• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1090-1095
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• 2000

발전기에 직류 전압을 인가하는 여자제어 시스템(exciter)은 여자 방식에 따라 간접 여자 방식과 직접 여자 방식으로 분류할 수 있다. 그러나 여자제어 시스템의 세계적인 추세는 직접 여자 방식을 채택하고 있으며, 기존의 설치된 간접 여자 방식도 직접 여자 방식으로의 교체를 추진하고 있는 실정이다. 본 논문에는 500 MW 발전기의 간접 여자제어 시스템을 직접 여자제어 시스템으로의 교체를 위해 수행된 축계 진동해석과 설계 검토 사례를 소개코자 한다. Steady 베어링의 설치 여부를 위한 설계 기준은 축계 진동해석 결과에 바탕을 두고 있으며 steady 베어링의 선정에는 안정성을 이유로 tilting pad 베어링을 선택하였다. 해석 결과를 바탕으로 실제 축계를 설계, 제작하여 운전한 결과 양호한 결과를 얻을 수 있었다.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.2
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• pp.74-80
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• 2014

Generator protection device has to detects an internal fault conditions in generator and abnormal operating conditions must be due to the hazards. Loss of excitation may cause generator itself failure as well as serious operating problem in power system, and then requires an appropriate response of generator protection device. Details modeling of generator control system and analysis of transient states in generator are important for optimal operation in power plants. In addition, the fault simulation data are also used for testing the characteristics of IED. In this paper, the hydro generator control system using PSCAD/EMTDC, visual simulation for power systems, was modeled. The generator control system which is composed of generator, turbine, exciter, governor was implemented. The parameters of generator control system model were obtained from field power plant. Loss of excitation simulations were performed while varying the fixed load. Several signals analysis were also performed so as to analyze transients phenomena.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.147-149
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• 1999

This paper deals with the determination of generator/exciter model parameters for a Cheju Hanlim steam turbine unit. Using the recorded data from the generator characteristic tests, the model parameters have been derived and verified by comparing the simulation results and recorded data. In addition to it, the closed-loop performance of voltage control on no-load condition has been assessed in the frequency domain by taking advantage of derived generator/exciter model parameters.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.10
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• pp.924-933
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• 2011

The possibility of noncontact excitation of vibrations in a shaft was investigated in order to enable online structural health monitoring of a shaft during its rotating condition without stop operation. The proposed noncontact exciter was devised to exclusively generate one of two shaft vibration modes, so called longitudinal and flexural. Using the prototypes and a lot of experiments on them, it was proven that bias magnetic field, exciting voltage, center frequency, and geometry of yokes have crucial impacts on its output characteristics.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.133-134
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• 2006

A cylindrical capacitive displacement sensor (CCS) was developed and applied for monitoring end milling processes. Dynamic characteristics of a spindle-assembly were measured using the CCS and a designed magnetic exciter. The technique to extract the spindle displacement component caused only by cutting from the measured signals using the CCS was proposed in the paper. Using CCS signals and FRF (Frequency Response Function) derived from dynamics of the spindle tool system, dynamic cutting forces are estimated quantitatively.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.46-50
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• 2002

In other to evaluate the static and dynamic stiffness of machine tool structure, the accuracy and error from experimental methods are studied in this paper. The F.E.M., impulse tests and exciter tests are performed for the general simple structure whose exact solution can be obtained. So that the parameter and dynamic compliance can be got. From the result, the variation of natural frequency can be verified from the static preload. Further more the relationship of identify and difference for compliance and direction is presented in the exciting direction and measurement direction.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.2
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• pp.311-317
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• 2010

This paper deals with operation characteristics of a written-pole motor (WPM), having that of a permanent magnet (PM) synchronous motor and induction motor at once. The WPM also has a magnet layer on the surface of the rotor and the exciter pole that is a device to make the magnet layer magnetized during the operation. This study, introducing a fundamental structure and operation characteristics of a single-phase WPM, proposes a initial design method. With those ground, a 130W, single-phase WPM that is designed for a home appliance is presented and verified with a performance through the experiment.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.727-730
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• 1996

This paper presents a new on-line generator simulator which can be utilized for the control parameter setting of the exciter and the power system stabilizer (PSS). The proposed simulator equipped with A/D and D/A channels through which actual exciter and PSS can be connected. System parameters and disturbance sequence are easily programmed using friendly developed interface. The developed simulator is tested and verified by connecting a simple AVR implemented by op-amps.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.585-588
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• 2013

Electric motor with reduction gear systems are being adopted recently as main propulsion on the special-purposed ships. These specialized ships or offshore vessels require higher power rating generators for propulsion and accommodation power supply. This study investigated the cause of exciter components failure in the view of excessive vibration, force or abnormal ship motion in service. Countermeasures are proposed to address the exciter component failure. A 1.4 MW class dual-fuel engine generator using rigid foundation for a LNG carrier was used as research model.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1999.11a
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• pp.117-138
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• 1999

.8-VSB Modulator for Digital Television . ERRI'S ATSC VSB EXCITER . Pre-Corrector . Field Test . Lab Test