluctuating load installations through many researches. $P_{st}$ which is a flicker index used in IEC 61000-3-7, indicates visual inconvenience due to voltage fluctuation across large range of frequency and can be applied to fluctuating load installations as well as arc furnaces. In this paper, we introduce how to calculate and assess flicker emission level for the individual fluctuating load installations connected in EHV system and how to manage the emission levels in the power system according to IEC 61000-3-7.