• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2043-2048
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• 2011

According to the statistical report from National Emergency Management Agency (NEMA) in Korea, the accident rate of closed switchboards in power systems occupies over 40%. In this paper, an integrated sensor module for monitoring the condition of closed switchboards is described. The sensor module monitors electro-magnetic (EM) wave, ultra-violet (UV) ray, heat and smoke generated by electrical discharges or insulation breakdown. The effective detection ranges were decided from experiment results; 100 kHz~10 MHz for EM wave, 220 nm~395 nm for UV ray and 0~$150^{\circ}C$ for heat, respectively. The prototype sensor module includes all functions above-mentioned in one device.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.406-409
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• 2004

Recently, many auto makers and OEM are now developing various telematics control units(TCU). TCU has an embedded OS and many user-friendly services inherently and frequently the driver operates the TCU on driving a car. Although the TCU has some accident resistive functions, secondhand accidental problem arose. Current Korean domestic TCUs have some interfaces such as push-button, touch screen, voice recognition and etc. But, because of operational complexity, technical limitation, it has not sufficient user-friendly interface. In this paper, to overcome this problem, haptic devices are considered. We present haptic devices and applications on the basis of that of U.S. Immersion co. and also BMW's iDrive technology.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.488-490
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• 1994

To meet the requirements of high performance and reliability as a industrial motor drive, we developed an integrated oil-line fault diagnosis and monitoring system which consists of DSP-based controller and PC-based MMI (Man-machine interface) program. The dedicated controller performs real-lime fault detections and protections. The MMI program monitors the on-line fault status of the drive system and offers full explanations of the fault name(WHAT?), deducible causes of the fault operation(WHY?), and chock points (HOW?) based upon the experiences of the expert. Also the TRACE data which was stored just before and after the accident can be scrutinized using MMI tools.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전기설비전문위원
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• pp.235-236
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• 2008

Charging of spacecraft occurs in plasma and radiation environment. Especially, we focused on an accident caused by internal charging in a glass material that was used as the cover plate of solar panel array, and tried to measure the charge distribution in glass materials under electron beam irradiation by using a PEA (Pulsed Electro-Acoustic method) system. In the case of a quartz glass (pure $SiO_2$), no charge accumulation was observed either during or after the electron beam irradiation. On the contrary, positive charge accumulation was observed in glass samples containing metal-oxide components. It is found that the polarity of the observed charges depends on the contents of the impurities. To identify which impurity dominates the polarity of the accumulated charge, we measured charge distributions in several glass materials containing various metal-oxide components and calculated the trap energy depths from the charge decay characteristics of all glass samples.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전력기술부문
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• pp.366-367
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• 2008

This paper deal with the study of the phenomenon of Ferroresonance in the 170kV Gas Insulated Switchgear(GIS). The Electromagnetic Transient Program(EMTP) was used to simulate the phenomenon of Ferroresonance and conducted the study of the transient over-voltage. An example power system, used in this study, have an accident that the ferroresonance phenomenon happens at MOFVT(Voltage Transformer). The simulation results notices that the secondary part of VT has to be connected by ferroresonance suppressor when the circuit breaker connected with grading capacitor is switched off.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전력기술부문
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• pp.51-53
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• 2007

The nuclear power plant uses the steam which occurs from reactor and T/G the drive. By the T/G in consequence of the fact that the electricity which is produced the power and supplies in transmission system. But, recently the transmission and generation system are placed under deregulation situation from domestic and foreign, the maintenance control is difficult with the accident or the breakdown which relates is increasing. Hereupon, considering for effect to the reactor core against trip element which it does apply a probability concept from the NRC of the United States and it study and the recognition for the importance of the switchyard which is a power equipment which will be revaluated. Hereupon using the American example, the reliability establishment method which is suitable in domestic and it searches it does.

• 한국안전학회지
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• 제31권5호
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• pp.16-21
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• 2016

The purpose of this paper is to conduct ETA on 15 components of power installations: the DS/LBS, LA, MOF, CT, PT, A/V meter, VCB, OCR, COS, PF, Transformer, Condenser(C), Grounding, Cable and Connector. To achieve that, power installations work flow and its components are categorized. Based on performance, human, environmental, management, and safety, this paper drew Initiation events (IE) and End states (ES). ETA is applied to the main functions of each component, and the end states that may occur in one initiation event are suggested. In addition, detailed classification was performed to induce various end states on the basis of the suggested initiation events. If the suggested IEs and ESs are applied on the basis of power installations event cases, it is expected to prevent the same kinds of accident and operate power installations safely.

• International Journal of Safety
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• 제1권1호
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• pp.1-6
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• 2002

It is important to control the high accurate position and force to prevent unexpected accidents by a robot manipulator. Direct-drive robots are suitable to the position and force control with high accuracy, but it is difficult to design a controller because of the system's nonlinearity and link-interactions. This paper is concerned with the study of the stabilization force control of direct-drive robots. The proposed algorithm is consists of the feedback controllers and the neural networks. After the completion of learning, the outputs of feedback controllers are nearly equal to zero, and the neural networks play an important role in the control system. Therefore, the optimum adjustment of control parameters is unnecessary. In other words, the proposed algorithm does not need any knowledge of the controlled system in advance. The effectiveness of the proposed algorithm is demonstrated by the experiment on the force control of a parallelogram link-type robot.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.789-793
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• 1992

For improving the power supply reliability and minimizing maintenance work of E.H.V. underground transmission line, new surveillance systems are strongly desired for use in the field of electric power transmission. For underground installation, high system reliability is required because E.H.V. cables, if an accident happen, can have a serious impact on social activities and human life. In answer to this requirement, applications of optical fiber transmission system have been widely developed in a variety of field. The main function of this system are cable fault location, oil leak detection, and surveillance of the cable circuit and tunnel condition.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.323_324
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• 2009

345kV Incheon Thermal Power Plant Transmission Line Collapse Analysis and Countermeasures. The Typhoon Galmaegi which had been formed in July 15, 2008 diminished into a tropical cyclone and cooled the air above the West Sea. The cooled air colliding with the warm inland air caused a strong whirlwind at some places in the west seaside; the whirlwind battered the 345kV Incheon Thermal Power Plant Transmission Line to be collapsed. The resistance against wind pressure, one of the key elements in transmission line engineering, is designed to endure the pressure corresponding to the maximum instantaneous wind speed. Before the above accident happened, no transmission line has ever been collapsed by a whirlwind. So this paper is aimed to analyze causes that collapsed 345kV Incheon Thermal Power Plant transmission line and to introduce countermeasures.