• 전력전자학회논문지
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• 제1권1호
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• pp.47-55
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• 1996

A new generator excitation system using a boost-buck chopper as a kind of static exciters is proposed to overcome the lack of field forcing capability of the bus fed exciter under the input line fault condition. It increases or maintains the generator field current by boosting the field voltage in the case of the input AC line voltage drop during and immediately after a fault. The validity of the proposed excitation system is verified with the computer simulation. The generator stability according to the each difference exciter is tested using a commercial software package-CYME. The simulation results of the stability analysis on the generator with the proposed exciter is better than that of the bus fed exciter. This boost-buck chopper exciter can be simply implemented and controlled by the modern power electronics technology.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.989-990
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• 2007

The excitation system of 500 MVA short-circuit generator is very important because of operation of various condition, for example, (over) load switching, short-time withstand current, short-circuit making and breaking current, etc. This paper introduces a feature of excitation system of 500MVA short-circuit generator and the function and construction.

• Journal of the Optical Society of Korea
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• 제17권1호
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• pp.81-85
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• 2013

A miniaturized fluorescence detection system based on total internal reflection (TIR) configuration, which is applicable to detecting the presence of biological materials labeled with fluorescence dye in micro total analysis systems (${\mu}TAS$), is proposed. In conventional fluorescence testing and analysis devices, interference between the excitation light beam and the emitted light from dyes is unavoidable. This paper presents a fluorescence detection system based on TIR configuration that allows the excitation light beam and the emitted light to be spatially perpendicular to each other so as to minimize the interference where fluorescence emission is detected at the orthogonal angle to the excitation beam. We achieved the limit of detection of about 5 nmol/L with a high linearity of 0.994 over a wide range of 6-FAM mol concentration, being comparable to that in earlier studies.

• 한국정밀공학회지
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• 제14권2호
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• pp.152-159
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• 1997

The asymptotic convergence of a coupled dynamic system, which is motivated from infinite dimensional adaptive systems, is investigated. The convergence analysis is formulated in abstract Banch spaces and is shown to applicable to a broad class of infinite dimensional systems including adaptive identification and adaptive control. Particularly it is shown that if a uniquely existing solution is p-th power integrable, then the solution converges to zero asymptotically. The persistence of excitation(PE) of a signal which arises in an infinite dimensional adaptive system is investigated. The PE property is not completely known yet for infinite dimensional adaptive systems, however it should be investigated in relation to spatial variable, boundary conditions as well as time variable.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.498-501
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• 2005

This paper deals with the design and evaluation of the robust controller for a synchronous generator excitation system to improve the steady state and transient stability. The nonlinear characteristics of the system is treated as model uncertainties, and then the robust control techniques are introduced into the power system stability design to take into account these uncertainties at the controller design stage. The performance of the designed controller is examined by extensive non-linear time domain simulation. It is shown that the performance of the robust controller is superior to that of the conventional PI controller. This paper also proposes an improved digital exciter control system for a synchronized generator using a digitally designed controller with database. Results show that the proposed control system manifests excellent control performance compared to existing control systems. It has also been confirmed that it is easy for the proposed control system to implement digital control.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제5권1호
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• pp.83-87
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• 2005

This paper deals with the design and evaluation of the robust controller for a synchronous generator excitation system to improve the steady state and transient stability. The nonlinear characteristics of the system is treated as model uncertainties, and then the robust control techniques are introduced into the power system stability design to take into account these uncertainties at the controller design stage. The performance of the designed controller is examined by extensive non-linear time domain simulation. It is shown that the performance of the robust controller is superior to that of the conventional PI controller. This paper also proposes an improved digital exciter control system for a synchronized generator using a digitally designed controller with database. Results show that the proposed control system manifests excellent control performance compared to existing control systems. It has also been confirmed that it is easy for the proposed control system to implement digital control.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1018-1020
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• 2002

For the life extension of the aged pumped storage power plant, the static digital excitation system had been developed by KEPRI(Korea Electric Power Research Institute). This paper will discuss the control design conception of pumping mode and the application results of system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1012-1014
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• 2002

This paper shows that a static redundancy excitation system for thermal power plant. The detailed contents are system explanation and MMI(Man-Machine Interface) integration, operation mimic graph.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.216-220
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• 1989

Direct calculation algorithm for the elements of A matrix is suggested for a single machine connected to the infinite bus. Excitation system and power system stabilizer are included. When A matrix is partitioned into seven submatrices, we can identify the location of non-zero elements and formula for each element. No matrix inversion and multiplication are necessary.

• 전기학회논문지P
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• 제54권4호
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• pp.211-216
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• 2005

In this paper a robust controller using adaptive backstepping technique is proposed to control the speed of wind power generation system. To make wind power generation truly cost effective and reliable, advanced and robust control algorithms are derived to on-line adjust the excitation winding voltage of the generator based on both mechanical and electrical dynamics. This method is shown to be able to achieve smooth and asymptotic rotor speed tracking, as justified by analysis and computer simulation.