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    Summary & Survey
  • Summary & Survey
    Research Progress of Anti-icing Superhydrophobic Coatings for Wind Turbine Generator Blades
    Ni Yifan, Zhang Zuogui
    2024, 38(1): 1-6. https://doi.org/10.19806/j.cnki.fdsb.2024.01.001
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In cold winter weather, the blades of wind turbines are susceptible to icing, which would seriously affect the efficiency of power generation and even cause the shutdown of wind turbine generator. To ensure the safe and efficient operation of wind turbine generators, the research progress of superhydrophobic coatings was reviewed, while the application advantages and existing problems of superhydrophobic coatings for anti-icing were summarized. Results show that, the anti-icing technology with superhydrophobic coatings for wind turbine generator blades has a promising application prospect. However, further researches should be carried out in the durability and engineering preparation of coatings.
    • Research & Analysis
  • Research & Analysis
    Study on the Effect of Coal and Sludge Co-firing on Heating Surface in Coal-fired Boiler
    Li Mingming, Hou Bo
    2024, 38(1): 7-12. https://doi.org/10.19806/j.cnki.fdsb.2024.01.002
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Based on the sampling analysis of city sludges from Chengde, Fuzhou and Changzhou, taking a 630 MW coal-fired boiler of a power plant in Jiangsu Province as the application object, theoretical analyses were conducted on the abrasion,slagging, fouling and corrosion of heating surface according to blended fuel parameters, while tests were carried out for the near wall reducing atmosphere with different sludge blending ratios in the power plant. Under the circumstance of the application of design fuel and a certain blending ratio, besides the reducing gas content exceeds the empirical value in several measure points, the effect of co-firing of coal and sludge on heating surface in the coal-fired boiler could mainly satisfy the design requirements.
  • Research & Analysis
    Research on Online Monitoring of Oxide Layer Growth Based on Furnace Wall Temperature Calculation
    Li Tao, Jin Wangzong, Wang Hongwei, Zu Yonghai, Zhang Tianyin, He Dong
    2024, 38(1): 13-17,23. https://doi.org/10.19806/j.cnki.fdsb.2024.01.003
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    An online thermodynamic calculation model of the boiler heating surface was established based on the real-time operation data of the boiler. The difference between the calculated temperature of the outlet of heating surface and the measured value of actual point was taken as iteration termination condition, so as to obtain the flue gas and working fluid temperature of boiler superheater inlet and outlet. The steam temperature and metal wall temperature of each section of the heating surface tube were calculated by segmentation calculation method. The average metal wall temperature of each section was selected as the calculated temperature for oxide layer growth, and the calculation period was set to 2 min. The incremental and cumulative values of the oxide layer thickness of the platen superheater were calculated. The calculated results are in good agreement with the actual measurements, and the online monitoring of the thickness of oxide layer on the heating surface of boiler is realized.
    • New Energy
  • New Energy
    Analysis on the Net Revenue of Electrochemical Energy Storage Power Station in Shandong Province Based on Electricity Spot Market
    Wang Xiao, Zhou Haini, Fan Yunpeng, Bian Feng, Wen Yiqian, Chen Na, Han Xiaogang, Mu Qiang
    2024, 38(1): 18-23. https://doi.org/10.19806/j.cnki.fdsb.2024.01.004
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The relevant policies in Shandong province under the background of electricity spot market were summarized. The calculation formula of the net revenue of the electrochemical energy storage power station was obtained by analyzing the income and expenditure of the power station. The critical point electricity price difference under typical working conditions was studied by analyzing the relationship between the net revenue of power station and on-grid electricity, electricity price difference, comprehensive efficiency, and the application of "charging twice and discharging twice" strategy. The effectiveness of the formula was verified by case analysis of an operational 100 MW/200 MW·h electrochemical energy storage power station in Shandong province. The research results can provide a reference for optimizing the operation strategy of power stations and improving the income of power stations.
    • Automatic Control
  • Automatic Control
    Application of Optimal Scheduling Technology for Auxiliary Equipment in Thermal Power Plants Under Spot Electricity Price Condition
    Jiang Tao, Wang Guangbing, Jiang Jie, Liu Long, Song Yichun
    2024, 38(1): 24-29,46. https://doi.org/10.19806/j.cnki.fdsb.2024.01.005
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Based on the fluctuation of the next day's spot electricity price curve and the following considerations of various factors, such as unit operation needs, raw material preparation capacity of auxiliary equipment and storage capacity, the specific software for the optimal scheduling of auxiliary equipment in thermal power plants was developed. The software can automatically make a start-stop plan one day in advance for auxiliary equipment that can be operated at different time periods. The results of theoretical analysis and software functional show that optimizing scheduling of some auxiliary equipment can not only improve the electricity sales revenue of thermal power plants, but also facilitate the consumption of some electricity during low electricity consumption periods, and further improve the stability of power grid operation with good economic and social benefits.
  • Automatic Control
    Application on Intelligent Soot Blowing Model of Thermal Power Plant Based on Time Sharing Linearity
    Ma Xiaochun, Liu Xianghong, Chen Jing, Zheng Yunlin, Guo Li, Zhao Taotao, Zhao Weijie
    2024, 38(1): 30-35. https://doi.org/10.19806/j.cnki.fdsb.2024.01.006
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    A model of slagging process was established based on the long and short term memory (LSTM) algorithm, so as to develop a furnace water wall slagging monitoring model. An intelligent soot blowing system for boiler based on a distributed control system (DCS) was further implemented. This system achieves intelligent soot blowing, automatic drainage, and automatic stop during boiler operation. It ensures the safety of the heating surfaces in the boiler. After implementing the intelligent soot blowing method in a thermal power plant, the total frequency of soot blowing can be significantly decreased. This system effectively reduces the frequency of soot blower operation, decreases the steam consumption during soot blowing, lowers the exhaust gas temperature.
    • Operation & Retrofit
  • Operation & Retrofit
    Analysis and Treatment on the Abnormal Rotor Vibration Case in a 1 000 MW Unit Generator with Damping Bar Runout
    Yang Yulei
    2024, 38(1): 36-41. https://doi.org/10.19806/j.cnki.fdsb.2024.01.007
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    For a 1 000 MW steam turbine generator unit during paralleling operation after maintenance, a detail introduction was conducted on the whole process of analysis and treatment for the abnormal increase of vibration amplitude with the increase of load. The reason of abnormal rotor vibration was analyzed from the aspects of the unit operation data, variable operation condition test, rotor inter-turn insulation diagnosis, and rotor sampling inspection, while combined with the unit maintenance, the rotor damping bar ventilation holes were offset and enlarged. Results show that, the severe thermal imbalance of rotor under high-load operation condition was caused by the damping bar runout with the blockage of some ventilation holes, which results in the abnormal rotor vibration. The adverse effect of the damping bar runout on the abnormal rotor vibration is completely eliminated through the offset and enlargement for the ventilation holes.
  • Operation & Retrofit
    Analysis and Treatment on the Fault of Intervel Channel Temperature Protection in a SGT5-8000H Gas Turbine
    Liu Runze
    2024, 38(1): 42-46. https://doi.org/10.19806/j.cnki.fdsb.2024.01.008
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Based on the measuring point arrangement and protect logic of interval channel temperature protection in a SGT5-8000H gas turbine, an introduction was conducted on the two faults related to interval channel temperature protection and their treatments. Results show that, for the fault of several measuring points for interval channel temperature protection caused by the card fault, the interval channel temperatures all return to normal values through changing the faulty card to the new card online. For the spread protection fault during unit start-up, combined with analyses on the interval channel temperature deviations among burners, the gas turbine can start smoothly after the cleaning for the filters of gas intake nozzle.
    • Special Column: Analysis and Treatment for Materials in Power Units
  • Special Column: Analysis and Treatment for Materials in Power Units
    Failure Analysis of Boiler Water Wall Tubes Leakage Accident
    Lin Xinghao, Wang Meihuan, Zhang Linghan, Huang Fangjian, Jiang Peng, Yang Lei, Zhang Hao, Shi Zhigang
    2024, 38(1): 47-52. https://doi.org/10.19806/j.cnki.fdsb.2024.01.009
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The leakage accident of boiler water wall tubes in a power plant was analyzed. The macroscopic detection, chemical composition analysis and mechanical property testing of the leaking failed tubes were carried out. The metallographic observation and fracture morphology analysis of the tubes and its fillet weld were carried out. Results show that, the main cause of the water wall tubes leakage is the poor welding quality of the fillet weld between water wall tubes and the fin. During the operation process of the water wall tubes, the cracks in fillet weld expand along the grain from outside to inside continuously, and penetrate the tube wall, at last cause the leakage of the water wall tubes.
  • Special Column: Analysis and Treatment for Materials in Power Units
    Analysis and Treatment on the Leakage of High Pressure Evaporator in Waste Heat Boiler
    Zhou Baicheng
    2024, 38(1): 53-56,61. https://doi.org/10.19806/j.cnki.fdsb.2024.01.010
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    To solve the problem of the leakage of the high pressure evaporator of a waste heat boiler in a gas-steam combined cycle unit, a comprehensive analysis was conducted on the failure mechanism and cause of the high pressure evaporator by means of macroscopic inspection and sampling analysis, while corresponding countermeasures were proposed. Results show that, the increase of the vaporization rate is resulted from the blockage by alien objects, and with the abnormal phase transition of the working medium occurring at the position of 1.5-5.2 m away from the high pressure evaporator header, the water content is decreased through the change of steam water mixture to saturated steam. The deposition and scaling in the inner wall of the high pressure evaporator is in process with the decrease of the dissolution of salt, which leads to the deposition corrosion. The leakage of the high pressure evaporator is finally caused by the reduction of the tube wall thickness.
  • Special Column: Analysis and Treatment for Materials in Power Units
    Fracture Analysis and Supervision Discussion on the Bolt of a Turbine High-pressure Inner Cylinder
    Cheng Xiang, Zhang Jie, Jin Shasha, Pan Yingfeng
    2024, 38(1): 57-61. https://doi.org/10.19806/j.cnki.fdsb.2024.01.011
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    To solve the problem of the fracture of a 20Cr1Mo1VNbTiB steel bolt of high-pressure inner cylinder in a power plant steam turbine, analyses were conducted on the fracture reason from the aspects of non-destructive testing, macroscopic examination, chemical composition analysis, microstructure analysis, hardness testing and mechanical property testing, while corresponding suggestions were proposed for the supervision and inspection of 20Cr1Mo1VNbTiB steel bolts. Results show that, the bolt contains the original large particle inclusions from the manufacturing process, while the decomposed internal cementite and carbide aggregate with alloy elements at the grain boundary, which leads to the decrease of impact toughness of material. The crack from the first thread propagates along the grain boundary under the long-term action of alternating load, which finally leads to the fracture of the bolt.
  • Special Column: Analysis and Treatment for Materials in Power Units
    Analysis on the Leakage of Final-stage Reheater Tube in a Boiler with Long-term Service
    Bai Zhenfeng
    2024, 38(1): 62-66. https://doi.org/10.19806/j.cnki.fdsb.2024.01.012
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    For a 600 MW subcritical unit with the operation time of 140 000 hours in a power plant, the leakage of the final-stage reheater tube in the boiler occurred. By means of macroscopic observation, metallographic analysis, scanning electron microscope (SEM) observation, energy dispersive spectrometer analysis, X-ray diffraction (XRD) analysis, hardness test and tensile property test, analyses were conducted on the leaked 12Cr1MoV steel tubes in the final-stage reheater. Results show that the leaked 12Cr1MoV steel tube has the obvious microstructure aging with the spheroidization grade of 4. Meanwhile, Brinell hardness is decreased to 103HBW, and the yield strength is lower than the standard value. The blockage of the lower elbow of U-shape tube is resulted from the peeling oxide layer from the inner wall of reheater tube in the unit with long-term service, which leads to the serious overtemperature of the straight section in steam admission side. The leakage and burst of tube would occur with the comprehensive effect of the microstructure aging and property degradation of 12Cr1MoV material, and the thinner tube wall caused by the peeling of a large amount of oxide layer.