• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1974-1975
• /
• 2007

Continuous temperature monitoring and event recording provides information on the energized equipment's response to normal and emergency conditions. On-line temperature monitoring helps to coordinate equipment specifications and ratings, determine the real limits of the monitored equipment and optimize facility operations. Using wireless technique eliminates any need for special cables and wires with lower installation costs if compared to other types of online condition monitoring equipment. In addition, wireless temperature monitoring works well under difficult conditions in strategically important locations. Wireless technology for on-line condition monitoring of energized equipment is applicable both as standalone system and with an interface with power quality monitoring system. The paper presents the results of wireless temperature monitoring of switchgear at a power plant over a two-year period.

• Journal of the Korean Society for Precision Engineering
• /
• v.29 no.12
• /
• pp.1313-1320
• /
• 2012

Condition monitoring of the reciprocating compressor is important task. As a traditional method, health monitoring system of refrigerator depends on decision of a skilled person based on his experience. However, the skilled person cannot monitor all the compressors completely. If a sampled compressor is faulty, thousands of compressors manufactured at that place are regarded as faulty compressors. Therefore it is necessary to monitor all compressors in the production line. In the paper real time health monitoring system is developed based on high order time frequency method and artificial neural network. The system is installed in the mass production line. The result of the application has been very successful, and currently the system is working very well on the production line.

• Smart Structures and Systems
• /
• v.9 no.6
• /
• pp.473-487
• /
• 2012

GPS has become an established technique in structural health monitoring. This paper presents the application of an on-line GPS RTK system on the Zhujiang Huangpu Bridge (China) for monitoring bridge deck and towers movements. In this study, both the form and functions of movements of the deck and towers of the bridge under affecting loads were monitored in lateral, longitudinal and vertical directions. Such movements were described in time and frequency domains by determining the trend, torsion, periodical of the series using probability density function (PDF). The results of the time series GPS data are practical and useful to bridge health monitoring.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1972-1973
• /
• 2007

A field-oriented UHF system for on-line PD monitoring of transformers is designed, which has been installed inside the oil tank of a transformer. This system has successfully captured long intermittent discharge signals that hadn't been detected through conventional techniques, and solved the problem successfully. The results demonstrate that UHF technique has great advantages for on-line PD monitoring of transformers. By adopting the peak detection technique, it becomes easy and effective for the transplantation of the phase-resolved pattern recognition technique from conventional method to UHF method, and then to realize continuous on-line monitoring, source characterization and trending analysis.

• Proceedings of the KIEE Conference
• /
• 2003.07c
• /
• pp.1644-1646
• /
• 2003

This paper presents recent studies on the on-line insulation monitoring and diagnostic systems for transformers developed by HHI. Sufficiently high sensitivity and accuracy for practical use were achieved for the system, combined with communication networks to provide an on-line remote monitoring system. Several alarm criteria are formulated to enable a superimposed monitoring system to perform decisive action. The reasons for monitoring the condition and maintaining the health of electrical apparatus were discussed. The experience at the fields and the criteria for the judgment are also discussed in detail.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.590-593
• /
• 2004

This paper presents recent trends on the on-line monitoring and diagnostic systems for oil-immersed transformers. Specially, our system on YeoSu thermal power plant is introduced for high sensitivity and accuracy of ours. It is combined with communication networks to provide an on-line remote monitoring system. Several alarm criteria are formulated to enable a superimposed monitoring system to perform decisive action. The reasons for monitoring the condition and maintaining the health of electrical apparatus were discussed. The experience at the fields and the criteria for the judgment are also discussed in detail.

• International Journal of Aeronautical and Space Sciences
• /
• v.10 no.2
• /
• pp.34-42
• /
• 2009

Gas turbine performance diagnostics is a method for detecting, isolating and quantifying faults in gas turbine gas path components. On-line precise fault diagnosis can promote greatly reliability and availability of gas turbine in real time operation. This work proposes a GUI-type on-line diagnostic program using SIMULINK and Fuzzy-Neuro algorithms for a helicopter turboshaft engine. During development of the diagnostic program, a look-up table type base performance module are used for reducing computer calculating time and a signal generation module for simulating real time performance data. This program is composed of the on-line condition monitoring program to monitor on-line measuring performance condition, the fuzzy inference system to isolate the faults from measuring data and the neural network to quantify the isolated faults. Evaluation of the proposed on-line diagnostic program is performed through application to the helicopter engine health monitoring.

• Nuclear Engineering and Technology
• /
• v.54 no.2
• /
• pp.601-607
• /
• 2022

In recent years, monitoring of spent nuclear fuel inside dry cask storage has become an important area of national security. Muon tomography is a useful method for monitoring spent nuclear fuel because it uses high energy muons that penetrate deep into the target material and provides a 3-D structure of the inner materials. We designed a muon tomography system consisting of four 2-D position sensitive detector and characterized and optimized the system parameters. Each detector, measuring 200 × 200 cm², consists of a plastic scintillator, wavelength shifting (WLS) fibers and, SiPMs. The reconstructed image is obtained by extracting the intersection of the incoming and outgoing muon tracks using a Point-of-Closest-Approach (PoCA) algorithm. The Geant4 simulation was used to evaluate the performance of the muon tomography system and to optimize the design parameters including the pixel size of the muon detector, the field of view (FOV), and the distance between detectors. Based on the optimized design parameters, the spent fuel assemblies were modeled and the line profile was analyzed to conduct a feasibility study. Line profile analysis confirmed that muon tomography system can monitor nuclear spent fuel in dry storage container.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.12 no.6
• /
• pp.7-11
• /
• 2008

The helicopter flies at low level flight mode in its own operational range comparing to other aircraft categories. The low level flight means that the engine operates at variable atmospheric condition such as hot and cold temperature, snow, heavy rain, etc. Furthermore it may increase the entering possibility of engine foreign object damage particles like sand, dust, etc., i.e. this operating condition gives rise to damages of engine gas path components. An on-line condition monitoring program was developed by using SIMULINK, where measurement signals were simulated as an input module. The reliability and capability of the developed on-line condition monitoring were confirmed through application to a real helicopter engine health monitoring.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.11a
• /
• pp.163-166
• /
• 2008

The helicopter flies at low level flight mode in its own operational range comparing to other aircraft categories. The low level flight means that the engine operates at variable atmospheric condition such as hot and cold temperature, snow, heavy rain, etc. Furthermore it may increase the entering possibility of engine foreign object damage particles like sand, dust, etc., i.e. this operating condition gives rise to damages of engine gas path components. An on-line condition monitoring program was developed by using SIMULINK, where measurement signals were simulated as an input module. The reliability and capability of the developed on-line condition monitoring were confirmed through application to a real helicopter engine health monitoring.