2018-02-04Monitoringonlubricationconditionofwindpowergearboxanddevelopmentoffaultdiagnosissystem

YUNHongli,ZHANGTao,SONGXiaona(North China University of Water Resources and Electric Power, School of Mechanical Engineering, Zhengzhou 450046, China)

Abstract:Gearbox is the key subsystem of a wind power unit, and the intelligent control and management is a key to prolong service life of lubrication system. It forecasts lubrication monitoring parameters by taking the Grey theory, which achieves the real-time monitoring and prediction on gearbox lubrication condition. Fault tree model is used to diagnose the fault in lubricating system, which can improves the efficiency and accuracy of diagnosis.

Keywords:wind power gearbox; lubrication system; Grey theory; fault tree; condition monitor; condition diagnosis

2018-02-07Decentralizedcontrolandcentralizedmanagementofbio-gasgenerationprojectcontrolsystem

PANNing,CHENYi,LIUWei,ZHANGTingjun,MAZonghu(China Huadian Engineering Company Limited, Beijing 100160, China)

Abstract:At present, most bio-gas power stations follow the standards and control methods of thermal power plant for their plant control systems. The source of materials for thermal power plant is relatively stable, and the control requirements for units operation are quite strict. The configuration of the control system is designed according to the concept of “no stopping”. In the case of bio-gas power plant, if this method is continuously used to control, it will cause unnecessary waste and control irrationality. In this paper, according to the actual running situation of bio-gas power plant, it puts forward the control mode called “decentralized control, centralized management”. This mode takes the key consideration on balancing the coupling relationship between each unit in the procedure, which can optimize its running state and enhance the power generation efficiency.

Keywords:bio-gas generation; control system; centralized management; decentralized control

2018-02-10Causesandcontrolmethodsofcracksonmortarpadforsteamturbineinthecoldanddryenvironment

CHENChunhui，YAOZhiwei，DONGYi(China Energy Engineering Group Zhejiang Thermal Power Construction Company Limited, Hangzhou 310016, China)

Abstract:It compares the mortar pad defect of HP/IP bearing pedestal with that of LP cylinder under the dry-cold environment.The causes of crack defects were low environmental temperature, temperature disparity between day and night, and inadequate maintenance measures after pouring. It puts forwards improvement measures which are covering with electric blanket and quilt, setting up the wind tent, and controlling the time of maintenance. The crack of mortar pads is effectively controlled and the primary success rate of mortar pad making is improved.

Keywords:steam turbine; mortar pad; crack; dry-cold environment

2018-02-13Researchandapplicationofcombinedclosedashyardforlargeandmedium-sizedcoal-firedpowerplants

SUNJianchao(China Huadian Engineering Corporation Limited, Beijing 100160,China)

Abstract:Fly ash storage of large and medium sized thermal power plant is quite substantial. The traditional open-air yard is hard to meet the requirements of environmental protection, and conventional semi-closed storage yard to a certain extent reduces the comprehensive utilization value of dry ash.It proposes a scheme of combined closed ash yard which contains a large steel silo of fly ash and a steel arch-frame closed ash shed.Compared with the outdoor dry ash field solution, the scheme's captalized cost is low.The scheme can effectively solve the environmental pollution in the procedure of construction and operation of ash yard and significantly improve the level of the comprehensive utilization of fly ash. Its social benefit and economic benefit is remarkable.

Keywords:coal-fired power plant; fly ash; ash yard; steel silo; closed ash shed; dust pollution

2018-02-16Adetectionmethodabouttherotorovervoltageprotectiondevice

LIUYulin,ZHUHongwei,GUJianrong(Nanjing Guodian Nanzi Valmet Automation Company Limited, Nanjing 210032，China)

Abstract:To regularly detect the performance of generator rotor overvoltage protection device, a method of using the existing low voltage equipment in testing the actual operating value of rotor overvoltage protection is put forward: by measuring the operating voltage of the trigger, then the actual operating value of the rotor overvoltage protection device can be calculated. It is verified that the method of the test results agree with conventional methods. The operation is simple and there is no high voltage in the process. It can be used as a rapid detection method on the generator rotor overvoltage protection device to ensure the reliable operation of the generator.

Keywords:generator rotor; overvoltage protection; trigger

2018-02-19Detectionoftransmissionlineandtrackingmethodbasedonelectromagneticsensingarray

WUGuosong,NIHong,ZHAOHaili,CHENJing(State Grid Henan Electric Power Company, Xuchang Power Supply Company, Xuchang 461000, China)

Abstract:Addressing the need of identification, position measurement, obstacle avoidance and tracking in the process of unmanned aerial vehicle inspection, a detection and tracking meth-od for power-frequency transmission line and equipment is designed. The system includes passive array magnetic induction antenna device, array scanning and acquisition control circuit, attitude and distance data processor. The passive array magnetic induction antenna device is used as the magnetic field information detection and testing link. It is controlled by the scanning and acquisition control link to collect the magnetic field distribution and intensity information. Then, the follow-up data signal processing link can calculate the location, distance and other information of detected high-voltage transmission line. Finally, it is verified on the platform developed by the ARM series STM32F104 hard ware. Through the on-site flight test, the results turn out to be satisfying.

Keywords:patrol; magnetic induction array; scanning control; magnetic field distribution; attitude parameter

2018-02-21Reasonanalysisandpreventionoftheburnoutofboilerburnernozzle

LIGe1,ZHUHaibao1,WANGJun2(1.Huadian Electric Power Research Institute, Department of the Material Technology, Hangzhou 310030, China；2.Harbin Thermal Power Plant, Department of the Production Technology, Harbin 150046, China)

Abstract:Burnout on the boiler burner nozzle was observed in a power plant shortly after it start running for a short period. ash deposits, coking, bulge， and swelling were found on the water wall inside the hearth, which seriously affect the operation safety of the unit. In is paper, the quality of the firing coal, the structure of the burner, the method of combustion was studied as the influential factors, the exiting problems of the unit is summarized, and the suggest on the prevention of the burnout of the boiler burner nozzle is presented.

Keywords:boiler burner nozzle; burnout; water wall; reason analysis

2018-02-25Causesanalysisandtreatmentofendshieldoilleakin500kVmaintransformerbushing

YUWentao，HUANGWenfeng，MAXin(Anhui Huadian Wuhu Power Generation Company Limited，Wuhu 241080，China)

Abstract:A 500 kV main transformer of a power plant found oil leak defect at its bushing end shield of the high voltage side during overhaul. Through analysis, it was confirmed that the reason for oil leak was ungrounded end shield. It introduced the replacement of high voltage bushing and partial discharge test in details. After replacement, it was found that the end shied ground column was damaged during the dielectric dissipation test of transformer through disassembly check and the grounded copper sleeve was jammed and could not bounce fully. Countermeasure was carried out according to the causes of the defect.

Keywords:main transformer；bushing；end shield；oil leak；ground

2018-02-29Problemsandoptimizationofwaterringvacuumpumpinthermalpowerplant

ZONGXudong(Huadian Power International Corporation Limited Technology Service Center, Jinan 250014, China)

Abstract:It lists various problems of thermal power plant water ring vacuum pump, analyze the problem from principle, make economic and safety comparison with other optimization reform program of currently vacuum pump and draw up the optimal design and reform scheme.

Keywords:thermal power plant; water ring vacuum pump; power consumption rate; limit vacuum; pumping capacity

2018-02-32Analysisofthecausesandpreventivemeasuresofcondenserscalinginagasturbineplant

GAOQiangsheng(Zhejiang Energy Group Research Institute Company Limited, Hangzhou 311121, China)

Abstract:Taking an abnormal scaling issue of a condenser in gas turbine plant, the causes of scaling is analyzed, considering the condenser temperature control, corrosion inhibitor dosing control, circulating water concentration ratio and so on. Preventive measures are put forward to ensure the safe and economic operation of power generating units.

Keywords:gas turbine plant; condenser; scaling; scale inhibitor; concentration ratio; circulating water

2018-02-35Optimizationanalysisonoperationmodeofinduceddraftfanandboostfan

XUBing,SONGHongfei(Dandong Jinshan Thermoelectricity Company Limited, Dandong 118000, China)

Abstract:After the ultra-clean emission modification on two units in a power plant, the original operation characteristics of induced draft fan and boost fan are changed. After analyzing the operation characteristics of modified induced draft fan and boost fan, reasonable and economic operational mode can be found through comparing test results.

Keywords:induced draft fan; boost fan; energy conservation and emission reduction; ultra-clean emission; economic operation

2018-02-38Theproblemsandcountermeasuresofstart-upof600MWsupercriticalcoal-firedpowerunitwithsteamfeedpump

WANGJianghong,YEWenhua(Guangdong Zhuhai Jinwan Power Generation Company Limited, Zhuhai 519060, China)

Abstract:In recent years,600 MW supercritical coal-fired units used steam pumps to replace the electric pump in the water supply so as to excavate the potential of the unit. Taking Guangdong Zhuhai Jinwan Power Generation Company Limited as an example, this paper analyzed and summed up the problems encountered during the start-up of this mode, and put forward the countermeasures to provide a reference for the successful implementation of steam pump replacing the electric pump in the same type of units.

Keywords:supercritical unit; coal-fired unit; steam pump; electric pump; unit potential tapping; start-up problem; countermeasure

2018-02-40Applicationanalysisofbackwashmethodforlow-lowtemperatureeconomizerofsupercriticalunit

WEIDong(Huanggang Dabie Mountain Power Generation Company Limited, Macheng 438304,China)

Abstract:A low-low temperature economizer was installed in the#1 unit of Huanggang Dabie Mountain Power Generation Compa-ny Limited during its ultra-low emission modification which was carried out during A class maintenance. In the practical application, the thermal system of the low-low temperature economizer is restricted by the condenser water flow in both cold and hot condition, and cannot get high-flow flushing. During ultra-low emission modification in the A class maintenance of#2 unit，a backflush door was installed. Backflushing method is adopted to shorten the washing time and save a lot of desalination water. Therefore, it is a good chance to carry out backwashing modification on low-low temperature economizer during C class maintenance on#1 unit, which will achieve good results.

Keywords:supercritical unit; ultra-low emissions; economizer; high-flow flushing; backflush door; desalination water

2018-02-43Optimizationofmeasurementmethodfordisconnectorcircuitresistanceinstrongelectromagneticinterferenceenvironment

LIWeijiang,TANYinghui,LIGuangyuan,WANGQiang,MANing(Jibei Electric Power Maintenance Company, Beijing 102488, China)

Abstract:According to a disconnector circuit resistance test, electromagnetic environment of the test site is analyzed. By calculating the electromagnetic field in the test environment and the induced voltage in the test circuit, the electromagnetic interference has been proved to be an important reason for the distortion of the disconnector circuit resistance. By improving the wiring method of disconnector measuring circuit, the influence of electromagnetic interference on measuring the resistance of the disconnector is reduced. The measured value of disconnector circuit resistance is more accurate and reliable, which improves the accuracy while testing disconnector circuit resistance and the production efficiency during grid maintenance.

Keywords:substation; disconnector; electromagnetic interference; circuit resistance test

2018-02-46Discussionoveroilsamplingtechniqueusedinoil-immersedtransformerfilledwithnitrogen

WUXinjie(Ningbo Baoxin Stainless Steel Company Limited, Ningbo 315800, China)

Abstract:Common oil-immersed transformer is notfilled with nitrogen，and its oil sample technology is also relatively mature. However, the oil-immersed transformer filled within nitrogen is rarely introduced on papers. If conventional oil sampling technology is used, it is the external air that will be sucked into the inside of the nitrogen filled oil-immersed transformer frequently, rather than the oil sample that can be moved out of it. Through the discussion over oil sampling technology and combination with engineering practice, it summarizes an oil sampling technology that is suitable for nitrogen filled oil-immersed transformer and can solve the above problems well.

Keywords:transformer; nitrogen; oil-sampling

2018-02-48Applicationofignitingtheblendedcoalsbyhigh-powerplasmaignitiondevice

ZHANGHai1,QIUWangcheng2(1.Hubei Huadian Xiangyang Power Generation Company Limited, Xiangyang 441004, China；2.Wuhan Tianhe Technology Company Limited,Wuhan 430077, China)

Abstract:Taking the plasma ignition reform of unit 1 of Hubei Huadian Xiangyang Power Generation Company Limited. as an example, it introduces the contactless 300 kW plasma ignition system and its advantages in igniting mixed coal (50% meagre coal and 50% bituminous coal).And it analyzes the economic benefits and the social benefits that the plasma ignition system brings to the power plant.

Keywords:plasma; ignition system; contactless

2018-02-50Reasonanalysisandimprovementonthebladesfaultoftwo-stageadjustablemovingbladeaxialflowdraftfan

LIUEnsheng1,ZHOUXingang2(1.Huadian Power International Technical Service Center, Jinan 250014, China; 2.State Grid Shandong Electric Power Research Institute, Jinan 250003, China)

Abstract:Through analysis, it is found that the two-stage moving blade adjustable axial flow fan is frequently jammed because of the design, maintenance, operation mode and so on. According to the practice, the prevention, countermeasures are discussed and the improvement opinion is put forward，considering the design improvement, operation maintenance and overhaul. It can provide a reference for jamming issues of induced draft fan with similar condition.

Keywords:induced draft fan; moving blade adjustment; fault; preventive measures

2018-02-52Causeanalysisandtreatmentonthedifferentialpressureriseofairpreheaterintongchuanpowerplant

LIUZhao,RENTianbao(Huaneng Tongchuan Zhaojin Power Plant, Tongchuan 727100, China)

Abstract:Tongchuan Zhaojin Power Plant carries out an ultra-low emissions modification. As the denitration system is put into operation, the air preheater's differential pressure rises gradually. Through analyzing the causes of the rise of air preheater’s differential pressure and physical characteristics of NH4HSO4, temperature rising method can gasify NH4HSO4and carry it away with smoke, so as to achieve the aim of reducing air preheater's differential pressure and solve the problem of the air preheater clogging.

Keywords:denitrification; air preheater; clogging; NH4HSO4; temperature rising method

2018-02-54ComprehensiveperformanceanalysisofMGGHsystemaffectedbymultiplefactors

LUHairong，WANGGang，LIUGang(Suzhou Nuclear Power Research Institute Corporation Limited, Suzhou 215004, China)

Abstract:MGGH (Mitsubishi gas-gas heat exchanger technology) is popular with its energy saving performance. But performance evaluation on MGGH equipment only considers economic indicator such as flue gas temperature difference, pressure drop of the heat exchanger on flue gas side and overall pressure drop. The system resistance changes will affect the economy of related equipment after the operation of MGGH. At the same time, the influence of steam consumption, amount of desalinated water circulation and electricity consumption on the comprehensive performance of MGGH system should be considered. It should take adjustment to MGGH system to achieve the optimization. Taking a gas-gas heat exchanger system of a 1 000 MW unit, the current performance evaluation index can be improved with the combination of thermal test and will provide technical support for the unit operation.

Keywords:MGGH system; comprehensive performance evaluation; system resistance; economy

2018-02-57SimulationandoptimizationofMGGHsystemincoal-firedpowerplant

WANGZhengrong,GENGXuan,WANGYang,ZHANGXiqian(China Huadian Engineering Corporation Limited，Beijing 100160, China)

Abstract:MGGH system cycle water temperature at inlet and outlet determines the logarithm mean temperature difference of the heat exchangers, which affects the heat transfer area of cooling and reheat heat exchanger. At the same time, the materials of cooling heat exchanger and reheat heat exchanger are quite different because of the low temperature corrosion. The difference of materials makes the unit cost of these two heat exchangers varying widely. Therefore, the MGGH system was optimized by considering heat transfer area and material cost factor integrally. The MGGH system was built with the software Aspen plus and simulated numerically. Using the sensitivity analysis of the software, two variables which are the inlet and outlet temperature of cooling heat exchanger circulating water temperature in a power plant are set, to find out the optimal operating parameters. After optimization, the originally designed circulating temperature at outlet increases from 95 ℃ to 105 ℃, the required yield of circulating water drops from 619.677 t/h to 437.428 t/h, the total price of cooling heat exchanger and reheating equipment, reduced by 5.02% , and the total heat transfer area is increased by 1.55%.

Keywords:coal-fired power plant; MGGH system; low temperature corrosion; Aspen plus software; simulation optimization

2018-02-61Researchandapplicationofusingcirculatingdischargedwaterastheprocesswaterofdesulfurization

LIUXingchuan(Shanxi Luguang Power Generation Company Limited, Changzhi 046699，China)

Abstract:To save water and reduce waste water discharge, the circulating discharged water of power plant can be used for desulphurization. Through analyzing the quality of circulating discharged water from a certain power plant, it ensures that the circulation waste water can basically meet the quality requirements of pulping water and waste water treatment water in desulfurization process. Though there is scaling risk if it is used as the flushing water and cooling water, the circulation waste water has been added in scale inhibitor and corrosion inhibitor and keeps flowing, which make it difficult to scale. Taking circulating discharged water as the desulfurization process water, the investment will increase by 100,000 yuan, but the annual cost can be saved by about 4.11 million yuan, and the environmental protecting and economic benefits are prominent.

Keywords:circulating discharged water; desulfurization process water; water quality; environmental protection

2018-02-64Factorsinfluencingthedesignandselectionofthehoneycombfluegasdenitrificationcatalyst

LIXinyan,MENGFanqiang(Huadian Qingdao Environmental Protection Technology Company Limited， Qingdao 266000，China)

Abstract:Denitration catalyst is the core part of coal-fired power plant’s flue gas denitration system. It discusses and summarize three factors that will affect design and selection of honeycomb flue gas denitrification catalyst which are active damping coefficientβ, condition of flue gas and the requirements for performance guarantee. The ash content of flue gas determines the selection of catalyst pitch (hole). Active damping coefficientβ, O2content in flue gas, H2O content, reaction temperature and requirements for performance guarantee (denitration efficiency, oxidation rate of SO2and NH3escape) jointly determine the final catalyst volume.

Keywords:denitrification catalyst; design and selection; active damping coefficientβ; flue gas condition

2018-02-68Theselectionaboutthesulfurcontentinthecoalofultra-lowemissiondesulfurizationtransformationincoal-firedunits

LIZhuang，HUDa，WANGJianfeng，SUNHaifeng，ZHUYue(China Huadian Electric Research Institute, Hangzhou 310030, China)

Abstract:Sulfur content of coal was one of important factors that would affect the ultra-low emission desulfurization transformation. High-sulphur coal is of low cost but high cost of initial investment and operating. Choosing appropriate sulfur content of coal is of great significance for the power plant operation. Taking the limestone-gypsum wet desulphurization transformation project on a 300 MW coal-fired units in southwest as an example, it estimates the investments in the ultra-low emission desulfurization transformation schemes based on the different condition of as-received sulfur content in coal which are 3.85%, 2.43% and 1.06% (the corresponding factory price are 797，812，and 861yuan/ton). Taking the coal whose sulfur content is 1.06% as transformation scheme benchmark, taking annual cost method model，the investment payback period was 2.7 years and 3.5 years respectively when the as-received sulfur content in coal are 3.85% and 2.43%. It offers advice according to the power plant operating conditions, and provides the reference for the sulfur content selection for ultra-low emission desulfurization transformation in coal-fired units.

Keywords:ultra-low emission desulfurization transformation；coal-fired；sulfur content；investment payback period ；annual cost method model

2018-02-71Analysisandresponsetothemainabnormalitiesofdesulphurizationsysteminlowloadofcoal-firedpower

XUPing(Jiangsu Huadian Power Generation Company Limited, Zhenjiang 212300, China)

Abstract:It analyses the abnormal running situations of limestone wet desulphurization system in domestic coal-fired thermal power unit under low load running. It describes the formation of abnormal running, coping methods to the main abnormalities and provides feasible coping method for the safe and stable operation of desulfurization system.

Keywords:absorption tower seriflux foaming; slurry poisoning; stall；surge

2018-02-74ApplicationofcomputationalfluiddynamicssoftwareintheSCRdenitrationtechnologyofthermalpowerplant

SUNJingnan,WANGGuanyu,QINYiming,HANTongjiang(Huadian Qingdao Environmental Protection Technology Company Limited, Qingdao 266000，China)

Abstract:Take a selective catalytic reduction (SCR) denitration device of a 600 MW power plant as an example, it uses computational fluid dynamics (CFD) software, Ansys Fluent software ,to simulate the flow field of SCR denitration system. It shows the application situation of flow field simulation technology, points out the significance and future development direction of the flow field simulation for SCR denitration technology.

Keywords:selective catalytic reduction; denitration; computational fluid dynamics software; Ansys Fluent; flow field simulation