Abstracts

Abstracts

Abstracts

s

2017-04-01 Busbar abnormal great number detection method based on virtual difference current technology

TANG Zhiguo,ZHOU Xiaobo,CHEN Qi,WANG Yongxu,CHEN Hongyan(Nanjing Guodian Nanzi Power Grid Automation Company Limited, Nanjing 211153, China)

Abstract:With the application of intelligent substation and localized protection, the probability of sampling abnormal great number is increasing. This required higher reliability of busbar protection. This paper introduced a new approach to recognize abnormal sampling. By linear interpolation, the virtual busbar protection difference current could be calculated. To compare actual and calculated difference current, fault and abnormal great number could be accurately distinguished. This method was approved by simulation, and is able to effectively eliminate the effect of sampling abnormal great number on busbar protection, and increase busbar protection reliability.

busbar differential protection; abnormal great number; virtual difference current; linear interpolation; difference coefficient

2017-04-04 Features and mechanism of interturn short circuit fault by energizing no-load transformer

GUO Xiao, XING Wu, HU Bing, WANG Zhe(Nanjing SAC Automation Company Limited, Nanjing 211151, China)

Abstract:When interturn short circuit fault by energizing no-load transformer occurs, the three-phase current differential protection is blocked by blocking criteria, and it causes the single-phase interturn short circuit fault could not be rapidly removed, which threats the safe operation of transformer. Through establishing the equivalent model of interturn short circuit fault, this paper deduced the analytical expression of magnetic flux of exciting windings and analyzed the influences of system impedance and number of faulted turns on fault features. It concluded that the larger system impedance and number of faulted turns, the more difficult the inrush current occurs. Using the PSCAD software, the correctness of the conclusion was verified, and it provided a theoretical basis for the selection of blocking criteria and blocking schemes of differential protection.

Keywords:interturn short circuit；inrush current；system impedance；PSCAD software

2017-04-08 A study of differential protection of variable-frequency motor and its applications

ZHANG Yanlin1, WANG Peng1, HAN Yingjie2, FAN Yusheng3, LIU Zheng4(1.Technical Information Center,Henan Company of State Power Investment Corporation,Zhengzhou 450000, China; 2.Henan Company of State Power Investment Corporation,Zhengzhou 450000, China; 3.Kaifeng Branch, Henan Company of State Power Investment Corporation，Kaifeng 475000, China; 4.Jiangsu Wiscom Technology Company Limited，Nanjing 211100，China)

Abstract:As the application of frequency converter in auxiliary power, the requirements of frequency conversion transformation of high-voltage motors and variable frequency differential protection are increasing. Taking the frequency conversion transformation of condensate pump motor as an example，this paper introduced the transformation scheme of differential protection and the non-power frequency tracking sampling value differential algorithm it adopted, and verified its sampling performance and protection reliability by experiments, which provided a reference for the differential protection transformation of a high-voltage variable-frequency motor.

Keywords:high-voltage motor；frequency converter; frequency tracking; sampling value differential protection

2017-04-11 Coal-fired boiler performance test points installation standardization study

LI Guangwei(China Power Huachuang Electric Power Technology Institute Company Limited, Shanghai 200086, China)

Abstract:The standardization installation of test points impacted the accuracy of thermal power plant unit boiler performance test. This paper summarized the experience of boiler performance tests, discussed installation standardization and methods to enhance the test accuracy of flue gas ingredient, ash, temperature, pressure, flow rate and other parameters. This provided solid foundation for energy saving and environmental protection.

Keywords:coal-fired boiler；performance test；test point；installation；standardization

2017-04-15 Simulation study of fan blade shimmy control to reduce wind turbine fault rate

ZHAN Peng, GUO Jinxue, CHEN Xiaoming(China Huadian Engineering Company Limited, Beijing 100160, China)

Abstract:Wind power industry has been rapidly increasing in recent years. With the warranty of wind turbine expired, operation maintenance is critical, especially the fan blade shimmy was already one of the main causes of wind turbine unit failure. To solve the problem of fan blade shimmy, minimum and maximum linear quadratic Guass optimal control theory was indicated. This method using Eulerian-Lagrange equation of the vibration of the fan blade system mathematical model is established, and the minimum and maximum LQG controller scheme design. The simulation results show that the controller has good control effect to blade shimmy, reach the wind generator to reduce failure rate, to enhance the efficiency of the wind power generating units.

Keywords:wind turbine unit; fan blade; shimmy; fault rate; simulation study

2017-04-19 Heat supply unit on-line monitoring method study and application

MA Pengbo1, JIA Peng1, WANG Fengxian2, ZHANG Zhao1, WANG Bo1, LIU Fusheng1, XIE Mingming1(1.Xi’an Xire Power Plant Information Technology Company Limited, Xi’an 710054, China; 2. Xi’an Xire Power Plant Chemical Technology Company Limited, Xi’an 710054, China)

Abstract:This paper introduced the system composition of thermal power heat supply unit, heater supply unit monitoring method and coal consumption on-line calculation method. On-line monitoring calculating methods of thermal power plant heat supply unit steam extraction, heat exchange station, water pipeline and heat supply system was analyzed. The accuracy of a super-critical unit generating coal consumption on-line calculating sys-tem was verified. Combined with on-line monitoring data, pro-vided by a power group, authors determined that heat supply unit on-line monitoring system is able to satisfy the requirement of power generation dispatching, economical analysis and heat supply system monitoring.

Keywords:heat supply unit; coal consumption calculation; power generation dispatching; heat supply system; heat exchange station; on-line monitoring

2017-04-24 Corrosion leakage mechanism analysis of super heater tubes for refuse incineration power plant

LI Li1，SONG Jinghui2(1.Guangdong Clean Environmental Protection Technology Company Limited, Guangzhou 510075, China; 2.Electric Power Research Institute of Guangdong Power Grid Company Limited, Guangzhou 510080, China)

Abstract:In order to solve the frequently occurred leakage problem of super heater in the actual production process of refuse incinerator, this paper conducted a comprehensive analysis of the corroded tube of a certain refuse incineration power plant using the scanning electron microscope with energy disperse spectroscopy (SEM-EDS), ion chromatograph (IC), X-ray fluorescence (XRF) and X-ray diffraction (XRD), discussed its corrosion mechanism, and proposed some suggestions on how to prevent the corrosion leakage of super heater. The study shows that gaseous chlorine corrosion and alkali metal ash deposit corrosion are the root causes of corrosion leakage of super heater tubes. For gaseous chlorine corrosion, the HCl and Cl2produced by refuse incineration could spread to the metal lining of tube wall and corrode it under oxidizing atmosphere, and together with the SO2in flue gas, the synergistic effect would accelerate the corrosion and form some corrosion pits, which may lead to a leakage eventually. For alkali metal ash deposit corrosion, the alkali metal compound produced by refuse incineration deposits at the outside of tube wall, and the SO2in flue gas could react with alkali metal compounds to form alkali metal sulfates, which could corrode the tube wall under oxidizing atmosphere. Besides, part of the alkali metal chlorides in ash deposition could corrode the ferruginous oxide film under oxidizing atmosphere, which also could accelerate the corrosion of tube wall.

Keywords:refuse incinerator; super heater tube; corrosion mechanism; leakage

2017-04-28 Practice of noise reduction transformation for a heat recovery boiler in gas power plant

YU Weigen，YAO Yong(Shanghai Fengxian Gas Turbine Power Generation Company Limited, Shanghai 201403, China)

Abstract:For a vertical heat recovery boiler in a certain gas turbine power plant, it has problems of big noise and prominent low-frequency noise, and because of its compact arrangement, the conventional measure of overall sound insulation enclosure could not be implemented. This paper studied the low-frequency noise of boiler of this type, identified its source, developed a new noise reduction device according to the analysis result, and applied it in practice. The application result shows that the device could significantly reduce the low-frequency noise of boiler and improve the surrounding noise environment.

Keywords:gas turbine power plant；heat recovery boiler; low-frequency noise; ETS; upgrade

2017-04-30 600 MW supercritical unit interconnection control valve fully-opened incident analysis and treatment

WU Xueli1，WANG Weitao2(1.Hubei Huadian Xiangyang Power Plant Company Limited, Xiangyang 441000, China; 2.Hubei Electric Power Research Institute, Wuhan 430077, China)

Abstract:This paper took Hubei Huadian Xiangyang Power Plant Company Limited MAXDNA control system digital electric hydraulic (DEH) as study objective, summarized the incident of control valve fully-opened by mistake while synchronization. Rapid treatment measures were indicated. Which could be referred to treat similar incident.

Keywords:DEH; interconnection; control valve fully-opened; control system

2017-04-32 Application analysis of silicon carbide ceramics in boiler turbulent combustor

LI Zhigang, WANG Lei(Chaoyang Yanshanhu Power Plant Limited, Chaoyang 122004, China)

Abstract:The problem of abrasion is existing in large scale power plant boiler combustor operation. This problem changed the air distribution, increased the adjustment difficulty of burning process, increased the primary-air flow rate, and ultimately increased the NOxdensity. By analyzing the causes of combustor abrasion, and comparing the application condition of aluminum oxide ceramics and silicon carbide ceramics, to use silicon carbide ceramics as anti-abrasion material is able to solve the problem of anti-corrosion liner detachment and combustor abrasion.

Keywords:power plant; boiler; combustor; abrasion; silicon carbide ceramics; turbulent combustor

2017-04-34 Analysis of ETS reform of Luohe Power Plant

WANG Hao, WU Hao(Huadian Luohe Power Plant Company Limited, Luohe 462000, China)

Abstract:This paper introduced Huadian Luohe Power Plant Company Limited steam turbine emergency trip system (ETS) improvement reconstruction. Based on the control philosophy, original PLC control system was instead by General Electric Energy Group Xinhua Control Engineering Company Limited’s OC6000e system, and integrated into decentralized control system (DCS) network.Control-display integration was realized. Reliability and expandability of ETS was significantly improved.

Keywords:ETS; DCS; upgrade; improvement

2017-04-36 Control optimization and improvement of 600 MW unit soot blowing system

CHEN Feng(Huadian International Company Zouxian Power Plant, Zoucheng 273522, China)

Abstract:By analyzing multiple fault incidents of a subcritical boiler soot blower, blower control circuit and logic improvement plan was indicated. After improvement, blower is able to warn operator to avoid accident caused by boiler pipeline explosion. At the same time, by innovating and improving the transmission system, the problem of blower frequently failed was solved.

Keywords:soot blower; series connection; improvement；interlock

Abstracts

2017-04-38 High sulfur anthracite super-critical W-flame boiler movable blade adjustable axial induced fan bladejam and draft prevention and treatment

ZHUO Renchun(Guizhou Huadian Tongzi Power Plant Company Limited, Zunyi 563200, China)

Abstract:For super-critical W-flame boiler that firing high sulfur anthracite, the axial induced fan blade jam and shift is an existing problem. After analyzing this problem, a series prevention and treating measures was indicated. This problem was effectively controlled.

Keywords:high sulfur anthracite; W-flame boiler; induced fan; blade jam and shift

2017-04-40 660 MW unit blended-combustion inferior coal adjusting analysis

KUANG Zheng, KONG Fanxu，GUO Yiyong(Anhui Huadian Lu’an Power Plant Company Limited, Lu’an 237126, China)

Abstract:Due to serious competition, more and more large capacity power plants prefer to blended-combustion inferior coal for lower cost. During blended-combustion, the operation safety, load and pressure shall be ensured to avoid coal-water unbalance. This paper discussed the assurance measurements, especially the operation safety while peak load and underload.

Keywords:inferior coal; blended-combustion; combustion; adjusting

2017-04-42 Economical analysis of gas boiler exhaust steam exhaust

TANG Mingfeng, WU Minjie(Hangzhou Huadian Xiasha Thermal Power Company Limited, Hangzhou 310018, China)

Abstract:In order to improve the economic operation of the gas boiler deaerator, by adjusting the deaerator steam heating mode and regulation mechanism, thereby effectively reducing the exhaust loss of the deaerator, greatly saves the operation cost. After optimization, the deaerator exhaust loss is reduced, Operational cost on gas reduced 730 000 yuan per year.

Keywords:gas-fired boiler; deaerator; stream exhaust loss; economy

2017-04-44 Analysis of 4～20 mA redundant current output in DCS

WU Shenghua, TIAN Haibo(Nanjing Guodian Nanzi Valmet Automation Company Limited, Nanjing 210032, China)

Abstract:Introduces the distributed control system (DCS) 4～20 mA current output circuit principle, on the basis of the introduced three kinds of the realization of 4～20 mA current redundant output method, according to their respective advantages and disadvantages are analyzed.

Keywords:industrial control; distributed control system; redundant

2017-04-46 Reason analyses and treatments of the derailing problem of main harrow tensioning wheel and the unsoldering problem of oil cylinder base of a reclaimer

YANG Gongxiao, MA Qian(Huadian Zhengzhou Mechanical Design Institute Company Limited, Zhengzhou 450015,China)

Abstract:A reclaimer in strip material yard is a type of environmentally friendly large mechanical equipment and the tensioning condition of chains would directly influence its normal operation. According to the calculation formulas of pretightening force and minimum pretightening force, the type selection of tension cylinder could be conducted, including the appropriate cylinder diameter and cylinder pressure. Through analyzing, this paper considered that the main reason of the derailing problem of main harrow tensioning wheel and the unsoldering problem of oil cylinder base is misoperation. After that, this paper provided corresponding solutions for the above problems.

Keywords:reclaimer; chain wheel tensioning; chain; pretightening force; cylinder base; unsoldering

2017-04-48 600 MW unit high pressure reheater start-up pipeline vibration analysis and treatment

HUANG Xiaojun(Hunan Huadian Changsha Power Generation Company Limited, Changsha 410203, China)

Abstract:To save start-up energy and shorten boiler start-up time, high pressure reheater was put into operation in advance in start-up stage. Due to small water flow and full cold state, dewater pipeline usually serious vibrates during start-up. After analyzing vibration causes, technical improvement was carried out accordingly. Vibration of high pressure reheater in start-up stage was eliminated.

Keywords:boiler start-up；high pressure reheater；pipeline vibration

2017-04-50 Reason analysis of high exhausted gas temperature of a boiler and its countermeasures

WANG Donghui(Baiyinhua Jinshan Power Generation Company Limited, Xilingol 026200，China)

Abstract:The change of exhausted gas temperature has a great influence on boiler efficiency. After the 600 MW direct air-cooled lignite-fired subcritical unit of Baiyinhua Jinshan Power Generation Company Limited put into operation, there exist a problem of high exhausted gas temperature. This paper deeply analyzed the main reason of high exhausted gas temperature, and adopted some measures, such as adjusting oxygen volume, optimizing coal pulverizing system and adjusting combustion, etc. Then it conducted a technical transformation of economizer. After the transformation, the exhausted gas temperature reached the design value basically.

Keywords:boiler; exhausted gas temperature; boiler efficiency; operation optimization；technical transformation

2017-04-56 600 MW unit flue gas waste heat ladder-form utilization energy saving effects comparison

HAN Xianfei1, ZENG Hao2, ZENG Yujuan2, BAI Jinde3, SUN Huailin2(1.Guodian Duyun Power Plant Company Limited, Qiannan 550500, China; 2.Guangdong Energy Saving and Environment Protection Company Limited, Dongguan 523073, China; 3.State Nuclear Electric Power Planning Design & Research Institute Company Limited, Beijing 100095，China)

Abstracts

Abstract:With the development of coal-fired power plant flue gas waste heat recovery technology, flue gas temperature of low temperature economizer is limited to 130～150 ℃. According to the level of flue gas heat step utilization using principle, operation data of 600 MW unit of Guodian Duyun Power Plant Company Limited of the existing scheme combined process of medium temperature economizer of low temperature economizer the preliminary design, based on the equivalent enthalpy drop method of traditional economic calculation, the results show that the technology of the energy saving effect is remarkable.

Keywords:flue gas waste heat;step utilization; economizer

2017-04-60 600 MW super-critical unit water consumption reduction reconstruction practice

WU Xiaohui(Hunan Huadian Changsha Power Plant Company Limited, Changsha 410203，China)

Abstract:This paper introduced the condition of the super-critical unit of Huadian Changsha Power Plant. A series of reconstruction plan which included water purification, desalination and water consumption reduction of precision processing system was indicated. This paper introduces the implementation process and analyzes the effect and the corresponding economic benefits.After implementation, good results have been achieved. The scheme is to provide reference for the corresponding transformation of the same type of power plant.

Keywords:supercritical unit；water consumption reduction; reconstruction; economic efficiency ;settling pond

2017-04-63 HG-1025/17.45-YM28 sub-critical boiler ultra-low emission improvement

YANG Xuhao

(Huadian Energy Company Limited Mudanjiang Second Power Plant, Mudanjiang 157015, China)

Abstract:Per national environmental protection requirements, ultra-low emission improvement of Huadian Energy Company Limited Mudanjiang Second Power Plant was carried out.This paper briefly introduced the improvement of desulfurization, denitration and dust removal system. After improvement, unit pollutant density was significantly reduced. Beside environmental achievement, corporation benefits were increased by environmental protection price. This paper also indicated specific treatment for the booster fan over-flow after improvement.

Keywords:desulfurization；denitration；dust removal；environmental protection；ultra-low emission improvement

2017-04-66 Influence of denitration transformation on air preheater of supercritical unit and its countermeasures

XU Qi, PAN Mengmeng, LI Qiaoqiao(North China University of Water Resources and Electric Power School of Electric Power, Zhengzhou 450045, China)

Abstract:Taking the denitration transformation of No.4 supercritical unit of a certain power plant in China as an example, this paper analyzed the influence of denitration transformation on air preheater, proposed some feasible countermeasures for the problems, and provided some reasonable experience for the future denitration transformations of similar coal-fired power units.

Keywords:supercritical unit; denitration device; air preheater

2017-04-68 A comparative analysis of mixed burning cost of lignite

ZHANG Fang, FANG Jin, ZHOU Jiang(Fujian Huadian Kemen Power Generation Company Limited, Fuzhou 350500, China)

Abstract:Through calculating the calorific value loss in the storage period of lignite and the coal consumption loss in the mixed burning process, this paper converted the pros and cons after mixed burning of lignite into purchase cost of standard coal and compared it with common bituminous coal. After that, it analyzed the profit boundary point of mixed burning lignite from an economic point of view.

Keywords:lignite; mixed burning; standard coal; calorific value loss; cost

2017-04-71 Wind turbine generator yawing correction analysis method study

ZHANG Wei, LEI Yang, ZHANG Zhongquan(Huadian Electric Power Research Institute，Hangzhou 310030，China)

Abstract:Yawing system is one of the key systems of wind turbine generator. The error of yawing system will affect the energy generated. A yawing correction analysis method based on operation data was indicated. This method is based on wind direction angle interval model, built on Betz’s law. By inputting the wind speed, wind angle, power rate, generator speed and other data collected by SCADA into this model, power rate curve will be calculated. After comparing and analyzing, the unit yawing error was indicated. This method was applied on a wind power plant in Yunnan Mengzi, and approved by comparing with airborne laser radar anemoscope.

Keywords:wind turbine generator；yawing system；yawing correction；wind angle；laser radar anemoscope

2017-04-74 Study on the selection method of direct normal irradiance design points for tower molten salt solar thermal power generation

GAO Song(Northeast China Power Engineering Company Limited of China Power Engineering Consulting Group Corporation, Changchun 130021, China)

Abstract:According to the technical features of tower solar thermal power generation, taking the 50 MW installation capacity as a computation model, and on the basis of solar energy resource conditions of a certain area, different direct normal irradiances (DNI) are chosen as the design points, and together with different solar multiples (SM) and thermal storage times, several allocation plans are formed. Taking the same annual utilization hours as boundary condition and taking the minimum unit price as optimization target, this paper simulated and filtered the allocation plans. The results shows that different annual power generating requirements need different allocation plans. Even in same area, different annual power generating capacities need different design points. The design points is a necessary condition to confirm the day lighting area at concentrated field under a certain SM, and through the optimization design of spotlight, heat absorption, heat storage and generating unit capacity, the day lighting area at concentrated field could be confirmed. At last, the confirmation of design point could provide a reference for the equipment selection in the design of spotlight and heat storage systems.

Keywords:tower solar thermal power generation; direct normal irradiance; solar multiple, thermal storage time; design point