Abstracts

2018-05-01Studyonevaporationcharacteristicsofbrineinsprayevaporationprocessatambienttemperature

ZHAOBaohua1,GAORan2,WENJiaqi2,YIZuyao1,HANZhengfei1(1.Huadian Zhengzhou Designing and Research Institute, Zhengzhou 450046, China; 2.College of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, China)

Abstract:China encourages “nearly zero discharge” of industrial wastewater, and advanced treatment of brine is of great deep concern. Desulfurization wastewater, mining wastewater and other industrial wastewater can be processed by spray evaporation technologyat ambient temperature. On the self-built outdoor test beds for spray evaporation test, the evaporation rate of brine was measured and the characteristics of evaporation products were described by scanning electron microscope (SEM). Smaller atomized particulars lead to a larger evaporation rate. When the particle diameter is over 500 μm, decreasing the size of particular has small effect on evaporation rate. Smaller salinity leads to a larger evaporation rate, but the difference is slight. The spray evaporation rate has an approximately linear positive correlation with the wind velocity, exponential positive correlation with temperature, and a negative correlation with the relative humidity. The wind velocity is the decisive factor of the spray evaporation rate as wind velocity is large. When the relative humidity is over 90%, humidity is the decisive factor. When the temperature is less than 15 ℃, the temperature is the main factor . The mechanical atomization rate of the test is about 4～12 times of natural evaporation rate.At the same time, it is noted that there is wind loss in spray evaporation rate, and measures should be taken to avoid the secondary pollution caused by water of high salinity.

Keywords:spray evaporation;mechanical atomization; desulfurization wastewater; brine; desalination; nearly zero discharge; evaporation rate

2018-05-08AnalysisandimprovementonlogicdesignofG60generatorprotection

LIUFang，WANGDongya(Zhuhai Jinwan Power Company Limited, Zhuhai 519000, China)

Abstract:There are many protection changes on GE generators since#3 and#4 units of Zhuhai Jinwan Power Company Limited got into operation in 2007. G60 protection on generators includes 500 kV switches full stop protection, CT disconnection, loss of excitation protection and wave recording startup. The problems of secondary circuit wiring and logic design are analyzed and improved to optimize the protection function of generator, which guarantees safe production.

Keywords:generator; generator-transformer unit; protection logic; switches full stop protection; loss of excitation protection; wave recording startup; secondary circuit

2018-05-13ACCdesignoptimizationforgasturbinecombinedcycleunits

QIUYonggang(Shanghai Electric Power Generation Engineering Corporation, Shanghai 201612, China)

Abstract:According to the basic principles of heat transferring，it creates a mathematical model of heat transferring area and power consumption of ACC affected by initial temperature difference (ITD) and head wind velocity. Taking an F-class one-plus-one CCPP as an example, it calculates the influence of ITD and head wind velocity on net output and ACC heat transferring area of power plant and obtains the optimized ACC design parameters.

Keywords:direct air cooling condenser; heat transfer coefficient; head wind velocity; ITD; heat transferring area; net output; power consumption of ACC

2018-05-17Researchonstatusandapplicationprospectoflocallyinstalledprotectionofintelligentsubstation

LILiangyu,TANGBaofeng,ZHAOXianlong,ZHANGJi,ZHENGZiyao(State Grid Hebei Economic Research Institute, Shijiazhuang 050021, China)

Abstract:On the basis of the status quo of the locally installed protection，the scheme of locally installed protection is proposed.The characteristics of single-master scheme and full-master scheme are compared for cross-interval protection. It focuses on single-master scheme of transformer protection and the full-master scheme of busbar protection.The key technical issues of locally installed protection are pointed out.Current progress of research and development of localized protection devices is summarized and the application scenarios for locally installed protection is prospected.

Keywords:intelligent substation;locally installed protection；cross-interval protection；single-master scheme；full-master scheme；key technologies

2018-05-21Researchonriskassessmentandinformationmanagementofboilerheatingsurfaces

ZHAOXiaopeng1,ZHAOFei2,NIYongzhong2(1.Ningxia Jingneng Ningdong Electric Power Company Limited, Yinchuan 750400，China; 2.North China Electric Power University, Beijing 102206，China)

Abstract:The main reason for unplanned outage is the bursting and leakage of heating surfaces of power plant boiler. According to the status quo of passive inspection and maintenance on power plant anti-wear and explosion proof, a concept of digital management on boiler anti-explosion and anti-explosion work is put forward. Wall temperature of boilers are analyzed, assessed and graded from various aspects. The risk assessment model of heating-surface pipe is established. The equivalent creep lifetime loss caused by over-temperature is introduced into the evaluation model. Combined with off-line testing data, the risk level of the heating-surface tube is amended dynamically, which can improve the assessment reliability of the risk indicators.

Keywords:anti-explosion and explosion proof; over-temperature; 3D visualization; risk assessment

2018-05-25MultivariablemodelingofthemainsteamtemperaturebasedonfielddataandPCA

HOUXiaoning(Huadian Zhengzhou Mechanical Design Institute Limited Company，Zhengzhou 450046，China)

Abstract:As the main steam temperature system is a multivari-able and strong coupling system, a large number of field operational data is collected. Through principal component analysis(PCA)，five main variables are extracted from 11 procedure variables as the input of the main steam temperature system. Simultaneously, the mechanism modeling, experimental modeling and intelligent optimization algorithms modeling are combined. Finally, the multiple-input single-output multivariable model is established by using the field data. This solution solves the problem of frequent and large-scale step disturbance tests in which it is not allowed or cannot to get to the productive site. It overcomes the uncertainty of the range of initial values and model structure for multivariable intelligent optimizing, and established a multivariable model that can be used for studying main steam temperature system control.

Keywords:main steam temperature; multivariable modeling; principal component analysis; field data

2018-05-30MagnanimousDTUinformationacquisitionC/SmodelbasedonepollmechanisminLinux

FUXueliang,LIDejun(Nanjing SAC Power Grid Automation Company Limited，Nanjing 210000, China)

Abstract:With the rapid development of distribution automation in our country, the traditional distribution collection model cannot meet the demand of large-scale real-time massive power distribution terminal. Power distribution network data acquisition has become a key technique of large-scale distribution master station. Analyzing the characteristics of Linux epoll mechanism, we design a magnanimous networking communicating information processing model which combines multithreaded synchronization and data access mechanism. It studies the model design and the implementation of epoll mechanism under C/S model.It guarantees the timeliness and safety of distribution information whenthere is large scale of clients and service terminal type distribution terminal.

Keywords:Linux；epoll；multithreaded synchronization;DTU; information acquisition;C/S model

2018-05-33Controlstrategyonsteamtemperatureof1000MWdoublereheatunits

HUZunmin，YUGuoqiang，SHUJianjun，ZHANGTianhai(Jiangsu Fangtian Power Technology Company Limited, Nanjing 211102, China)

Abstract:Taking 1 000 MW double reheat units of Guodian Taizhou Power Generator Company Limited, it introduce the control principle of superheated steam, first and second reheat steam temperature for tower type double reheat boiler. Analyzing steam temperature’s control logic on proportion, integral and derivative (PID), it proposes a control logic for steam temperature regulating equipment of 1 000 MW double reheat units which can provides reference for unit control logic configuration and optimization of double reheat units.

Keywords:tower type boiler; double reheat units; steam temperature; control logic

2018-05-38RefinementandanalysisonalarminformationsystemduringthegasturbineSFCstart-up

GUYiyang1，XIAOLiming2(1.Jiangsu Huadian Qishuyan Electric Power Company Limited, Changzhou 213011,China; 2.School of Electronic Information Engineering, Nanjing University of Information Science and Technology, Nanjing 210044,China)

Abstract:Gas turbine generally adopts the static frequency converter (SFC) as startup mode of electric drive. The SFC system has a complex logic system, and its faults affects the start-up and operation of the whole unit. Mastering the principle of SFC system and improving alarm information system can speed up the problem solving of electric driving, save the time for the paralleling to the grid, and ensure the normal start of the unit. Through practical tests and exploration a solution optimization scheme is put forward to solve the general problems in SFC operation.

Keywords:gas turbine; static frequency converter (SFC); start-up; electric drive; alarm information

2018-05-41Analysisandregulationonvibrationofhightemperatureandhighpressurepipe

BUZhengrong1,CHENGYongming2,ANFuli2,LIUBin2(1.Mawan Power Plant of Shenzhen Energy Group Company Limited, Shenzhen 518054, China; 2.Xi’an Thermal Power Research Institute Company Limited, Xi’an 710054, China)

Abstract:In order to solve the problem of excessive vibration at hot reheat steam pipe, field investigation, vibration measurement and data processing on pipe vibration are carried out to analyze the vibration characteristics of the pipeline. It points out that regulation on vibration should be made from three dimensions which are eliminating the turbulence force, improve the piping vibration characteristics, and maintain the level of primary stress and secondary stress level as far as possible. It puts forward a scheme to install vibration damping device on the premise of ensuring qualified stress of pipe system. The pipeline vibration is effectively controlled after treatment.

Keywords:pipe; vibration; vibration characteristics; vibration damping device

2018-05-45Analysisonpowerreliabilityof600MWandabovecoal-firedunits

HANQin,FANHuijian,LIUZhanli(Huadian Electric Power Research Institute, Hangzhou 310030, China)

Abstract:To improve operational reliability of 600 MW and above coal-fired units ，it analyzed the factors affecting the reliability of 600 MW and above coal-fired units of 2016. It is concluded that the poor quality of maintenance, poor quality of products and fuel affection are the main reasons for the unplanned outage of the units， among which the poor quality of maintenance is the dominant reason. Unplanned outages caused by boilers accounted for the largest proportion of unplanned outages caused by the three main equipment. Blockage, steam leakage, oil leakage, water leakage, great vibration, jam, abrasion, high temperature, corrosion, cracks and so on, are the main factors affecting the reliability of auxiliary equipment.

Keywords:600 MW and above coal-fired units; power reliability; unplanned outage; boiler; auxiliary equipment

2018-05-50Animprovedphraseselectiondeviceofdoublecircuitlinesonthesametower

ZENGXianhua(Guodian Nanjing Automation Company Limited, Nanjing 210003, China)

Abstract:Analyzing the faulty features of the double circuit lines on the same tower and the existing conventional mutation of phase selection device that accrues in cross-line fault, a new method is proposed to deal with phrase selection based on mutant phase selection of double circuit lines. After the fault of system, phase selection device should adjust the proportional relation between the offset voltage and the voltage mutation according to the magnitude of the fault current, recognize the simple fault in internal area and complex fault in external area, input phase selection device adaptively. In view of cross-line fault of double circuit lines, a new phrase selection method is put forward, which effectively solve the mistaken choice of mutation phrase selection device while dealing with the cross-line fault, improve the security of the power system operation, stability and reliability of the transmission.

Keywords:double circuit lines on the same tower; phase selection element; cross-line fault; mutations

2018-05-53Anti-freezingkeypointsofdirectaircoolingunitinwinteroperation

RENLiang(Huadian Xinjiang Power Generation Company Limited, Changji Thermal Power Station,Changji 831100, China)

Abstract:The anti-freezing method of 330 MW direct air cooling co-generation unit operating in winter, especially in the extreme cold weather, is still in experience accumulation and exploration period. According to the existing operation mode, continuous optimization and adjustments,such as raising the back pressure of units, starting the standby vacuum pump and exit isolation column, are made to meet the winter anti-freezing requirements and overcome the code winter.

Keywords:direct air cooling; operation and adjustment; anti-freezing

2018-05-56Causeanalysisandtreatmentofhighmoisturecontentofgypsumin1050MWunit

CHENLi1，WUChunchao2(1.China Energy North China Electric Power Test and Research Institute Company Limited, Tianjin 300162, China； 2.Xinjiang Production and Construction Corps Hongxing Power Generation Company Limited, Hami 839000, China)

Abstract:Aiming at the problem of high moisture content of gypsum in a 1 050 MW unit, the influence factors such as the quality of limestone powder, the quality of the absorber, the vacuum pump, the vacuum degree of vacuum belt dewatering machine and the solid amount in underflow of the swirl are investigated. The main reason to determine the high water content of gypsum is the low installation precision of vacuum belt dewatering machine, and the cracks in gypsum results in the reduction of vacuum degree. The secondary reason is that the pH of the absorber slurry is high and the gypsum crystal is rare. By taking corresponding measures, the high water content of gypsum is solved.

Keywords:gypsum; moisture content; vacuum belt dewatering machine; vacuum degree; crack

2018-05-58Optimizeddesignofautomaticgenerationcontrolsystematplantlevel

DAIXihui(Guangdong Honghaiwan Generation Company Limited, Shantou 516623, China)

Abstract:In order to achieve the economic distribution of load among different units in plant, Guangdong Honghaiwan Generation Company Limited launch a set of external plant level automatic generation control (AGC) system. AGC command turns from the original load command for single unit to load command for the whole plant. After acceptance of load command for the whole plant, load optimization calculation is made by plant level AGC server. It introduces the construction of plant level AGC system, structure and process of software at plant level, and summarizes the key designing points of AGC system. After the operation of the system, accuracy of every channel, the load command distribution, load change rate and response to primary frequency modulation can satisfy the requirements of grid. The load distribution right of each unit is obtained by the plant side.

Keywords:plant level automatic generation control system; optimization; load distribution

2018-05-61Causalanalysisonthecarbonbrushcordpeelingofffromthe390Hgeneratorexcitation

NIUZhifeng(Jiangsu Huadian Qishuyan Power Generation Company Limited, Changzhou 213011, China)

Abstract:It introduces the structural characteristics of 390H generator excitation carbon brush. Comparing and analyzing the original parts and replaced parts from structures and craftsmanship, it points out that ordinary carbon brush cord embedding process is not applicable to this type of carbon brush, which is the main cause of carbon brush cord peeling. It can be taken as reference for selecting carbon brush and operational maintenance for generator excitation.

Keywords:generator; carbon brush; brush cord; peeling off; embedding process

2018-05-63Themethodofenergyconservationandenvironmentalprotectionbygeneratingelectricitywithfallingwaterofcoolingtower

YUDechao1,WUWeiyu2(1.China Huadian Yongzhou Wind Power Company Limited, Changsha 410004, China; 2.Hunan Electric Power Design Institute Corporation Limited of China Energy Engineering Group, Changsha 410007, China)

Abstract:It introduces a reconstruction scheme of cooling tower in thermal power station. It adopts and combines the existing materials and devices to utilize the energy of falling water of cooling tower. It solves the environmental problem of noise, prevents the anti-crosswind and reuses cooling water, which increases the efficiency of the device and the cooling effect of cooling towers.

Keywords:cooling tower; reconstruction; noise reduction; crosswind; energy recovery; efficiency; environmental protection; wind deflector.

2018-05-68AnalysisandcountermeasureofmainfactorsaffectingcomprehensivewaterconsumptionrateofSilinPowerPlant

HOUGuangqiang(Silin Power Plant，Guizhou Wujiang Hydropower Development Company Limited, Sinan 565109，China)

Abstract:The water consumption rate of Silin Power Plant，Guizhou Wujiang Hydropower Development Company Limited is relatively high. The external environment of unit operation is analyzed from the function of power plant in power grid, reservoir operation characteristics and relationship between upstream and downstream reservoirs. The main factors affecting water consumption rate are analyzed from the internal environment which includes adjustment of time between overhauls, load fluctuation per unit and single unit operating condition. It takes measures such as the dynamic control of reservoir water level, the improvement on the accuracy of small flood forecast and the optimizing the starting sequence of units, to effectively reduce the water consumption rate of power plants.

Keywords:Silin Power Plant; comprehensive water consumption rate; external environment; internal environment

2018-05-70Designandapplicationofwaterlevelmeasurementsystemforboilerdrumofwasteheatboilerindistributedenergystation

DONGShumei1,YULi1,DUJuhu2(1.China Huadian Engineering Company Limited， Beijing 100070，China; 2.Huadian Distributed Energy Company Limited，Beijing 100070,China)

Abstract:The reliability of water level measurement signalof waste heat boiler drumin regional distributed energy station is directly related to the safe operation of waste heat boiler and steam turbine equipment .Therefore，the water level measurement system of waste heat boiler drum is one of the most important system for thermal measurement. Taking the water level measurement to a high-pressure drum of double pressure waste heat boiler as an example, the key designing points of water level measurement system are analyzed and studiedfrom configuration of measuring instrument for water level of drum, drum instrument measuring principle, the configuration and the corresponding correction method for balance container of differential pressure type level gauge, the drum water level control and processing of protective signal.

Keywords:water level of boiler drum;configuration of measuring instrument; configuration of balance container;adjustment of protective signal

2018-05-73Briefanalysisonthedevelopmentanddesignofbuildinggasdistributedenergysupplysystem

YULi1, 2(1.China Huadian Engineering Company Limited， Beijing 100070,China; 2.Huadian Distributed Energy Company Limited， Beijing 100070，China)

Abstract:Natural gas distributed energy has developed rapidly in China in recent years. It analyzes the factors that influence the economic efficiency of building gas distributed energy supply system and puts forward the suitable development conditions. At the same time, the key designing points of building gas distributed energy supply system, the requirements for energy station location and layout are put forward.

Keywords:building gas distributed energy; natural gas prices; time for heating and cooling; condition and scale

2018-05-75Analysisofhighvoltagefaultofsupercapacitorinwindturbinepitchsystem

LIYa’nan(State Grid Shanxi Changzhi Power Supply Company, Changzhi 046011,China)

Abstract:Analyzing pitch capacitor’s high voltage fault in Vensys pitch system of a wind farm in Inner Mongolia. Analyzing the cause of fault and check them item by item, it is found out that while taking manual pitch control, the output voltage of pitch capacitor voltage monitoring module is less than 54 V after 3 s .The voltage return to normal after terminating the pitch system . After replacing the supercapacitor, the unit return to normal operation.

Keywords:wind power unit; pitch system; supercapacitor; voltage