• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.158-165
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• 2005

KOGAS(Korea Gas Corporation) has about a hundred of local stations to supply natural gas to the city gas companies and the power stations. As some severe flow fluctuation phenomena are observed in several governor stations, the investigation about the reasons and factors which are relating to flow fluctuation has been started. Some field surveys hav been carried out and experimental studies have been performed to find the fluctuation mechanism. As a result, it is found that the flow fluctuation is related with the length of straight pipe in front of the meter, the size of the header pipe and the variation of demand at the city gas company and the power station. Furthermore. it is also proved that both the length of the transmitter cable and the status of the coating of signal transmission cable do not affect flow fluctuation, but the measurement range of the differential pressure transmitter influences flow fluctuation. On the other hand, as the averaging the flow fluctuation is converged to less than 0.1 % in almost all of the cases, it is concluded that the quantity of flow fluctuation do not relates to metering accuracy directly.

• Journal of IKEEE
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• v.26 no.4
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• pp.710-713
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• 2022

In this paper, a Goertzel-based algorithm was proposed to calculate the amount of power by estimating the harmonic components generated during charging of the electric vehicle up to a very high order, allowing it to be applied to a low-cos electricity meter with low computing power. Using the proposed algorithm, it is verified through simulation for a simple example signal that even large-order harmonics can be sufficiently considered when wattage is measured.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.290-292
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• 1998

The driving torque acting on a rotatable disk of watthour meter is proportional to the effective power. The aim of this paper is to show how the driving torque on a disk can be measured by a LVDT transducer. This driving torque is obtained by the theoretical computation. To verify the computated result, the LVDT as torque transducer, was used. A comparison is made between computed and measured torques.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.928-930
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• 2000

교류전력을 측정하기 위하여 알고 있는 직류전력과 동시에 비교할 수 있는 전력비교기를 개발하였으며 이 비교기를 기본으로 하여 정밀 전력계와 전자식 전력량계를 교정하거나 시험검사 할 수 있는 기준시스템인 전력표준기를 개발하였다. 특히 Push-Pull 기술을 이용한 전력비교기는 간단하며 정확도가 매우 높은 것으로 평가되었으며 전력비교기의 전체 불확도는 30 $\mu$ W/VA로 평가되었다.

• Journal of Sensor Science and Technology
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• v.15 no.3
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• pp.179-185
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• 2006

We have developed a noncontact temperature sensor using a silver halides infrared optical fiber. An infrared radiation from a heat source is transferred by a silver halides infrared optical fiber and measured by infrared sensors such as a thermopile and a thermal optical power-meter. The relationships between the temperature of a heat source and the output voltage of the thermopile and the optical power of a thermal optical power-meter are determined. The measurable temperature range using a thermopile and a thermal optical power-meter are from 100 to $750^{\circ}C$ and from 30 to $750^{\circ}C$ respectively. It is expected that a noncontact temperature sensor using infrared optical fiber can be developed for medical and industrial usages based on the results of this study.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.749-752
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• 2012

Recent social issues is energy issues, green computing has attracted attention. Active research on the power consumption of computer profiling is one of the various approaches for green computing. As a representative tool PowerAPI, PowerTop, JouleMeter, pTop, and EnergyChecker. These studies can be used to measure the power consumption of each computer device because it is based on a pure software. Based on this profiling process at the level of power consumption by performing the power consumption of each program can be analyzed. Therefore to identify the processes that consume a lot of power and control the total power consumption by reducing, also when designing the program, based on data profiling power enables the design of low-power programs, and ultimately can be oriented green computing. In this paper, by comparing and analyzing the associated representative studies, the ideal process level will draw on the characteristics of the power consumption profiler.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03b
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• pp.26-26
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• 2010

Line to ground faults or lightning strikes in electrical power systems produce high frequency overvoltages. With this reason, a wide band analysis of the ground impedance is necessary. In the paper, design of a wideband ground impedance meter which can measure the ground impedance in ranges from 65 Hz to 1.5 MHz is described. Also, a noise elimination method by a digital band-pass filter during measurement is proposed. The maximum measurement error of the meter is estimated 3 % in full ranges.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.9
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• pp.1516-1521
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• 2008

Recently, distribution load analysis using AMR (Automatic Meter Reading) data is researched in electric utilities. Load analysis method based on AMR system generates the typical load profile using load data of AMR customers, estimates the load profile of non-AMR customers, and analyzes the peak load and load profile of the distribution circuits and sectors per every 15 minutes/hour/day/week/month. Typical load profile is generated by the algorithm calculating the average amount of power consumption of each groups having similar load patterns. Traditional customer clustering mechanism uses only contract type code as a key. This mechanism has low accuracy because many customers having same contract code have different load patterns. In this research, We propose a customer clustring mechanism using k-means algorithm with contract type code and AMR data.

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.77-79
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• 1997

An induction watthour meter was designed for use on circuits in which the voltage and current are essentially sinusoidal. As the application of switching devices has been increased, the waveforms of voltage and current have involved the harmonics. Therefore, power energy involving voltage and current with the harmonics is supplied to the system and the registration error of watthour meter is existed. In this paper, we experimented on the error of watthour mesurement under the sinusoidal and nonsinusoidal input source.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.262-264
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• 2003

This paper develops an ADWHM(Advanced Digital Watt Hour Meter) based on RISK type'8bit micro-controller, which has voltage management data recording function, load management data recording function as well as the existing watt-hour data recording data function. It can enhance greatly the economics of the existing remote meter reading system. Also it can improve highly the quality of power supplied to the electric customer by minimizing the voltage management cost and by enhancing the efficiency of load management.