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RSS2019 Vol. 6, No. 2
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2019, 6(2): 1-6.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.001
Abstract:
[Introduction] This paper aims to promote the establishment of a complete technical standards system for offshore wind farms. [Method] The problems existing in the construction of offshore wind farms in China were pointed out, the standards for offshore wind farm facilities at home and abroad were summarized, and the exploration and effectiveness of the technical specifications for offshore wind power facilities by China Classification Society(CCS) were introduced. [Result] Despite the rapid development of offshore wind power in China, the supporting technical specifications for offshore wind power facilities have not been followed up in time, and the whole life cycle technical specifications system, including design, construction, installation, operation and maintenance and abandonment, has not been established. Although Europe has a mature specifications system for offshore wind power facilities, it cannot be completely copied and used, such as the LRFD method of structural design which is related to the environmental conditions and reliability index of the sea area, and the partial factor applicable to the European sea area is not applicable to the Chinese sea area. [Conclusion] Therefore, the technical specification system for the domestic offshore wind power facilities requires the joint efforts and cooperation of the industry, traditional ocean engineering specialty should play a greater role in this field, and the research achievements by CCS in this field can provide some reference values for the establishment of the technical specification system.
2019, 6(2): 19-28.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.004
Abstract:
[Introduction] To develop the technical and economical efficiency of traditional photovoltaic (PV) power generation, new type dual-axis tracking PV power generation technology is proposed, that focuses on the solution to the fixed PV on water surface. [Method] A new type of ground and water-based dual-axis tracking PV power generation technology was provided, where single-axis PV arrays were arranged on a large disc supported by trusswork structure, and rotated very slowly with a fixed center.Based on the layout of PV array, the land and energy utilization of this new system were analyzed. Moreover, compared with the traditional PV, the technical and economic analysis, which indicated the increasing of power generation and cost of the new system, was achieved. [Result] The new dual-axis tracking system conserve land, which would only cover about 50% of the area for the traditional dual-axis tracking technology.The proposal system increases power generation. The dual-axis tracking type system increases by 35%~45% compared with the fixed PV system. The water surface PV will increase by another 6%~15%.Stable period of power generation could be achieved fastly.Only one azimuth and altitude angle detection device are needed for new dual-axis tracking system. One driven device could satisfy the azimuth angle tracking and altitude angle tracking system could be driven by centralized power supply in different regions. The technical and economic indicators are better, especially compared with the traditional water surface PV system.Easy operation and maintenance could be available. Gantry crane frame structure is adopted, and it is convenient to repair and clean the steel truss with equal spacing moving forward, backward, left and right, up and down. [Conclusion] The new dual-axis tracking system is more economical, power generation more stable and more convenient maintanence, which could have popularization prospect.
2019, 6(2): 29-33.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.005
Abstract:
[Introduction] Because of the low temperature parameter, the power generation efficiency of the small modular PWR nuclear power plant is less than 30%. [Method] In order to improve the efficiency of the nuclear energy utilization, the small modular reactor can be combined with the renewable energy and the advanced supercritical CO2 cycle was used as the thermal energy conversion device. Based on a supercritical CO2 cycle with a simple regenerative mode, adding one intercooling and one reheating, a new hybrid power generation system was integrated with a small reactor and a solar energy source and a biomass energy source, and the efficiency of the power generation was analyzed. [Result] The results show that the power generation efficiency is 34.13% and 41.22% for the system with the inlet temperature of the high pressure turbine at 390 ℃ and 550 ℃, respectively. In addition, the analysis of the safety of the system shows that the CO2 itself has the nuclear safety property, and the supercritical CO2 cycle can also be used as the passive waste heat discharge system of the reactor to ensure that the reactor continuously exhaust the decay heat under the severe accident condition. [Conclusion] Supercritical CO2 cycle power system integrated with small modular reactor and renewable energy source has good power generation efficiency and nuclear safety.
2019, 6(2): 34-37.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.006
Abstract:
[Introduction] The initial investment and operation cost of the power plant are significantly increased after the ultra-low emission configuration is selected for the project of new coal-fired power units. The main purpose of this paper is to carry out detailed technical research on how to optimize the design to improve the operating economy of the units and give recommendations. [Method] By combining theory with practice, this paper selected a 1 000 MW unit project for practical study. [Result] The results show that the application effect of the project is significant, and the main economic and technical indicators are leading in China. The optimization design results and research methods recommended in this paper have been verified accordingly. [Conclusion] The relevant research results of this paper can provide important reference for the construction of similar projects in the future.
2019, 6(2): 38-42.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.007
Abstract:
[Introduction] In order to ensure the normal operation of the flue gas system of boiler, after the domestic coal-fired power plant is implemented with ultra-low emission reform, the induced draft fan and the booster fan need to be reform. [Method] Taking a 1 000 MW coal-fired unit as an example, the three possible reforming schemes of the induced draft fan and the booster fan (only the induced draft fan was changed, the booster fan was only changed, and the induced draft fan and booster fan were merged) were compared from the technical aspect, and made an economic calculation based on the actual unit. [Result] The result shows the merger scheme has lower cost. [Conclusion] This comparison method and modification scheme have high reference value for the induced draft fans reformation of other coal-fired power plant.
2019, 6(2): 43-48.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.008
Abstract:
[Introduction] The coal dust pollution mainly occurs at transfer point, and have not been effectively controlled by the traditional equipments and dust removal technologies. This paper aims to study several new clean transport technologies to fundamentally control coal dust pollution and meet environmental standards. [Method] On the basis of summarizing the origin of coal dust pollution and current technical defects, combined with typical examples, the principles and characteristics of new technologies, which were dry mist dust suppression, IFT(3-DEM), non-power dust removal groove and so on, were analyzed and carried out technical and economic comparisons. [Result] Research shows that the new technologies have high reliability and wide application range, and can effectively control coal dust pollution during coal transportation. The actual effect meets environmental protection standards and has good social and economic benefits. [Conclusion] New clean transport technologies can solve the environmental problems faced by coal dust pollution, it is recommended to apply in projects.
2019, 6(2): 49-53.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.009
Abstract:
[Introduction] According to the offshore wind farms layout and typical delivery scheme of Guangdong area, the paper discusses the two joint delivery schemes of 300 MW offshore wind farm. [Method] From the aspects of electrical single line diagram, submarined cable′s selection, reliability analysis, cable laying and supply, comparable investment and so on were compared. [Result] To provide an optimization for the joint delivery of offshore wind farm, setting two 220 kV offshore booster station and one onshore control center, one of the booster station connect to another with one 3×1 000 mm2 submarine cable, then sent out with two 3×1 000 mm2 submarine cable to onshore control center. [Conclusion] The scheme of two joint delivery schemes of 300 MW offshore wind farm can save the investment and reduce the area of sea which offers reference for the prospective electrical design of offshore wind farm.
2019, 6(2): 54-58.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.010
Abstract:
[Introduction] The paper aims to obtain the optimal layout of offshore wind farm and gain the maximum profit in the project life-cycle, it is high necessary to analyze its impact factors. [Method] The own developed application was used to compare the wake models between Jensen and Larsen, different superposition algorithm among wind turbines and the interannual variability of wind direction, this disquisition had combined the practical offshore wind farm case to analyse and provide the optimal layout. [Result] The results we obtained demonstrate that the interannual variability of wind direction is the most key factor to layout, followed by the different wake model, with superposition algorithm least. [Conclusion] This work provides some guidance for further project on choosing the optimal layout, thus the billions of dollars in losses caused by interannual variability of wind direction can be avoided in life-cycle of 25 years.
2019, 6(2): 59-63.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.011
Abstract:
[Introduction] With respect to the flat topography wind farm, wind speed and wind direction present significant regional difference in complex terrain region, which bring great challenges to the selection of generator, wind turbine layout, production assessment. To solve these problems that may occur during micro-sitting in complex terrain region such as wind measurement mast, contour, restricted factors. [Method] This paper detailedly analysed and discussed these problems based on the collected wind data, associated with the author′s work experience, and illustrated the significant influence of restricted factors on the generation of wind farm. [Result] Confirming the accurate location of the wind measurement mast, marking the restricted areas at the topographic map via field investigation. Checking the accuracy of the contour value by creating elevation grid from 3D vector data, making contrast analysis with the value of the contour lines. [Conclusion] Practice has proved that accurate site of the mast and high-quality wind data play an important role during wind energy resource assessment, the identification of restricted areas can shorten the time required to develop a layout plan and improve the work efficiency. With accurate topographic map, wind resources in the wind farm and surrounding areas can be accurately simulated, which can provide quality assessment results for investors.
2019, 6(2): 64-69.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.012
Abstract:
[Introduction] Multi power transmission lines arranged in the same corridor could avoid the land division and reduce the adverse effect on the local planning and development, but the personal safety of operators in the process of towers and conductors erection of subsequent power lines should be seriously considered as a result of induced voltage of the previous energized transmission lines. [Method] One DC transmission line under construction was taken as an example, electrostatic induced voltage generated from multi UHVDC transmission lines nearby in the same corridor were studied and calculated. The influence factors including the operating mode of UHVDC lines, line spacing from the energized power lines and length of stringing conductors were analyzed at the same time. [Result] The results show that the induced voltage got significantly high from adjacent UHVDC lines, and operation mode of energized lines played an important part; the less line spacing reduce, the higher induced voltage reach; the steady-state current from ion current density generated by UHVDC lines flowing through construction equipments have nearly less impact to constructors. Induced voltage of the stringing conductors will be paid much attention to when stringing and conductors and equipments should be grounded effectively. [Conclusion] The research results also have guiding significance to power lines′ construction which be adjacent to live lines.
2019, 6(2): 70-76.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.013
Abstract:
[Introduction] In flexible HVDC transmission systems, HVDC converter valve power modules and their spares are tested and maintained at regular intervals. The power modules in good condition are essential to assure the safe and steady operation of flexible HVDC transmission systems. [Method] Firstly the structure, working mechanism and shop test items of power modules were analyzed in view of the shortage of relevant specifications and standards for power modules on-site test. Then a power module test method suitable for actual situation on site was proposed. Based on the proposed method, a device able to test power modules automatically was developed. [Result] The proposed test method and device effectively improve the completeness, efficiency and accuracy of power module on-site test, which is applied in Sucheng converters station of Nan′ao multi-terminal HVDC flexible system. [Conclusion] The engineering practice indicates that the proposed method provides an effective way for the power module test tasks during the phase of operation, maintenance and inspection, which is close to the actual test situation on site. Moreover, the proposed method and device provide a reference for the power module test tasks of other flexible HVDC transmission systems.
2019, 6(2): 77-83.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.014
Abstract:
[Introduction] The design of transmission pole and tower has a significant impact on the project cost and the surrounding environment. Exploring the design method and economic index of 220 kV single circuit composite tower is of positive significance to the optimization of transmission lines. [Method] Firstly, the recommended scheme was obtained by comparing different tower forms, composite cross-section forms and cross-section arrangement. Then the linear and non-linear analysis of tower was carried out by ANSYS software to understand the difference between the two analysis methods. Then found out the relevant information, calculated the cost of common and composite pole towers, and explored their economy. [Result] Compared with Cathead Tower, Wine Cup Tower and Top Pyramid Tower, it is more reasonable to apply composite crossbars in Top Pyramid Tower; ring section has the advantages of larger moment of inertia, higher bearing capacity and convenient processing and connection; 220 kV straight tower can reasonably choose more economical structural layout form on the premise of satisfying safety, and it is recommended to choose three-pull-one-press layout scheme through ANSYS simulation analysis shows that the linear analysis has enough accuracy and can be designed by linear analysis. When selecting composite crossbar, the related factors such as tower cost, installation cost, relocation compensation and so on should be taken into consideration, and the technical and economic comparison on the engineering quantity should be made, so as to obtain a more reasonable scheme. [Conclusion] The research results are of universal significance and can provide some technical support for the design of composite tower in the future.
2019, 6(2): 84-88.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.015
Abstract:
[Introduction] The paper aims to research the settlement regular and mechanism of the ash dam according to the similarities and differences of measured settlement and conventional settlement regular analysing results. [Method] Firstly, the conventional settlement regular and mechanism of shield construction were introduced in details. Secondly, the settlement regular of the ash dam was researched by the measured settlement curve of the tunnel through the ash dam, and the measured settlement, numerical simulation of settlement and conventional settlement regular were comprised and analysed. Finally, the causes of the sudden change of the settlement of the ash dam were analysed, and the settlement mechanism of the ash dam was obtained. [Result] The results show that the stone riprap of ash dam is large and uneven, its cohesive force is poor, and its gap is large, thus lead to shield excavate difficulty and easy to cause over-excavation and under-excavation, which is the reason for the difference between ash dam settlement and general settlement law. After the shield tunneling, all the measuring points are sliding towards the tunnel palm face rapidly, shows that there are some external factors causing formation deformation and mutation, the law of actual measurement is obviously inconsistent with the general law. The recombination of ash dam stone riprap structure causes the stratum to slip to the palm face, the surface subsidence mechanism of ash dam is obtained. The results of this paper also show that the ash dam reinforcement is very important to the shield construction safety. [Conclution] The research results can provide references for other similar projects.
2019, 6(2): 89-93.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.016
Abstract:
[Introduction] In order to improve the efficiency and quality of laser point cloud data processing and provide data guarantee for tree barrier detection for transmission lines. [Method] A new automatic point cloud classification algorithm was proposed based on the self developed laser radar UAV, then a tree barrier analysis software was developed based on the algorithm to realize one-click automatic classification of point cloud. [Result] The results show that the accuracy of point cloud classification can reach more than 95%, and the efficiency of point cloud automatic classification can reach 60 km/h, moreover, good classification results are achieved in the complex areas where the towers and power lines, towers and vegetation intersect each other. [Conclusion] This method provides a high efficiency, high quality, automatic and intelligent data processing method for the analysis of tree barrier danger, and effectively improves the acquisition accuracy and processing efficiency of geospatial three-dimensional information data.
2019, 6(2): 94-98.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.017
Abstract:
[Introduction] The application of arial surveying on heat disposal to the ocean from nuclear power plants involves multiple issues. [Method] The article introduced the issues include surveying technics, characteristics of survey area, surveying situations, and safety control, then summarized the measure by four sections which were the drone system applied, how to gather maritime temperature data around the nuclear power plants, how to monitor the fluctuation of maritime temperature with arial spectral instruments in summer tides; analysis of heat expansion in different tide conditions based on the data gathered. Finally, the results based on the measured data were summed up in the paper. [Result] The practice shows that the procedure is approved reliable and can precisely gather information of temperature increment from power plant heat disposal in this task. [Conclusion] The arial surveying on heat disposal to the ocean from nuclear power plants has many advantages over manual surveying.It can provide powerful reference for future research in how heat disposal affect the environment.
2019, 6(2): 99-105.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.018
Abstract:
[Introduction] Cycle load has effect on the rock strength and mechanical characteristics and China still lack the research on dynamic characteristic parameter of mechanism of medium weathering sandstone. [Method] According to test physical parameters of 90 medium weathering sandstones, the deep and velocity of sonic were presented as power founction, then MTS machine was used to conduct cyclic load test in different amplitude obtain the sample′s law of hysteretic cycle, dynamic elastic modulus, axial strain and damping ratio in axial cyclic load. [Result] The results show that the velocity is increasing with the increasing of the depth. The density of sample approximate 2.50 g/cm3. The axial strain and plastic displacement are increasing with the increasing of rounds. The increasing area of hysteretic cycle means that rock inner cracks is creating continuously resulting to increasing consumption of energy.The form of hysteretic cycle is same as sharp leaf and what it′s sharp but not around in the time of increasing stress or decreasing stress means that the sample reflection of changing stress is rapid and the plastic displacement in the time of changing stress is little relatively. The dynamic elastic modulus is increasing and damping ratio is decreasing with the increasing of dynamic strain. The math relations between either elastic modulus or damping and dynamic strain is presented as linear. The correlation coefficient R2 is almost above 0.85 showing good relevance. [Conclusion] This work provides some guidance for further study on testing and evaluation of dynamic characteristic parameters for soft rock foundation of nuclear power plant.
2019, 6(2): 106-111.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.019
Abstract:
[Introduction] This paper aims to describe all kinds of key points and key factors in cost management of distribution network project, and also provide reference for further normalization and standardization of future cost management work of distribution network project. [Method] We checked a lot of literature materials, summarized advanced experience of several typical developed countries in pricing system and cost management model, and discussed some problems in project management and cost management of China′s distribution network project. [Result] The results show that the cost management methods of distribution network projects are not uniform, and the pricing rules are complicated. The accuracy and timeliness are ineffective, then there offen appears "data barriers" and "information islands" phenomenon. [Conclusion] Finally, combining with the actual requirements of distribution network project cost management, this paper put forward that whole-process and intelligent are the inevitable trend of cost management development in the future. It also suggests several rationalization proposals, which includes promoting intelligent and digitalized development of distribution network project cost, improve the pricing basis, creating a favorable market environment, strengthening whole-life cycle cost management and fine enterprise management.
2019, 6(2): 112-117.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.020
Abstract:
[Introduction] Inorder to improve the reliability requirements and effectively reduce energy consumption, the paper proposes a comprehensive solution for a mains + natural gas distributed energy system and analyze the technical feasibility and economy of the solution, and give support for the choice of the solution. [Method] To verify the feasibility of the solution, we took a certain data center as example, comparative analyzed the consumption and the distributed energy system of the project. [Result] The results we obtained demonstrate that compared with conventional data centers, data centers supporting natural gas distributed energy systems have certain advantages in reducing energy consumption. The solution has certain economics, when natural gas prices, cold prices and electricity prices are properly matched. [Conclusion] The solution and economics this work provided are correct and effective and can provide guidance for investment decisions in natural gas distributed energy projects.
2019, 6(2): 118-123.
doi: 10.16516/j.gedi.issn2095-8676.2019.02.021
Abstract:
[Introduction] With the development of cloud computing, big data, artificial intelligence, 5G, and ubiquitous Internet of Things, the data center for the power industry is to improve the planning and leading of the data center of the power industry and the full life cycle digital service capability of the system integration. Scholars and builders provide an academic exchange platform. The 2nd China Power Industry Data Center Summit Forum was held in Guangzhou on May 9, 2019. [Method] The conference was co-sponsored by the Data Center Working Group of the Information Engineering Professional Committee of the China Engineering Construction Standardization Association and the China Energy Construction Group Guangdong Electric Power Design and Research Institute Co., Ltd., and hosted by the China Institute of Intelligent Information. [Result] This forum will focus on the construction of China′s power industry data center, technology leapfrog development, industry innovation and integration; in the environment of the fourth industrial revolution led by digital, network and intelligent, co-operate with electricity Cross-border development and technology integration with data centers. [Conclusion] The conference is of great significance to promote the development of data centers in China′s power industry.
