• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1826-1827
• /
• 2011

발전소 제어시스템은 여러개의 제어루프가 있으면 이중 가장 중요한 것은 Unit master control(UMC)와 Boiler master control(BMC)이다. 전력거래소에서 발전기 출력 증발/감발 요구에 의해 가장먼저 BMC가 콘트롤 되어야 하고, 이어서 터빈 컨트롤이 추종하고 있기 때문이다. ABB P-14 제어시스템의 UMC의 각종기능과 구성에 대해 분석한 내용을 논하고자 한다.

• Journal of the KSME
• /
• v.20 no.2
• /
• pp.134-140
• /
• 1980

이미 주지하고 있는 모든 산업분야에서 자동제어를 채택하고 있는 근본 이유는 품질향상, 제품의 균일성향상, Energy 절약(효율향상), 원료절약, 설비이용향상, 인간의 단조로운 천업감소, (운전원의 효율성 증대) 때문이라고 요약 할 수 있다. 1910년경 Draft 및 급수제어 분야에서 부터 경제성 기술성 및 이용 요청에 따라 Boiler Control이 사용되어 왔으며 他 기술은 놀라울 정도로 발달한 반면, 이 분야는 변화가 거의 서서히 일어났다. 과거 50년 전부터 Boiler 자동제어기술은 관련 분야의 기술적 개발과 경제적 이유로 아래와 같이 여섯 단계의 발전과정을 거쳐 이제부터는 Digital 특히 Distributed Digital (기능 분산 형 System) 개발 및 산업적용에의 움직임이 활발할 것이다. 여기서 화력발전 Boiler 자동화의 어제와 오늘 그리고 내일에 대하여 소개하고자 한다.

• 제어로봇시스템학회:학술대회논문집
• /
• 1994.10a
• /
• pp.537-542
• /
• 1994

This paper gives a general survey of model-based fault detection and dignosis methods. Specific applications of these ideas to boiler systems will also be discussed. A novel aspect of the fault detection technique described here is that it explicitly accounts for the effects of using simplified models and errors from linearizing a nonlinear system at an operation point. Inclusion of these effects is shown to lead to novel fault detection procedures which outperform existing methods when applied to typical fault scenarios in boiler systems.

• Proceedings of the KIEE Conference
• /
• 1997.11a
• /
• pp.238-241
• /
• 1997

The recent trend toward increased use of the once-through supercritical boiler worldwide is mainly due to its rapid response. The transient behavior of the steam generator are essential in the study of the system performance of power plants as well as for the design of their appropriate control systems. In this paper, a mathmatical model of the once-through supercritical pressure boiler is obtained by simulating a set of nonlinear differential and algebraic equations.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.40 no.4
• /
• pp.263-273
• /
• 2016

The effect of recirculated exhaust gas on performance and exhaust emissions with FGR rate are investigated by using a natural circulation, pressurized draft and water tube boiler with FGR system operating at several boiler loads and over fire air damper openings. The purpose of this study is to apply the FGR system to a power plant boiler for reducing $NO_x$ emissions. To activate the combustion, the OFA with 0 to 20% is supplied into the flame. When the suction damper of two stage combustion system installed in the upper side of wind box is opened by handling the lever between $0^{\circ}$ and $90^{\circ}$, also, the combustion air supplied to burner is changed. It is found that the fuel consumption rate per evaporation rate did not show an obvious tendency to increase or decrease with rising the FGR rate, and $NO_x$ emissions at the same OFA damper opening are decreased, as FGR rates are elevated and boiler loads are dropped. While a trace amount of soot is emitted without regard to the operation conditions of boiler load, OFA damper opening and FGR rate, because soot emissions are eliminated by the electrostatic precipitator with a collecting efficiency of 86.7%.

• Journal of the Korean Society of Combustion
• /
• v.18 no.4
• /
• pp.1-11
• /
• 2013

The oxy-fuel combustion is $CO_2$ capture technology that uses mixture of pure $O_2$ and recirculated exhaust as oxidizer. Currently some Oxy-fuel power plants demonstration project is underway in worldwide. Meanwhile research project for converting 125 MWe Young-Dong power plant to 100 MWe oxy-fuel power plants is progress. In this paper, 1 D process analytical approach was applied for conducting process design and operating parameters sensitivity analysis for oxy-fuel combustion of Young-Dong power plant. As a result, appropriate gas recirculation rates was 74.3% that in order to maintain normal rating superheater, reheater steam temperature and boiler heat transfer patterns. And boiler efficiency 85.0%, CPU inlet $CO_2$ mole concentration 71.34% was predicted for retrofitted boiler. The oxygen concentration in the secondary recycle gas is predicted as 27.1%. Meanwhile the oxygen concentration 22.4% and moisture concentration 5.3% predicted for primary recycle gas. As the primary and secondary gas recirculation increases, then heat absorption of the reheater is tends to increases whereas superheater side is decreased, and also the efficiency is tends to decrease, according to results of sensitivity analysis for operating parameters. In addition, the ambient air ingression have a tendency to lead to decline of efficiency for boiler as well as decline of $CO_2$ purity of CPU inlet.

• Journal of the Korean Society of Combustion
• /
• v.15 no.1
• /
• pp.43-49
• /
• 2010

Co-combustion of syngas in an existing boiler can be one of the options for replacing conventional fossil fuel with alternative fuels such as waste and biomass. This study is aimed to investigate effects of syngas cocombustion on combustion characteristics and boiler efficiency. An experimental study was performed for a pilot-scale furnace with 4 oil burners. Tests were conducted with mixture-gas as a co-combustion fuel and heavy oil as a main fuel. The mixture-gas was composed of 15% CO, 7% $H_2$, 3% $CH_4$ and 75% $N_2$ for simulating syngas from air-blown gasification. And LHV of the mixture-gas was 890 kcal/$Nm^3$. Temperature distribution in the furnace and flue gas composition were measured for various heat replacement ratio by the mixture gas. Heat loss through the wall was also carried out through heat & mass balance calculation, in order to obtain informations related to boiler efficiency. Experimental results show that similar temperature distribution and flue gas composition can be obtained for the range of 0~20% heat replacement by syngas. NOx concentration is slightly decreased for higher heat replacement by the syngas because fuel NOx is decreased in the case. Meanwhile, heat loss is a bit decreased for higher heat replacement by the syngas, which implies that boiler efficiency can be a bit decreased when syngas co-combustion is applied to a boiler.

• Journal of Applied Reliability
• /
• v.12 no.1
• /
• pp.35-46
• /
• 2012

Wood pellet is one of biomass energy fuels, which is produced by compressing woody biomass such as sawdust, planer shavings, and whole-tree removal or tree tops and branches leftover after logging into cylindrical form. Latterly much attention has been paid to wood pellet boiler which is suitable for use at various scales in domestic and industrial furnaces for heat production to replace conventional fossil fuel energy sources since the use of wood pellet that is carbon neutral can alleviate global warming. This study presents the result of developing a high efficiency wood pellet boiler with 55MJ/h capacity. Efficiency has been improved by using a rotating disk burner with a shorter screw feeder. Special attention has been paid to the improvement of the safety of the wood pellet boiler from backfire by adopting a double protecting system composed of a shutter and an air curtain. The result shows that the efficiencies of the wood pellet boiler are 97.2% and 89.2% based on lower and higher heating values, respectively, at 15.1kW of heating output.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.18 no.6
• /
• pp.213-219
• /
• 2004

This paper describes the developmnet of a web-based boiler controller which can be in parallel operated with an existing boiler controller. The web-based boiler controller mainly consists of RTL8019AS NIC and TS80C32 microcontroller. In order to communicate over the Internet, we need to develop network driver, IP, TCP, UDP, ICMP, and HTTP. For a specific application like web-boiler controller, we have proposed a common global data buffer algorithm to minimize the RAM memory usage. Finally, the correctness and performance of the protocols are tested and verified using CommView and Dummynet. The development is satisfactorily operated only for few hundreds of bytes of RAM usage without sacrificing interoperability between hosts.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10a
• /
• pp.283-286
• /
• 1996

This study suggests a new methodology for the fault diagnosis based on the signed digraph in developing the fault diagnosis system of a boiler plant. The suggested methodology uses the new model, fault-effect tree. The SDG has the advantage, which is simple and graphical to represent the causal relationship between process variables, and therefore is easy to understand. However, it cannot handle the broken path cases arisen from data uncertainty as it assumes consistent path. The FET is based on the SDG to utilize the advantages of the SDG, and also covers the above problem. The proposed FET model is constructed by clustering of measured variables, decomposing knowledge base and searching the fault propagation path from the possible faults. The search is performed automatically. The fault diagnosis system for a boiler plant, ENDS was constructed using the expert system shell G2 and the advantages of the presented method were confirmed through case studies.