• Journal of Energy Engineering
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• v.9 no.1
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• pp.10-18
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• 2000

기존 화력발전소에 탈황설비가 추가되고, 이로 인하여 새로운 계통의 통풍저항을 상쇄시키기위하여 기존의 유인통풍기와 탈황설비 사이에 승압통풍기가 설치되고 있다 통풍저항의 증가와 새로운 통풍기의 추가는 기존 통풍특성의 변화를 나타낼것이고 , 빈번한 발저소 정지를 가져오는 심한 노내 압력변동을 보이게 될 것이다. 따라서 , 발전소를 안전하게 운전하기 위해서는 설계된 통풍계통을 기반으로 한 교정된 운전모드에 관한 지식이 요구된다. 본 논문에서는 MMS (Modular Modeling System) 소프트웨어를 사용하여 우회 댐퍼의 개방을 수반하는 유인 및 승압통풍기의 비상정지의 사례에 따른 화력발전소 노내 압력, 통풍기의 압력과 유량, 댐퍼의 개도등과 같은 해석결과를 제시하고 논의하고 있다.

• Plant Journal
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• v.14 no.2
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• pp.39-44
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• 2018

In this study, I analyzed the effects on stabilizing the draft system, boiler efficiency when changing excess air ratio under 870 MW load limit operation condition in a large capacity coal fired power plant and decided optimum excess air ratio. It is positively necessary to choose adequate excess air ratio for stabilizing draft system because air pre-heater pressure drop and induced draft fan first stall margin are changing when adjusting excess air ratio. This study therefore, measured air pre-heater pressure drop, induced draft fan first stall margin, boiler efficiency, loss and has chosen adequate excess air ratio adjusting excess air ratio from 1.153 to 1.127. So it is recommended that the operation point needs to be changed to 1.127 that is not only to decrease air pre-heater pressure drop and to stabilize draft system and to secure stall margin but also to maintain boiler efficiency to equivalent level.

• Journal of Power System Engineering
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• v.13 no.6
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• pp.88-94
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• 2009

In this paper, vibration characteristics after applying variable speed control to fans with a rated speed used in a power plant are studied by performing experiments and analyzing finite element models. Then the campbell diagram is presented to verify the reason of the abnormal vibration measured from fan structure during variable operation of Forced Draft Fan & Induced Draft Fan. According to results, it is found that amplitude of acceleration increases abruptly when a 2X harmonic component meets the natural frequency of fan rotor. Therefore it is very important thing that investigate exactly dynamic characteristics for the rotor at variable speed zone before applying variable speed control to a rotor with a rated speed.

• Journal of Power System Engineering
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• v.14 no.5
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• pp.30-35
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• 2010

Recently, the large capacity draft fans in power plants had been changed to variable speed type to educe the power consumption. But the fan experienced the unexpected vibration at specific speed regions. In this study, the high vibration frequency of the fan was confirmed and the natural frequency of the rotor were measured and analyzed by FEM programs. It was analyzed that the vibration was caused by the resonance at the frequency, 30.7Hz. So, the rotor vibration characteristic was changed by adjusting the distance between the shaft bearings. It was conformed the high vibration was disappeared over the all operation speeds.