2018-11-01Researchondataerrordetectionmethodofheatingsystemsensor
LISilu1,LIUYaowen2,YUJingping3,FUQiang2,LIUHaibo2,ZHOUZhigang4,XUEPuning4,LIUJing4(1.MCC Huatian Engineering and Technology Corporation, Nanjing 210019,China; 2.Huadian Energy Thermal Network Testing and Technical Service Center, Harbin 150090,China; 3.Heilongjiang Construction Engineering Group Company Limited, Harbin 150046,China; 4.a.School of Architecture; b. Key Laboratory of Environment Science of Urban and Rural Residents in Cold Region and Technology Industry and Information Technology, Harbin Institute of Technology, Harbin 150090, China)
Abstract:In order to improve the accuracy of data uploading by central heating system, the identification method of error data is studied. Three methods including wavelet filtering, median filt-ering and error back propagation (BP) neural network are applied by the heat exchange station in the heating system. The data uploaded by the first level network traffic sensor are used to detect the error, and the results detected by the three methods are compared. It is concluded that the error detection method with the median filtering is the best.
Keywords:heating system; wavelet filtering; median filtering; error back propagation neural network; fault error detection
2018-11-05ApplicationofultrasonicbeamdiffusiontheoryinTOFDtechnology
GUANLei,LEIHai,DINGPeng,LIQin,XULing(Standard and Quality Control Research Institute,Ministry of Water Resources,Hangzhou 310012, China)
Abstract:Time of flight diffraction (TOFD )is used to test the weld. If other parameters are given, a probe with a higher frequency can reduce the height of the surface dead zone to a certain extent. However, considering the theory of sound beam diffusion, the probe with a higher frequency has a smaller sound beam coverage, which hinder full coverage of waves on the welds. Based on the ultrasonic beam diffusion theory, combined with the welding process and other factors, the reasonable probe parameters of work pieces with different thicknesses can be obtained, which can provide reference for relevant personnel to prepare the TOFD detection process.
Keywords:time of flight diffraction; surface dead zone; weld; sonic beam diffusion angle
2018-11-08Filtercircuitanalysisandtestoflocalizedprotectionmeasurementandcontroldevice
ZHANGBaoshan,ZHANGQunling,CHENGKejie,YANGJing,WANGMengqi,ZHAOYing(Xuji Electric Company Limited,Xuchang 461000,China)
Abstract:Correct sampling is the key technology to localized protection measurement and control device. According to the requirements of the protection and control device, a low-pass filter circuit with reasonable cut-off frequency should be designed to solve the problem of frequency aliasing. Since passing through the filter circuit will affect the amplitude and phase of the fundamental wave and harmonics, the corresponding compensation parameters need to be correct. It theoretical analysis the filter circuit cut-off frequency, amplitude and frequency characteristics as well as phase frequency characteristics,and protection program based on analytic results is designed. According to the amplitude and phase accuracy of the sampling value output of localization protection measurement and control device , the technical requirements of the localized protection measurement and control device are met.
Keywords:localized protection measurement and control device; sampling; low-pass filtering; frequency aliasing; amplitude frequency characteristics; phase frequency characteristics
2018-11-12Researchonthedetectiontechnologyofcorrosiondefectsontheheatingsurfacetubeinnerwallsofthepowerstationboiler
ZHUGuobin,JIAShaowei,WANGJingwei,JIANGYe,LIUWensheng,WANGDong(Datang Central-China Electric Power Test Research Institute, Zhengzhou 450000, China)
Abstract:Considering the limitation of the corrosion defects detection method for the heating surface tube inner walls of the current boilers in power plants, a special array low-frequency eddy current probe is designed. Combined with the requirements on the supervision and inspection of the heating tubes of boilers, contrast test tube samples with axial and circumferential artificial defects are made respectively to study the sensitivity of array low frequency eddy current test. Field application shows that the array low-frequency eddy current test can improve the detection efficiency of corrosion defects on the inner wall of the boiler heating surface tube, with less missing defects.
Keywords:heating surface tube of the boiler; inner wall corrosion; defects inspection; array low-frequency eddy current probe
2018-11-17Modificationofhightemperaturereheateranditsproblemsolving
HOUShengcun,CAOWei,WUYuegang,CAOLi(Huaneng Chaohu Power Generation Company Limited,Hefei 238015, China)
Abstract:A 600 MW supercritical coal-fired generator set in a power plant had stopped many times because of the weld desoldering of inverted U-bend and weld failure of dissimilar steel of high-temperature reheater since the commissioning. In this case, the power plant carried out the inverted U-bend transformation and displacement modification on dissimilar steel welding joints, according to the requirements of the factory. There has been no tube burst caused by inverted U-bend pipe cracking or dissimilar steel welding joints in the 3 years after the modification.The weld cracks of the small header pipe socket of the reheater appeared after transformation, can be solved by patching and repairing welding.
Keywords:high temperature reheater ;inverted U-bend; dissi-milar steel
2018-11-21ControlanalysisofXcriterionsbeforetheturbinerushesof1000MWsecondaryreheatunits
YELuo,DIAOHonghu,CUIXiaoguang(Guodian Taizhou Power Generation Company Limited, Taizhou 225300, China)Abstract:In 2×1 000 MW ultra supercritical secondary reheat steam turbine unit of second phase of Guodian Taizhou Power Plant, T3000 control system was taken as digital electro-hydraulic(DEH)control system.The DEH control system is equipped with thermal state estimator (TSE) for calculating and monitoring the heat stresses of various metal components of steam tur-bines in different starting modes. The X criterion is one of the basis for the judgment and control of TSE. The proper temperature margin can make the steam turbine have good adaptability and reliability under variable working conditions. By introducing the significance of the X criterion under cold, warm and hot conditions before the turbine rushes, the conditions and methods corresponding to meet X criterions are analyzed, which provides a reference for the smooth turbine rushes of similar type.
Keywords:turbines; secondary reheat; turbine rushes; X criterions; digital electro-hydraulic (DEH); thermal state estimator(TSE)
2018-11-24Gasturbineexcitationprotectionactiontrippingaccidentanalysisandprocessing
JIANGZhihui,WANGYaokun(Zhuhai Yuhai Power Company Limited,Zhuhai 519055, China)
Abstract:The maloperation case of a gas turbine over-excitation protection was analyzed to find out the cause of the protection maloperation. The hidden danger was eliminated by adding a harmonic elimination low-voltage potential transformer (PT).Countermeasures are proposed to prevent malfunction protection and improve the protecting function.Countermeasures can provide reference for the subsequent problems of the secondary side voltage distortion caused by the ungrounded operation mode of the primary side of the PT.
Keywords:gas turbine generator;excitation protection;no grounding system;potential transformer(PT); harmonic;protection trip
2018-11-27Causesandpreventivemeasuresforheatingsurfaceleakageofwasteheatboilerofgasturbinepowerstation
LUDingkang,XUJianguo,QIANSongfeng(Jiangsu Huadian Qishuyan Power Generation Company Limited, Changzhou 213000, China)
Abstract:The reliability of the pressure-bearing components of the waste heat boiler of a gas turbine power station determines whether the boiler can operate safely for a long time. Taking a waste heat boiler of a gas turbine power plant as an example, typical cases of heating surface leakage are analyzed, and preventive measures and treatment schemes are proposed, which can provide reference for the inspection and maintenance for the pressure-bearing parts of the waste heat boiler.
Keywords:waste heat boiler; pressure-bearing components; leakage; flow-accelerated corrosion; stress; preventive measures
2018-11-31Diagnosisofvacuumdropof680MWultra-supercriticalunit
DONGLin1,ZENGYajie2,SHENYang1,LIUMingxing1,ZHANGZhiyong1,MAYong3(1.Huadian Electric Power Research Institute Company Limited, Wuhan 430000, China; 2.Commissioning Branch of POWERCHINA Hubei Engineering Company Limited, Wuhan 430000, China; 3.Xi’an Thermal Power Research Institute Company Limited, Xi’an 710032, China)
Abstract:In view of the vacuum drop occurred during the operation of unit No.4 in a power plant, the vacuum system was checked for leaks within a helium mass spectrometer. Through leak detection, adjustment and analysis of the suspected areas, it is found that the breakage of the shaft seal pipe of the B steam feed pump turbine is the cause of the vacuum drop. After replacing the shaft seal pipe, the problem of vacuum reduction of the No.4 was effectively solved.The condenser vacuum returned to normal, and the vacuum tightness test passed.
Keywords:ultra-supercritical; vacuum drop; shaft seal; helium mass spectrometer; leak detection; vacuum tightness test
2018-11-34Staticanalysisofboomstructureofflat-headtowercranebasedonANSYS
YUHongzhu(SEPCO III Electric Power Construction Company Limited, Qingdao 266000, China)
Abstract:The mass of the flat arm tower boom takes a large proportion of the whole machine’s. Optimizing the design of the boom structure can greatly improve the economics of the whole machine. The structure of the boom is briefly introduced. By analyzing various working conditions of the boom, the control conditions of the boom are obtained. The limit state method is used in designing and calculating the boom structure,which is verified by ANSYS software. The maximum stress and displacement nephogram of the boom structure under different working conditions are obtained, which can provide data basis for optimizing design for the boom structure.
Keywords:flat-head tower crane; boom structure; static analysis; ANSYS software; limit state method
2018-11-36FiniteelementanalysisoflowerbearingringbeamofPZQ1400attachedself-liftingtowercrane
ZHAOXiaowei,ZHANGQian,SHIXiaofei,ZENGGuang(Huadian Zhengzhou Mechanical Design Institute Company Limited, Zhengzhou 450015,China)
Abstract:Taking the lower bearing ring beam of PZQ1400 tower crane as the analysis object, it considers two kinds of dangerous working conditions. Via the software Creo, an 3D finite element model of the ring beam is set up and imported into the workbench to carry on the finite element analysis. By comparing with the strength of ring beam obtained by traditional computing,the rationality of model simplification and loading is explained.It provides a method for designingthe structure of the type.
Keywords:tower crane;ring beam;Creo;workbench; finite element analysis
2018-11-40Boilerandpressurevesselsafetysupervisioninqualitysupervisionstationsduringthethermalpowerconstruction
HUANGYouchang(Sichuan Guangan Power Generation Company Limited, Guang’an 638550, China)
Abstract:In combination with the thermal power unit installation project, it discussed how the quality supervision station carries out safety supervision on boiler and pressure vessel effectively according to the regulations and standards.It also does discussion on the supervision content incompletely.
Keywords:quality supervision station; boiler; pressure vessel; safety supervision
2018-11-42Theeffectandimprovementschemeonunfavorabledrainingofshaftsealingpipeline
CHENGTu1,YULifan2(1.Jiangsu Huadian Qishuyan Power Generation Company Limited, Changzhou 213000, China;2.Hangzhou Huadian Xiasha Thermal Power Company Limited, Hangzhou 310018, China)
Abstract:It introduces and analyzes the abnormal conditions and measures taken during pipe warming and operation of shaft sealing system of a unit. The improvement scheme has been calculated and explained, which can be used as a reference for the same type of problems in units.
Keywords:pipeline draining; shaft seal temperature;separation of steam-water flow; slope; drainage tank
2018-11-45Causeanalysisandimprovementmeasuresofoilsystemfaultsinfeedwaterpumpsturbine
SUNGuoqiang(Henan Branch of China Huadian Corporation Limited, Zhengzhou 450046, China)
Abstract:Taking 2×330 MW units of a company as an example, the problems that one of the main oil pumps tripped during the operation of feed water pump turbine and another feed water pump turbine tripped during its abnormal joint since the pressure of lubricating oil was low are analyzed. Through theoretical analysis and field test, the reasons for the low joint oil pressure of the oil pump are found out, and the corresponding improvement measures are implemented to improve the safety of the unit operation.
Keywords:feed pump steam turbine; oil system; oil pump; tripping; lubricating oil
2018-11-48Testandresearchofthelowvoltageride-throughinfluenceontheconverterofcoalfeeder
HANFeng1,YUCheng2(1.Control Technology Laboratory,Zhejiang Energy Group Research Institute, Hangzhou 310000, China; 2. Zhejiang Energy Lanxi Power Generation Company Limited, Lanxi 321100, China)
Abstract:In order to avoid the power plant tripping due to low voltage disturbance of the power plant which triggers the protection action of the unit, the test of the influence of low voltage on the converter of the coal feeder was carried out according to the specific conditions of the equipment of Zhejiang Energy Lanxi Power Generation Company Limited. It proposed a method of low voltage ride-through for coal feeder frequency converter of direct-firing pulverizing system with middle speed mill.
Keywords:coal feeder; frequency converter; low voltage ride through
2018-11-52Technologyandapplicationofanewprefabricatedoverheadinsulationpipe
GUJinglei1,ZHONGShengkai2(1.Ningbo Wanli Pipeline Company Limited, Ningbo 315800, China; 2.Institute of Thermal Science and Power System, College of Energy Engineering, Zhejiang University, Hangzhou 310027, China)
Abstract:It analyzes the disadvantages of traditional overhead insulation pipes that are widely used in heating projects. Accordingly, a new prefabricated overhead insulation pipe and its characteristics are introduced. Compared with traditional overhead insulation pipes, its advantages of short construction period, high cost performance and strong thermal insulation performance are clarified. The actual cases show that within the new prefabricated overhead insulation pipe, the energy consumption of the heating project is significantly reduced, and the environmental protection and economic benefits are remarkable.
Keywords:central heating; overhead insulation pipe; prefabricated insulation pipe
2018-11-55Analysisandprecautionontubeburstinginlow-temperaturesuperheaterofboiler
CHENXianxian,FANGJue(Huadian Electric Power Research Institute Company Limited, Hangzhou 310030,China)
Abstract:There was a tube bursting in the low-temperature superheater of supercritical unit in a power plant.Through macro inspection, metallographic analysis and electron microscopy, combining previous start-up and shutdown inspection status, maintenance status, abnormal operation and the initial design of the boiler, it is discovered that oxidized scale falling off which leads to tube blockage and short-term overheating is the cause to the tube bursting. Effective preventive measures for operating statuses are proposed, which effectively improve the safety and economy of the units.
Keywords:low-temperature superheater; tube bursting; oxidized scale
2018-11-57Measurestoreducetheexhaustlossofgasboilerdeaerator
WUMinjie,TANGMingfeng(Hangzhou Huadian Xiasha Thermal Power Company Limited, Hangzhou 310018, China)
Abstract:The exhaust loss of deaerator accounts for 87.69% of the total steam loss of gas boiler. In order to improve the economic efficiency of gas boiler in heating operation, measures should be taken to reduce the deaerator exhaust loss. Through analysis, it is confirmed that both excessive and lacking intake water will lead to an increase of deaerator exhaust loss rate. When the load is low, feeding water is heated by admission from the bottom. When the load is high, the feeding water is heated mainly by admission from the top and assisted by admission from the bottom. The measures effectively reduce the exhaust gas loss rate and the gas-heat ratio of the gas boiler, and the annual natural gas cost can be saved by about 720 000 yuan.
Keywords:gas boiler; heating; deaerator; exhaust loss; economy
2018-11-59Safetyanalysisofboilerstakenlow-nitrogenburnerreformation
CUIXiuqiang(Technology Service Branch of Huadian Power International Corporation Limited, Jinan 250014, China)
Abstract:After low-nitrogen burner reformation, the combustion instability of a company occurred in several units. The impacts of the reform on the safety, economy and nitrogen oxide emissions of the boiler were analyzed. Focusing on the five reformed units that have been in loss of ignition, analyzed from the aspects of boiler check calculation, retrofit installation, cold state acceptance and thermal state adjustment, useful suggestions for the modification and operation optimization for low-nitrogen burners are proposed.
Keywords:low-nitrogen burner; transformation; safety; loss of ignition; optimization adjustment
2018-11-62Problemsandoptimizationofheatingnetworkcirculatingpumpsets
ZONGXudong(Technology Service Branch of Huadian Power International Corporation Limited, Jinan 250014, China)
Abstract:The heating network circulating water pump is an important power equipment in the heating system, which directly affects the heating safety and economy. The operation status of each heating network circulating water pump set in every company of Huadian Shandong Company is diagnosed from the driving mode, model selection and configuration.The typical problems such as cavitation erosion, high power consumption rate and large steam throttling loss are pointed out and the optimization plan is put forward.
Keywords:heating network circulating water pump; heating system; small steam turbine; driving mode; model selection; configuration; power consumption rate; efficiency
2018-11-65Analysisonlifemanagementtechnologyofregeneratedcatalystincoal-firedpowerplants
YINShun1,LUZhifei2,YOUJiyi1,LIUChangdong1,ZHAOHuimin1(1.Zhejiang Energy Catalyst Technology Company Limited, Ningbo 315612, China; 2.Fengtai Power Generation Branch,Huaizhe Coal and Electricity Company Limited, Huainan 232131, China)
Abstract:The life management of denitration catalyst is an important means to reduce the cost and ensure effect of denitration. Both the regenerated catalyst and the new catalyst have problems in life management and employ different life management techniques. Combined with the characteristics of the deactivated catalyst and the cause of deactivation, the life management technology of the regenerated catalyst and the whole process of its regeneration application are detailed from the design and implementation of the regenerative production process, operation of regenerated catalyst,overhaul and maintenance, etc. It provides reference for the regeneration of the deactivated denitration catalyst and the application of the regenerated catalyst for coal-fire power plants.
Keywords:life management; denitration; catalyst; regeneration
2018-11-68Economicanalysisofcogenerationsystemcombinedcooling,heating,powerandsteamdrivenbynaturalgas
CHENJing1,2,JIANGTing1,2,XUJingjing1,2,HUYongfeng1,2,LIYue1,LIUGuangyu1,2(1.China Huadian Engineering Corporation Limited, Beijing 100160, China; 2.National Energy Distributed Energy Technology Research and Development Center, Beijing 100160, China)
Abstract:The distributed energy system driven by natural gas has the characteristics of being close to users, energy echelon utilization, low carbon, high efficiency, clean and environmental protection. Distributed energy system can provide users with various forms of energy such as cooling in summer , heating in winter, domestic hot water, steam and electricity. Taking a pharmaceutical industrial park as research object, it provides a kind of cogeneration system combined cooling,heating, power and steam. Installed configuration is given through the analysis of load, economic analysis and sensitivity analysis on the cogeneration system. The results show that there is a positive linear relationship between electricity price , steam price and system economy, while static investment , natural gas price have a negative linear correlation with system economy.Establishing a linkage mechanism between the price of cold,hot,electricity and the price of natural gas is conducive to improving the economic efficiency and reducing the operating risk of the project.
Keywords:distributed energy system; cogeneration system; economic analysis
2018-11-72Researchandapplicationofcoolingstoragesolutioninthenaturalgasdistributedenergystation
WANGXueqin1,JIANGTing2,XUJingjing2,DENGYa’nan2,HUYongfeng2(1.Shanghai Branch of China Huadian Corporation Limited,Shanghai 200126, China; 2.Huadian Distributed Energy Engineering Technology Company Limited, Beijing 100070, China)
Abstract:The natural gas distributed energy station has been vigorously promoted and demonstrated in recent year due to its characteristics of clean, high efficiency, safety and environmental protection. The users and load of natural gas distributed energy system are complex and changeable. The energy storage system has a good function of cutting peaks , filling valleys and balancing load. A certain scale of energy storage system can be deployed in the distributed energy station, which can optimize the operation strategy and improve the economics of the system. It takes the cooling supply method of a building type distributed energy station in Shanghai as the research object, and establishes two cold storage schemes which are ice storage scheme and water storage scheme. According to the operation mode and economy analysis, the water storage scheme that adopts waste heat to storage has an 83.2% annual comprehensive utilization rate on average.It is more economical and feasible than the ice storage scheme.
Keywords:natural gas distributed energy; cold storage scheme; economic analysis