Power Equipment

Archive

  • Select all
    |
    Research & Analysis
  • Research & Analysis
    Research and Analysis on the Internal Efficiency of CHP Steam Turbine Under Variable Test Conditions
    Feng Yaofei, Feng Linkui, Gu Zhide, Zhao Kai, Wang Ping
    2023, 37(3): 141-146,158. https://doi.org/10.19806/j.cnki.fdsb.2023.03.001
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Through the variable-condition tests and the isentropic equilibrium method, the change of the internal efficiency of steam turbine and the internal efficiency of each steam cylinder was researched under different power loads and different extraction steam flow rates for combined heat and power (CHP) steam turbine, while a simulation calculation was conducted on the trend of the internal efficiency of steam turbine under different extraction positions according to the equivalent enthalpy method. Based on the reheat theory, the low pressure cylinder efficiency was calculated from the combination of the equivalent relationship between the internal efficiency of steam turbine and the internal efficiency of each steam cylinder. Calculation results show that, under the variable test conditions with different parameters, with the increase of the power load and the extraction steam flow rate, the internal efficiencies of the steam turbine, the high pressure cylinder and the low pressure cylinder all show a trend of increasing, while the internal efficiency of the medium pressure cylinder shows a trend of decreasing. Among the losses of the steam turbine, the proportion of the cold source loss is major, and the proportion of the work loss is secondary. With the increase of the extraction steam flow rate, the output power proportion of the low pressure cylinder decreases, while the output power proportions of the high and medium pressure cylinder increase.
  • Research & Analysis
    Analysis on Energy Efficiency of a High Temperature Steam Heat Pump System with Waste Heat Recovery
    Jiang Xin, Lu Qiliang, Li Zheng, Chen Pei, Lu Wanglin, Wu Guanghua, Qi Wen, Jiang Xi
    2023, 37(3): 147-152. https://doi.org/10.19806/j.cnki.fdsb.2023.03.002
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Taking a high temperature steam heat pump system with waste heat recovery as the research object, the thermal calculation and the comparison of the coefficient of performance (COP) were carried out under different steam production flow rates and different temperatures of low temperature heat source, while an analysis was conducted on the economy of the system. Calculation results show that, the system can be optimized with a higher COP by adding the regenerator and changing the interstage temperature. With the application of the regenerator, when the steam production flow rates are 1 t/h and 5 t/h, the coefficients of performance can be improved by 2.0% and 1.8%, respectively. The COP of the high temperature steam heat pump system with two-stage cascaded design changes with the change of the interstage temperature, and the COP of the system reaches the maximum value when the interstage temperature is 64 ℃. Compared with other types of steam generators, the high temperature steam heat pump system has a lower energy cost, but the initial investment is still high at present. With the reduction of the initial investment, the high temperature steam heat pump system will have a broad application prospect.
  • Research & Analysis
    Flow Field Analysis and Abrasion Research of Flue Duct in Front of the Low Temperature Economizer
    Wang Liang, Li Xiaoquan, Wang Jie
    2023, 37(3): 153-158. https://doi.org/10.19806/j.cnki.fdsb.2023.03.003
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    To avoid the problem of the corrosion and abrasion with large-scale of the flue duct in front of the low temperature economizer in a coal-fired power plant, based on CFX software, the flow field analysis and abrasion research was conducted for the flue duct, and the optimal design structure parameters were obtained through optimizing the structure of the flue duct. Results show that, by controlling the ratio of curvatures of the flue duct within 0.80-0.96, the distribution uniformity of the fly ash particles in the outlet section of the flue duct is improved, while the abrasion velocity of the flue duct with the curved section can be reduced. This may serve as a reference for similar units with the presented significant optimized effects.
  • Research & Analysis
    Design and Simulation for the Lubricating Oil System with Electric Main Oil Pumps in Steam Turbine
    Gong Xiangchen, Zhang Zijian, Gao Chao, Zhang Di
    2023, 37(3): 159-165. https://doi.org/10.19806/j.cnki.fdsb.2023.03.004
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Based on Flowmaster software, a model with static balancing and dynamic simulation was established for the lubricating oil system with electric main oil pumps in a set of steam turbines. Simulation results show that, during the switching process between the alternating current (AC) main and auxiliary oil pumps, and between the direct current (DC) emergency oil pump and the AC oil pump, the valve opening can be automatically controlled by the self-operated oil overflow valve with the change of the main-pipeline pressure of the lubricating oil system, so as to adjust the discharge oil flow, while the main-pipeline pressure can be maintained in the rated value. The oil pressure fluctuation of the lubricating oil system can be improved through the setting of the pressure sampling point of the self-operated oil overflow valve in the main-pipeline of the lubricating oil system. The fluctuation of the main-pipeline oil pressure can be alleviated with the accumulator during the switching process of pumps. The operation requirements of the lubricating oil system under different conditions can be satisfied by the setting of two accumulators with 100 L volume through simulations.
    • Design & M anufacture
  • Design & M anufacture
    Discussion on Type Selection and Configuration for Main Engines in a Large Gas-Steam Combined Cycle Unit
    Wu Jing
    2023, 37(3): 166-170. https://doi.org/10.19806/j.cnki.fdsb.2023.03.005
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Taking a large gas-steam combined cycle unit in Sichuan province as the research example, analyses were conducted on the type selection of gas turbine, steam turbine, waste heat boiler, the shafting configuration of the unit, etc. The optimal configuration scheme was obtained through the comparison between 9F and 9H class gas-steam combined cycle units on the technicality and economy. Results show that, the 9H class gas-steam combined cycle unit has a higher initial investment. When the annual utilization time is 2 500 h, the 9H class gas-steam combined cycle unit has a shorter investment payback period, while when the annual utilization time is more than 3 500 h, the economy of the 9H class unit is significantly better than that of the 9F unit.
    • Nuclear Technology
  • Nuclear Technology
    Discussion on Qualification Method of Class 1E Electrical Connectors in VVER Nuclear Power Plant
    Yuan Dongying, Chen Gongming, Yang Xiao
    2023, 37(3): 171-175. https://doi.org/10.19806/j.cnki.fdsb.2023.03.006
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Combined with the operation conditions in the containment of a VVER nuclear unit, the domestic and foreign qualification standards of electrical connectors, RCC-E standard specifications, and Russian qualification documents, the qualification scheme was put forward for the electrical connectors at the top of the domestic class 1E reactor in the VVER nuclear power unit. Discussions were conducted on the determination of each test parameter and the technical problems in the test process, while corresponding suggestions and measures were proposed. This may serve as a reference for the qualification of the electrical connectors in VVER nuclear power units.
  • Nuclear Technology
    Application Research of Domestic PEEK Materials in Electrical Penetration Assemblies
    Shen Peng, Quan Xiande, Wu Keke, Yang Wenjian, Huang Wenjun, Zhang Hui, Tu Chongwen
    2023, 37(3): 176-180. https://doi.org/10.19806/j.cnki.fdsb.2023.03.007
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    A study was conducted on the application process of domestic polyetheretherketone (PEEK) material of the electrical penetration assembly in a nuclear power plant. Results show that after long-term accelerated thermal aging test, irradiation aging test, anti earthquake test, and simulation test of accident and serious accident conditions, the sealing performance and electrical performance of following domestic PEEK materials can be adopted to satisfy the application requirments of the electrical penetration assembly in nuclear power plants, such as NC770G/NC550G type, and crystalline NC551LG type.
    • Material Technology
  • Material Technology
    Fracture Analysis on the Last Stage Rotating Blade of Steam Turbine of Feed Water Pump in a Power Plant
    Zhou Yang, Fu Wen, Li Yanchao
    2023, 37(3): 181-185. https://doi.org/10.19806/j.cnki.fdsb.2023.03.008
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    An analysis was conducted on the fracture of the last stage rotating blade of the steam turbine of feed water pump in a power plant through the macroscopic inspection, chemical composition analysis, mechanical properties test, metallographic examination for the fracture blade, and the macroscopic inspection, scanning electron microscopy, energy spectrum analysis for the fracture position. Results show that the fracture of the last stage rotating blade of the steam turbine of feed water pump presents the fracture type of high-cycle fatigue. The genenration of the crack is caused by the repeated action of the higher alternating stress. The genenration of the crack is promoted with the reduced strength of blade resulted from the corrosion pits on the blade surface and fracture source area, which finally leads to the fracture.
    • Automatic Control
  • Automatic Control
    Research on Early Warning Method for Rotor Vibration Based on BP Neural Network
    Huang Yangsen
    2023, 37(3): 186-191. https://doi.org/10.19806/j.cnki.fdsb.2023.03.009
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    A prediction model was established for the vibration of an electric generator rotor based on back propagation (BP) neural network, and the training sample of BP neural network was constructed by using the sliding window. The early warning method of the rotor vibration was proposed with the operation condition of the electric generator and the relative deviation between the operation value and the predicted value of the rotor vibration, while the early warning method was verified by the operation data of an electric generator in a power plant. Results show that, the proposed early warning method for the rotor vibration of the electric generator is feasible, and this can satisfy the application requirements for the online early warning of the rotor vibration.
    • Operation & Retrofit
  • Operation & Retrofit
    Research on Retrofit of the Heating System with Extraction Steam from Reheat Hot Section in a 1 000 MW Unit Based on EBSILON
    Zeng Haibo, Chen Zhuo
    2023, 37(3): 192-197. https://doi.org/10.19806/j.cnki.fdsb.2023.03.010
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Based on the evaluation model established by EBSILON software, a simulation research was carried out for the heating system with extraction steam from the reheat hot section in an ultra-supercritical 1 000 MW coal-fired unit, while a calculation and analysis was conducted on the influence of the mass flow rate of extraction steam for heating within 0-450 t/h on the main parameters and thermal economy of the unit. Research results show that, under different boiler load conditions, the heat rate of electricity generation is decreasing in a linear fashion with the increase of the heating steam flow rate. Under the lower boiler load condition, the heat rate of electricity generation has a significant decrease with the increase of the heating steam flow rate.
  • Operation & Retrofit
    Analysis and Treatment on the Fault of Generator Rotor in a 9E Gas Turbine
    Zhang Xuelin
    2023, 37(3): 198-202. https://doi.org/10.19806/j.cnki.fdsb.2023.03.011
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    To eliminate the fault founded in the detection for the 9A5 generator rotor in a 9E gas turbine, the design defect of this type of generator rotor was analyzed, and the treatment for the fault of the generator rotor was introduced. Results show that, the fault location can be further confirmed by the static measurement with eight angles, and this type of fault can be eliminated through improving the process. This may satisfy the requirements of the frequent start-up in the gas turbine generator units.
  • Operation & Retrofit
    Analysis and Treatment on the Burnout of Ignition Air Duct in a 350 MW Supercritical CFB Boiler
    Wang Yingqi, Du Hongfei, Yan Xinglei, Lü Jian, Zhang Qin
    2023, 37(3): 203-206. https://doi.org/10.19806/j.cnki.fdsb.2023.03.012
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    An introduction was conducted on the structure of ignition air duct and the mode of air distribution of a 350 MW supercritical circulating fluidized bed (CFB) boiler, and analyses and discussions were carried out for the castable shedding with large area and the burnout of the ignition air duct in the first ignition process of the boiler. The accident of the under-bed ignition burner in the CFB boiler can be effectively prevented by adopting following measures, such as adjusting the output of oil gun, distributing the air reasonably for the burners, optimizing the logic, etc. This may serves as a reference for the debugging and operation of the similar boilers.