• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.65-67
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• 2001

PLC (Power Line Communication) is the communication method using the existing power line installed in houses and offices to convert and transmit high frequency communication signal from tens of KHz to tens of MHz, and receive the filtered signal using high frequency filter. The advantage of PLC is that PLC uses the existing power line installed in houses and offices so it does not require separate power line. Easy and convenient access using electric outlets is another advantage of PLC. However, PLC has some disadvantages such as limited transmission power, high load interference and noise, variable signal attenuation, characteristic of impedance selective possibility of frequency property. This study designed the boiler temperature control system by unit using the modem designed on the basis of technology used for PLC modem, and designed remote control system using internet. After conducting experiments with those two systems, it was possible to control stably. By commercializing this product, we can avoid unnecessary heating of separate temperature control unit, and save the cost according1y, and it is possible to control on a remote site using internet in a more convenient way.

• 융합신호처리학회논문지
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• 제15권1호
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• pp.15-22
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• 2014

본 논문에서는 '저탄소 녹색성장'의 세계적 추세에 따라 탄소 중립적 에너지원인 우드펠릿(wood pellet)을 사용하는 난방보일러 제어시스템 구현을 제시한다. 본 시스템은 공중전화망 및 이동통신망을 통해 원격으로도 제어 가능한 홈 네트워크 기반의 제어 및 관리시스템 구현도 포함한다. 구현된 시스템은 온도조절기능, 연료공급기능, 점화기능, 화력조절기능, 그을음제거기능 등을 수행하는 보일러 주제어부와 주제어부와의 RS-485 통신링크를 통해 각 방의 개별 온도를 제어 할 수 있는 온도조절기 모듈 및 보일러의 원격제어 및 모니터링이 가능한 공중전화망 및 이동통신망 인터페이스 부분으로 구성된다. 구현된 시스템은 기본동작시험과 원격제어시험을 통해 난방면적 $172m^2$에서 열효율 93.6%, 난방출력 20,640kcal/hr, 연료소모량 5.54kg/hr 으로 나타났다. 이러한 성능지표는 기존 개발된 펠릿보일러에 비해서 우수한 결과로써 기존 보일러에서는 적용하지 않았던 3단계의 점화과정과 그을음제거 기능과 함께 $C_dS$ 센서를 통한 불꽃감지기능 및 셔터개폐의 미세 조정을 통한 화력조절기능을 새롭게 적용한 결과이다.

• Journal of Biosystems Engineering
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• 제43권4호
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• pp.342-351
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• 2018

Purpose: Recently, an increasing number of farms have been cultivating shiitake mushrooms using a sawdust substrate and a cooler/heater. In this study, an attempt was made to develop an environmental control system using a heat pump for cultivating high-quality shiitake mushrooms. Methods: An environmental control system, consisting of an air-to-water type heat pump, a thermal storage tank, and a radiator in a variable opening chamber, was designed and fabricated. The system was also installed in the cultivation facility of a farm cultivating shiitake mushrooms so as to compare the proposed control system with a conventional environmental control system using a cooler-condensing unit and an electric hot water boiler. Results: The uniformity of the environment was analyzed through environment measurements taken at several positions inside the cultivation facility. It was determined that the developed environmental control system is able to control the variations in temperature and relative humidity to within 1% and 3%, respectively. In addition, a maximum temperature difference of $30^{\circ}C$ (maximum of $35^{\circ}C$, minimum of $5^{\circ}C$) and a maximum relative humidity difference of 30% (maximum of 90%, minimum of 60%) can be attained within 30 min inside the cultivation facility through the cooling of the heat pump and heating of the radiator in a variable opening chamber. Thus, the developed control system can be used to cultivate high-quality shiitake mushrooms more effectively than a conventional cooler and heater. Conclusions: In comparison with a conventional environmental control system, the developed system decreased the yield of ordinary mushrooms by 65%, and increased that of high-quality mushrooms by 217%. This corresponds to a 16% increase in gross farm income. Consequently, the developed system is expected to improve the income of shiitake mushroom cultivating farms.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1756-1760
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• 2004

Circulating Fluidized-Bed (CFB) boilers which have been operated in Korea were manufactured by the design technology of foreign leading companies. As they are not active to transfer their technology, domestic companies don't have the enough ability to design it independently yet. Doosan Heavy Industries & Construction Co. Ltd. and Korean Institute of Energy Research are trying to develop and improve the particle re-circulating device among the components of CFB boiler. Our purpose is to control the amount of particles leaving the re-circulating system by adjusting utility air and reuse the heat of circulating particles. The results of experiments with cold model system show that a fluidization state in the particle re-circulating device is very stable when the amount of utility air is supplied to its wind box with 2.29 times of minimum fluidization velocity. Also the amount of particles entering the riser don't increase linearly when the amount of utility air is supplied over 2.5 times of minimum fluidization velocity. Now we are testing its functional run with the hotstate experiment set-up.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1664_1665
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• 2009

Many years ago, most of thermal power plants built in this country were of subcritical pressure, of medium or small size, of constant pressure operations and of drum type steam generators with circulation type boilers. But, nowadays almost all of them were of high efficiency, of supercritical pressure, of big capacity, of sliding pressure operations, and of once through type steam generator. It has such advantage as the reduction of startup duration, but it control system and operation method are very complicated. It has a big difference in operation method of turbine and boiler. The feedforward control needs to be introduced to prevent such problems as thermal shock during the transit from normal operation into bypass operation. This paper introduces the turbine control and turbine bypass control during startup of thermal power plants.

• 대한기계학회논문집A
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• 제32권8호
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• pp.701-706
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• 2008

A continuous 3D tube bending machine has been developed for industrial boiler panel production. The machine consists of a main bender, a sub bender, a side bender, tube feeding rollers and control system that includes data management system. Tube position is controlled by a numerical control system. The bending former can be easily replaced according to the shape of bending form. Reduction of working time and improvement of production capacity from the practice have been achieved by bending a long tube in the machine developed.

• 대한환경공학회지
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• 제27권3호
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• pp.286-292
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• 2005

본 연구는 향후 산업적으로 질소산화물 규제가 중요한 문제로 대두될 만한 산업용 보일러를 대상으로 수행하였다. 일반적으로 SNCR 방법의 산업용 보일러로의 적용은 혼합을 위한 충분한 체류시간을 제공하지 못한다는 점에서 적합하지 않은 것으로 알려져 있다. 본 연구의 목적은 SNCR 장치의 산업용 보일러 적용가능성을 조사하기 위한 것이다. 구체적으로 연료로 중유를 사용하는 시간당 스팀 발생량 40톤 규모의 산업용 보일러를 연구 대상으로 하였다. 사업용 보일러의 수치 해석을 위한 3-D 직교좌표계 프로그램에는 난류 유동, 난류 연소반응, NOx의 생성과 환원제와의 반응을 통한 소멸반응 등을 포함하고 있다. 또한 개발된 코드에는 Lagrangian 방법에 의한 입자궤적 프로그램이 포함되어 있고, 주입구에서 접선방향으로의 선회효과를 계산에 의해 고려하였다. 선회버너 효과를 고려한 결과 단화염이 생성되었으며 NOx 환원반응에 적합한 온도 영역의 증가로 인해 NOx 제거효율도 향상되었다. 실험결과와의 비교를 통하여 프로그램을 검증하였으며, 계산결과 혼합용 공기 주입을 통한 환원제와의 혼합 향상을 통해서 SNCR 방법의 산업용 보일러 적용가능성을 확인하였다.

• 전자공학회논문지C
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• 제35C권8호
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• pp.68-74
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• 1998

The neural network predictiv econtroller (NNPC) is proposed for the attempt to mimic the function of brain that forecasts the future. It consists of two loops, one is for the prediction of output (NNP:neural network predictor) and the other one is for control the plant(NNC: neural network controller). The output of NNC makes the control input of plant, which is followed by the variation of both plant error and predictin error. The NNP forecasts the future output based upon the current control input and the estimated control output. The input and the output data of a system and a new method using evolution strategy are used to train the NNP. A two-step NNPC is applied to control the temeprature in boiler systems. It was compared with PI controller and auto-tuning PID controller. The computer simulaton and experimental results show that the proposed method has better performances than the other method.

• 대한전기학회논문지
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• 제36권3호
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• pp.221-227
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• 1987

Other problems associated with pole placement have been discussed. A simple algorithm for output feedback pole shifting has been developed. The algorithm is based on minimising an objective function which is the sum of the exponential of the real part of the system colsed loop eigenvalues. It is demonstrated that the algorithm is simple and effective in arriving at a suitable feedback matrix for the control of boiler using only two measurement.

• 제어로봇시스템학회논문지
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• 제12궈1호
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• pp.1-8
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• 2006

The home network system guarantees families a safe, economical, socially integrated and healthy life by using information appliances. And it provides a family with domestic safety, control of instruments, controllable energy and health monitoring by connecting to home appliances. This study designs the broadband PLC home controller using broadband PLC(Power Line Communication) technology which can save much cost at a network infrastructure by using the existing power line at home. The broadband PLC home controller consists of the broadband PLC module, the embedded main controller module and I/O module. The broadband PLC home controller can control various domestic appliances such as an auto door-lock, a boiler, an oven, etc., because it has various I/O specifications. In this study, selected home network middleware for the broadband PLC home controller is Jini surrogate using Jini technology designed by means of access to easily a home network system without a limitation of the devices. And a client application program is supported java servlet program to manage and monitor the broadband PLC home controller via web browser of a PC or a PDA, etc. Finally, for an application, we implemented and tested a home security system using one broadband PLC home controller.