• 대한전기학회논문지
• /
• 제40권6호
• /
• pp.630-637
• /
• 1991

For the measurement of time-varying electric fields and related quantities, a field sensor should be sensitive to the field to be measured, and also designed having an accurate transfer function. In this paper, a theoretical model which adequately describes the operation principle and design of the sensor is presented. A calibration and/or correction technique of the sensor is also studied which enables a precise determination of the response of the sensor to an electric field. As a result, the developed electric field sensor and measuring system are known to be accurate within a bandwidth from a few Hz to 200 MHz. It is found that the sensor can be used directly in the measurement of very fast transient voltages and time-varying electric fields occurring during disconnector operations in a gas-insulated substation. It may be useful also for the study on the electromagnetic environmental parameters.

• 전기학회논문지
• /
• 제64권9호
• /
• pp.1281-1287
• /
• 2015

We report the characteristics and differences of two types of attenuation measurement methods for electromagnetic partial discharge signal in GIS. The pulse method is to measure the attenuated waveforms in time domain and coverts them into frequency domain to get the attenuation spectra of given GIS section. This method simulates the real partial discharge signal. The frequency swept continuous wave method can obtain attenuation spectra directly so that it gives attenuation with low noise floor and simplicity. We show that both methods are effective and exchangeable because the attenuation results measured by two methods have similar trends

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 하계학술대회 논문집 E
• /
• pp.1653-1655
• /
• 1998

In this paper, measurement and analysis of ELF electric and magnetic fields in the vicinity of 22.9[kV] distribution line have been performed. The height of measuring point from the earth's surface was 1[m], and the distance between the device and the operator was more than 3[m]. The experiments have been carried out by lateral profile, and we have made use of FIELDS program for the sake of comparision the experimental data with the theoretical value. Electric and magnetic fields intensity were strong under a distribution line, and were inversely proportional to lateral distance. The profiles of electric field were M shape and those of magnetic field were $\cap$ shape. Electric and magnetic fields intensity were increased with increasing the measurement height.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
• /
• pp.1197-1198
• /
• 2006

The wind turbine system, one of the distributed resource, has a large effect on the distribution system. because windfarm is located in the end part of the distribution system, the hilly section and the shore, which is easy to obtain the wind energy, it is difficult to manage the voltage and the power quality. Therefore this paper deals with the measurement and assessment of power quality characteristic of wind turbines with IEC 61400-21.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 하계학술대회 논문집 E
• /
• pp.1827-1829
• /
• 1997

In this paper, measurement and analysis of ELF electric and magnetic fields due to a transmission line have been carried out and the power frequency field strength measuring system is designed. In order to evaluate electric and magnetic fields associated with 60 Hz electric power transmission and distribution lines, the actual survey near a transmission tower has been made and analyzed. It may be inferred from these results that the maximum electric and magnetic fields strength in the vicinity of a line tower do not exceed 3.5[kV/m] and 20[${\mu}T$]. The results of the field measurements agree with limits and guidelines recommended by various authorized international institutes.

• Structural Engineering and Mechanics
• /
• 제12권4호
• /
• pp.449-457
• /
• 2001

In the design of industrial chimneys and towers, structural engineers must assume a level of the inherent damping in the structures. In order to better estimate the dynamic response of those structures, actual damping was measured from wind-induced vibration signals of chimneys and towers and its characteristics with respect to the response levels, the structural systems, and the wind direction were discussed. Damping ratio and natural frequency for three chimneys and two towers were calculated using random decrement technique.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2001년도 춘계학술발표회요약집
• /
• pp.241.2-241
• /
• 2001

• 전기저널
• /
• 통권397호
• /
• pp.51-51
• /
• 2010

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2005년도 추계학술발표회
• /
• pp.971-972
• /
• 2005

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
• /
• pp.891-898
• /
• 2009

A high rock embankment by means of dynamic compaction has hardly carried out in domestic area. For the successful accomplishment of such a high rock embankment, construction quality and measurement control are conducted. Plate loading tests are carried out to verify the bearing capacity and safety against the long term settlement. In addition, settlement of each layer is measured in order to verify the effect of dynamic compaction and to predict long term settlement.