• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.1
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• pp.44-49
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• 2002

In recent years, diagnostic techniques have been investigated to detect a partial discharge(PD) in a high voltage electrical equipment. Because PD signal is very sensitive and difficult to suppress strong noises such as narrow-band radio frequency noise and random noise, the accuracy and credibility of PD measurement might be influenced by surrounding interference. Using the technique of PD detection by electromagnetic wave, we have studied the characteristics of both PD and substation-in interference signal. Also, we propose a wavelet packet transform based technique to perform a feature extraction from the interference and PD signal and a classification of the extracted features. The results show that time-frequency characteristics between PD and interference can be obviously distinguished. It is helpful for the development of the insulation diagnosis technique.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.12
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• pp.74-83
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• 2014

This paper proposes a study on the configuration of balancing of plant(BOP) and implementation of battery management system(BMS) functions for vanadium redox flow battery(VRFB) and propose a method consists of sensor and required design specifications BOP system configuration. And it proposes an method of the functions implementation and control algorithm of the BMS for flow battery. Functions of BMS include temperature control, the charge and discharge control, flow control, level control, state of charge(SOC) estimation and a battery protection through the sensor signal of BOP. Functions of BMS is implemented by the sensor signal, so it is recognized as a very important factor measurement accuracy of the data. Therefore, measuring a mechanical signal(flow rate, temperature, level) through the BOP test model, and the measuring an electrical signal(cell voltage, stack voltage and stack current) through the VRFB charge-discharge system and analyzes the precision of data in this paper. Also it shows a good charge-discharge test results by the SOC estimation algorithm of VRFB. Proposed BOP configuration and BMS functions implementation can be used as a reference indicator for VRFB system design.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.5
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• pp.12-18
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• 2000

This paper describes the analysis of ultrasonic signal and partial discharge(PD) signal patterns for each location of particle in GIS. The characteristics of the ultrasonic signal and PD signal patterns for each location were as follows; in case of particle on the electrode, large ultrasonic signals and large PD signals occurred in positive half-cycle periodically; in case of particle on the spacer, ultrasonic signals and large PD signals occurred in negative half-cycle periodically; in case of the free moving particle, ultrasonic signals and large PD signals occurred by collision non-periodically. As a result, it was confirmed that particle in GIS could be located by the comparison and analysis of ultrasonic signal and PD signal patterns.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1996.11a
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• pp.122-124
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• 1996

This paper describes a diagnosis of distribution cable splices by analysis of ultrasonic signals which are generated by partial discharge. A method of ultrasonic signal was used to detect internal defects in distribution cable splices. It is possible that analysis of ultrasonic signal predicts failure by partial discharge generated in distribution cable splices.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.404-406
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• 2001

This paper is detecting a partial discharge(PD) using antenna. The wavelet transform is applied for the analysis of PD pulse signal. It is difficult to identify PD signal using electromagnetic waves detected by antenna. And so we can removed noise of PD signal using wavelet de-noising method.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.467-469
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• 2001

This paper presents an efficient location estimation methodology for a partial discharge(PD) source in the power transformer. The methodology previously proposed is not suitable for locating a PD source because the ultrasonic signal with medium attenuated through the inner structure. In general, the propagation characteristic of ultrasonic signal with medium is different. Therefore, using this propagation characteristic, we can detect the location of PD source. In this paper, the proposal algorithm finds the PD source using three sensors attached to one side of the transformer without attenuation of the ultrasonic signal and applying the neural network based geometrical method. The proposed methodology demonstrates the effectiveness and validity on an experimental transformer.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1445-1446
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• 2007

In this paper, we have studied for analysis of the partial discharge(PD) signal in power transmission line. The PD signal has estimated as detected signal accumulation of a PRPDA method by using Labview, and analyzed with neural-fuzzy algorithm. With practical PD logic implementation of theoretical detected system and hardware implementation, the device for Hipotronics Company's 22.9kV or 154kV setup have generated and then have applied with 18kV,20kV with 1:1 time probe. It's also used the LDPE 0.27mmt (scratch error 0.05mmt) to sample for making PD. Our new class of PD detected algorithm have also compared with previous PRPDA or Neural Fuzzy algorithm, which has diagnose more conveniently by adding numerical values.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2178-2180
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• 2001

This paper is the study for the separating noise signal that is the greatest problem in ultrasonic signal measurement which is one of the method of estimation of partial discharge signals location. Because we can measure the number and location of signal, it is possible to distinguish between the signal of partial discharge and the external noise. Therefore, we can develop the credibility of detecting of insulating deterioration in transformer.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.423-425
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• 2004

This raper deals with a platform for diagnosis monitoring of partial discharge based on Java virtual machine. This platform is designed for estimating diagnostic parameters of partial discharge signal and displaying Web-page on operating status. For Web-service, hardware of platform is based on a Strongarm processor and software base is designed on Linux and java virtual machine.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.10
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• pp.879-883
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• 2009

This paper was provided to help in detecting defects in power transformer. For this purpose, a partial discharge cell was designed and manufactured as a discharge source to simulate particle defected paper-oil insulation in power transformer. Experimental set-up for measuring PD signals was described. Magnitude of electromagnetic wave signals and corresponding amount of apparent discharge were measured simultaneously against phase of applied voltage to the discharge cell. Frequency range and pattern of PRPD(Phase Resolved Partial Discharge) of partial discharge signals were examined and analyzed. The results will be contributed to build the defect database of power transformer and to decrease the substation faults.