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[Introduction] With the emphasis and promotion of the electricity market system construction by the government, the electricity market is constantly growing towards a deeper and more unified direction. In order to promote the electricity market construction, the influence factors of the electricity market risk and its evaluation remain to be studied further. [Method] Based on the consideration of the whole cycle of electricity market trading, this paper took pre-trade risk, during-trade risk, and post-trade riskas the entry points, integrated the existing risks in each stage of electricity market, and established the risk evaluation index system for electricity market. Based on the thought of subjective and objective weighting, analytic hierarchy process (AHP) and entropy weight method were used to assign weights to the index system respectively, and fuzzy comprehensive evaluation (FCE) was adopted to evaluate the comprehensive risk level of the electricity market. [Result] The rationality, comprehensiveness and validity of the proposed model are verified through the analysis of the calculation examples of different electricity markets. [Conclusion] The model eatablished in this paper can conduct a comprehensive risk evaluation for the electricity market, and provide a theoretical reference for the construction of the risk system of the electricity market and its future development direction.

[Introduction] In order to change the current patrol inspection mode of power plant mainly based on manual patrol ins-pection, improve the intelligent level of power plant patrol inspection, and fully grasp the design method of robot autonomous patrol inspection system. [Method] This paper started from the design idea of the robot autonomous patrol inspection system, defined the system functions, and gave the design scheme of the patrol inspection system from the hardware architecture and software functions. Based on this design scheme, a 5G+ robot autonomous patrol inspection system integrating progressiveness and practicality was designed. In addition, in order to make the robot's patrol inspection results more intuitively reflect the actual operation of the power plant, this paper, based on intelligent image processing technology, completed the analysis and processing of instrument readings, valves, button switch status and other information. [Result] The 5G+ robot autonomous patrol inspection system can realize map construction, task deployment, autonomous navigation and execution of patrol inspection tasks, automatic identification of patrol inspection equipment, and use 5G to return patrol inspection data, complete the analysis of patrol inspection results and automatically generate patrol inspection reports. [Conclusion] The 5G+ robot autonomous patrol inspection system in intelligent power plant developed in this paper can significantly improve the patrol inspection efficiency, improve the intelligent level of power plant operation and maintenance, provide strong technical support for the independent patrol inspection operation of the power plant, provide reliable basis for professionals to comprehensively grasp the operation status of the boiler room, steam turbine room, booster station and auxiliary workshop, and ensure the safe operation of equipment in key areas while reducing personnel and increasing efficiency, better assist the construction of smart power plants.

[Introduction] Under the current situation of increasing automation level of distribution network, in order to solve the problem that the influence of distribution automation is not considered in traditional distribution network power supply reliability assessment methods, in this paper, a method for rapid assessment of power supply reliability of urban distribution network is proposed, which takes into account the automatic partitioning of distribution network. [Method] In this paper, based on the node division method of path characteristics, by demarcating automatic partitioning of distribution network, defining large and small segments, a method for evaluating the effect of power supply reliability improvement that was suitable for automatic partitioning of distribution network was proposed. [Result] Compared with the industry standard for reliability evaluation of medium-voltage distribution network, the proposed method fully considers the influence of distribution automation on reducing fault location, isolation and switching operation time, and the evaluation result is reduced by about 22%. [Conclusion] The proposed method can more accurately analyze the power supply reliability of the distribution network with a higher level of distribution automation, and is suitable for urban distribution network areas with a small power outage time base.

[Introduction] As an important thrust of China's "new infrastructure", internet data centers have ushered in opportunities for vigorous development and become new areas of energy use, putting forward higher requirements for the power supply level and capacity of the local distribution network. The innovative application of flexible transmission and distribution technology and key equipment makes the power supply and distribution system more intelligent, more flexible and more reliable, and more able to cope with the challenges brought by the large proportion of DC loads and concentrated high-load energy loads such as Internet data centers, and realize the construction and operation of Internet data centers more low-carbon, more efficient, more reliable and more economical. [Method] Firstly, the basic load requirements of Internet data center were discussed, the overall classification and performance requirements of internet data centers were analyzed. The application of flexible technology in distribution network was studied, with a focus on analyzing and comparing three types of technical routes: "rectification distribution, DC distribution, and AC-DC hybrid power supply and distribution". [Result] The paper provides provides tailored solutions for issues related to system reliability, stability, power quality, power efficiency and acceptance of new energy. [Conclusion] By summarizing the existing research results, flexible transmission and distribution technology is regarded as the core technology of building internet data center. Targeted data center control scheme should be studied from different aspects such as device and algorithms. After summarizing the research results of different aspects, the paper also looks forward to the practice and popularization of head-to-head transmission and distribution technology in internet data center.

[Introduction] With the increasing demand for clean energy, the offshore wind power sector has seen a spurt of progress in recent years, and the bucket foundation has become the preferred choice for offshore wind turbines considering its good economy, convenient construction, and recyclability. Due to the widespread distribution of seismic zones in China, the seismic performance of bucket foundation is a crucial consideration for structural design. The bucket foundation is featured by high structure stiffness, so that the probability of structure damage caused by earthquake is low, and the failure under earthquake is mainly caused by the liquefaction of the foundation soil. For this purpose, the paper focuses on the seismic performance of bucket foundation in sandy soil. [Method] The liquefaction resistance of sandy soil for bucket foundation was analyzed by shaking table tests in this paper. The study objects included four types of bucket foundation in sandy soil, namely mono-bucket foundation (MBF), composite bucket foundation (CBF), three-bucket jacket foundation (TBJF) and four-bucket jacket foundation (FBJF). [Result] By carrying out shaking table tests, the excess pore pressure ratios of sandy soil for different types of bucket foundation under earthquake are obtained, and the impact mechanism of bucket foundation on the anti-liquefaction performance of sand soil is clarified. [Conclusion] The bucket foundation can improve the liquefaction resistance of sand, since the additional load effect of the superstructure and the hoop effect of bucket skirt weakens its shear shrinkage. The test results of MBF are compared with those of CBF, and the test results of TBJF are compared with those of FBJF. It is found that the seismic performance of CBF and FBJF is respectively superior to that of MBF and TBJF.

[Introduction] In the context of the new power system, low-carbon maintenance of wind turbines and coordinated maintenance with conventional wind turbine generator systems (WTGS) need to be solved urgently. In this paper, taking into account the impact of multi-attribute meteorological factors and low carbon and economic needs, an optimization model for wind power, hydropower and thermal power combined low-carbon maintenance based on continuous hidden Markov model is established. [Method] Firstly, dynamic tracking of wind farm maintenance capacity was realized by taking rainfall, wind speed and lightning hazard degree as the observation sequence, taking maintenance capacity as hidden state sequence, and using continuous hidden Markov model (CHMM) process. Then, an optimization model for wind power, hydropower and thermal power combined low-carbon maintenance was constructed by taking the optimal maintenance capacity as the decision-making basis, taking the minimum total cost as the optimization objective, and taking the maintenance constraints and system control constraints into consideration. Finally, took the IEEE30-node system as an example. [Result] The results show that the proposed model has more significant economic benefits and low carbon characteristics. [Conclusion] The research in this paper has high theoretical value for the operation and maintenance of WTGS, and has strong engineering applicability.

[Introduction] With the development of wind power generation technology, the unit capacity of permanent magnet wind generator is increasing, and the heating power is also increasing. The heat dissipation of generator is facing unprecedented challenges. How to effectively solve the problem of generator temperature rise and heat dissipation difficulty has been the focus of our study. [Method] Based on the STAR-CCM+ software platform, an integrated numerical simulation method for generator heat dissipation and cooling was proposed in this paper. The reliability of the numerical calculation method was verified by comparing the calculated values with the experimental values. On this basis, a study was conducted on the internal temperature distribution law and the factors influencing the cooling system heat dissipation performance of the high power permanent magnet wind generator. [Result] Under the rated power, the highest temperature of the winding and stator core appear in the middle area. If the process conditions allow, the cooling water pipe should be as close to the winding as possible to take away more heat. The stator core temperature and winding temperature can be reduced significantly by increasing the total intake air volume of the generator. The intake air temperature has a linear relationship with the maximum temperature of the winding and stator core. For every 5℃ decrease in the intake air temperature, the maximum temperature will be reduced by about 1.4℃. Reducing the intake air temperature can improve the heat dissipation performance of the generator to a certain extent. The intake water temperature has a linear relationship with the maximum temperature of the winding and stator core. For every 5℃ decrease in the intake water temperature, the maximum temperature will be reduced by about 3.3℃. Reducing the intake water temperature can greatly improve the heat dissipation performance of the generator. In addition, the gap between the cooling water pipe and the stator core greatly hinders the heat transfer of the cooling water pipe. Filling the gap with materials with good thermal conductivity can effectively improve the heat dissipation performance of the generator. [Conclusion] The conclusions drawn in this paper can effectively guide the heat dissipation design of permanent magnet wind generator and ensure the safe operation of wind turbines in normal work.

[Introduction] With the steady progress of the carbon peaking and carbon neutrality goals, more and more distributed renewable energy is connected to the power grid. Among them, in economically developed coastal areas with heavy power load, vigorously developing offshore wind power has become a hot point of wide concern for scholars at home and abroad. However, the inherent intermittency of wind power generation, especially when the offshore wind farm is actively disconnected from the main grid during typhoons, can adversely affect the receiving-end grid. [Method] In order to realize the friendly access of offshore wind power during typhoon, considering the advantages of hydrogen energy storage such as high storage efficiency, low emission and wide application, this paper proposed a collaborative control method between offshore wind farm and hydrogen management system (HMS). On the one hand, during the period of typhoon approaching, this method could maximize the use of wind energy for power generation under normal operation. On the other hand, when the typhoon passed through and the offshore wind farm was gradually disconnected from the grid, the hydrogen energy system released electric energy to alleviate the active power drop of the wind farm and solve the problems such as the ramp rate in the operation of the traditional wind turbine generator systems, so as to reduce its adverse impact on the receiving-end grid and effectively smooth the volatility of the offshore wind power output. This paper firstly introduced the physical modeling method and control model of offshore wind farm and hydrogen energy system in detail, and explained the collaborative control strategy between them according to the typhoon period. [Result] Finally, simulation results show that the proposed method enables the offshore wind farms to be more flexible and friendly to meet the grid-connected operation during typhoons. In addition, the hydrogen energy storage system can maximize the use of wind energy for power generation under normal operation. [Conclusion] Control the hydrogen energy system to release electric energy during typhoons can solve the problems such as the ramp rate of the traditional wind turbine generator systems, so as to reduce its adverse impact on the receiving-end grid.

[Introduction] The growth of wind power industry is accelerating faster than ever worldwide, at the same time, the waste generation from end-of-life wind turbine blades is expected to peak in recent years. Efficient recycling of end-of-life wind turbine blades has become a key issue affecting the sustainable development of the wind power industry and its low-carbon-footprint target. [Method] Traditionally, majority of the end-of-life blades were either buried or incinerated after being dismantled, causing resources wasting and severe environmental problems. In this context, this paper reviewed the mainstream domestic and international recycling processes of end-of-life wind turbine blades such as mechanical recycling, pyrolysis, chemical recycling and comprehensive recycling, and analyzed their corresponding advantages and disadvantages. [Result] By summarizing the industrial recycling application scenarios, this paper provides suggestions and prospects for the prospective recycling market of the end-of-life wind turbine blades. [Conclusion] Wind power industry plays an important role in realizing the "carbon-peaking and carbon-neutrality" goals through assisting in implementation of the energy-conservation and emission-reduction strategy. However, the wind turbine blade recycling market is currently in the exploratory stage with medium and small-size, there is an urgent need for policies, standards and technology development to help with its large scale industrialization. This paper illustrates current status and development trend of domestic and international recycling technology and application scenarios of end-of-life wind turbine blades, and aims to provide the scientific references for the sustainable and low-carbon development of the wind power industry.

[Introduction] In order to guarantee urban power supply and offshore wind power utilization without building new power lines, the paper aims to establish a electricity transmission strategy based on wind-coal-battery- hydrogen -CCUS multi energy coupling and bundling system, which is analyzed theoretically and verified by simulation.[Method] To verify the effectiveness of the strategy, four experimental schemes (separate transmission of wind and coal power, bundled transmission of wind and coal power without operation coupling, bundled transmission of wind and coal power with operation coupling, and wind-coal-battery-hydrogen-CCUS coupled transmission) were set up, and based on the HOMER software environment and particle swarm optimization algorithm, the system operation simulation and index calculation of the test scheme are carried out.[Result] According to the simulation results, compared with normal separate transmission strategy, power transmission line capacity of system applying wind-coal bundled transmission strategy can be decreased by 2.2 GW, with an average utilization rate of 59%, i.e. 21%~23% higher. In the case that the wind power and coal power share the same transmission line without coordinated operation, the wind power curtailment is 164 GWh in total. System applying wind-coal-battery–hydrogen-CCUS bundled transmission strategy could avoid wind power curtailment and reduce carbon emission from unit power supply by about 30~33g/MWh. [Conclusion] In conclusion, the electricity transmission strategy established by this paper is supposed to be feasible and effective and contributing to planning and construction of offshore wind power project.

[Introduction] Hydrogen energy is characterized by the advantages of wide sources, high calorific value, storability, no pollution, and zero carbon emissions. It has become a zero-carbon clean energy with great development potential. At present, mature hydrogen production technologies are mostly based on large-scale hydrogen production, which can hardly meet the demand for compact portable hydrogen production equipment in some important occasions. [Method] In order to meet this demand, this paper first analyzed and summarized the characteristics, advantages and disadvantages, and development trends of the existing large-scale hydrogen production technologies. Besides, considering that ammonia has the advantages of easy liquefaction and storage and high hydrogen content and is an excellent carrier for hydrogen, this paper further proposed the technical idea of using porous medium burner with adiabatic flame temperature to produce hydrogen by ammonia reformation and carried out a systematic analysis from the aspects of technical feasibility, research methods and research contents. [Result] Based on the existing research results of porous medium burners, the feasibility of using porous medium burner for ammonia reforming to produce hydrogen is analyzed. On this basis, the research methods, research contents and technical routes of ammonia reforming for hydrogen production by using porous medium burner are summarized and prospected. [Conclusion] Obtaining the optimal design for the overall structure, microchannel, and reaction carrier structure of the porous medium burner and developing non-precious metal catalyst materials with good performance and low cost will be the main research directions of the porous medium burner for hydrogen production by ammonia reforming. The research in this paper can provide some theoretical and technical support for the development of the technology of hydrogen production by ammonia reforming with porous medium burner.

[Introduction] In order to improve the problem of traditional proportion integration differentiation (PID) controllers overly relying on the mathematical model of the controlled object in the temperature control in hydrogen production by water electrolysis, this paper studies the application of fuzzy internal model control in the temperature control in hydrogen production by water electrolysis, and provides the design process of the fuzzy internal model controller. [Method] Firstly, the importance of temperature in the process of hydrogen production by water electrolysis was analyzed, and some temperature control strategies commonly used in hydrogen production by water electrolysis and their advantages and disadvantages were listed. Then, internal model control theory and fuzzy theory were introduced, and a design method for a fuzzy internal model temperature controller, which was used to achieve precise temperature control in hydrogen production by water electrolysis, was proposed based on these two theories. Finally, simulation verification experiments were conducted. [Result] The results show that the fuzzy internal model control method used in this paper has better control quality in response speed, anti-interference, and robustness compared to the PID control method, solving the problem of traditional PID controller algorithms overly relying on the mathematical model of the controlled object. [Conclusion] The control algorithms used in this paper are correct and effective, and can be applied to the temperature control in hydrogen production by water electrolysis.

[Introduction] As wind-solar hydrogen production projects expand in scale and number, there is a growing demand for the design, equipment selection, and economic comparison of green hydrogen production systems. This paper, based on the design experience of multiple similar projects, extracts the typical design of wind-solar coupled hydrogen production system and provides the design selection. [Method] This paper introduced design scheme of wind-solar coupled hydrogen production from the aspects of wind-solar hydrogen storage capacity configuration scheme, electrolysis hydrogen production equipment performance and rectifier comparison, hydrogen and oxygen separation and purification system design, and green hydrogen market and economy analysis. [Result] Capacity configuration can be optimized according to the developed design software through constraint conditions. alkaline electrolysis equipment is the preferred choice for hydrogen production，while proton exchange membrane (PEM) electrolysis equipment can be used for small-scale engineering demonstration. Both thyristor and insulated gate bipolar transistor (IGBT) power rectifiers have their own advantages, and IGBT rectification is gradually being applied in engineering practice. For saving investment, separation and purification can be optimized according to the scale of the project. The market for green hydrogen is huge. As fossil fuel prices continue to rise and the costs of wind-solar coupled hydrogen production systems decrease, coupled with its eco-friendly characteristics, green hydrogen has already become economically competitive. [Conclusion] The wind-solar coupled hydrogen production project is still in the initial demonstration stage, which requires equipment technology progress, design scheme optimization and government policy support to promote the development of green hydrogen industry.

[Introduction] The increasingly high proportion of renewable power sources raises higher requirements for the safe and stable operation of the power system and the reliable supply of electricity. Hydrogen and electricity are complementary in many scenarios of energy consumption. Green hydrogen produced by renewable power will become an important component of the new energy system, which can also facilitate the construction of the new power system. Recently, green hydrogen demonstration projects in China and abroad are burgeoning. However, the typical modes and future development trends are not clear. This paper aims at clarifying the typical modes for green hydrogen projects and providing solutions to issues faced by the large-scale application and the full play of power-hydrogen coupling. [Method] In this paper, the existing green hydrogen demonstration projects in China and abroad were systematically analyzed. The characteristics of the three groups were studied, based on which, the development trends of green hydrogen demonstration projects were proposed. Then, the key problems and challenges were analyzed, and key measures were proposed. [Result] Through the study, the green hydrogen projects are grouped into three categories, which are power-hydrogen coupling projects on the distribution/micro-grid side, large-scale hydrogen production near renewable basis and utilization projects and hydrogen-based flexible adjustment projects. Key issues lying ahead include the lack of coordinated planning between the power and hydrogen system, the less economic competitiveness of green hydrogen and some of the key technologies, equipment and materials are dependent on imports. [Conclusion] To solve these issues and promote the development of green hydrogen projects, the coordinated planning of power and hydrogen system should be strengthened, formulated a set of supporting policies, improved the relevant market mechanisms, accelerated the standards and deployed some essential projects.

[Introduction] Hydrogen energy plays an important role in the construction of a new energy system due to its extensive sources, convenient storage and transportation, and efficient utilization. This paper systematically analyzes the development strategies of the hydrogen energy industry in the United States and European Union, and combines with the actual development of Chinese industry, and gives specific policy suggestions for the development of the hydrogen energy industry. [Method] The successful experience of hydrogen industry development in the United States and Europe was summarized by combing and analyzing the relevant policies, strategic planning and typical practices of hydrogen energy development in the two major economies. [Result] Based on the current development status of the hydrogen energy industry in our country, this paper puts forward a number of targeted policy recommendations, including strengthening the top-level design to further improve the hydrogen energy industry development policy system; strengthening the guidance of scientific and technological innovation, and attaching importance to the innovation and breakthrough of core technologies in key links of hydrogen energy; expanding the diversified application of hydrogen energy and building a collaborative ecology; attaching importance to international cooperation and taking an active part in the formulation of international rules and standards. [Conclusion] The policy recommendations mentioned in the article can provide reference for relevant departments and industries, so as to further improve the development quality and speed of the hydrogen energy industry.

[Introduction] The paper proposes an energy consumption calculation method for prefabricated cabin type lithium iron phosphate battery energy storage power station based on the energy loss sources and the detailed classification of equipment attributes in the station. [Method] From the perspective of an energy storage power station, this paper discussed the main factors to be considered in the energy consumption calculation of prefabricated cabin type lithium iron phosphate battery energy storage power station, and then divided the energy consumption of the energy storage power station into two parts, namely, the energy consumption of the energy storage system and the energy consumption of the auxiliary equipment operation. Besides, it also provided the calculation method for the energy consumption of each part and the selection method of efficiency value respectively. [Result] Through a practical calculation example, the whole-day energy consumption of a 2 MW/2 MWh energy storage battery prefabrication cabin in a certain operation mode is analyzed and compared with the field test results. The difference between the field test results and the theoretical analysis results is analyzed from the perspective of the heat produced by the energy storage battery and the heat transmitted by the air conditioner, and suggestions are put forward for the energy consumption statistics of the energy storage power station. [Conclusion] The energy consumption calculation method proposed in the study comprehensively discusses the main factors affecting the energy consumption index of the prefabricated cabin type lithium iron phosphate battery energy storage power station and gives the energy consumption calculation method for the main equipment according to the detailed classification of equipment attributes, which has a good engineering reference value.

[Introduction] The research and development of offshore floating photovoltaic complies with the needs of national energy strategic development, caters to the background of industry development led by science and technology, and helps the development of emerging economic industrial chain. This paper aims to deeply explore the main components and core technologies of offshore floating photovoltaic system, and provide a theoretical basis for the development of offshore floating photovoltaic in China. [Method] Based on the existing research on offshore floating photovoltaic at home and abroad, this paper refined the relevant construction technology of flexible photovoltaic, verified the commercial feasibility of offshore floating photovoltaic development, introduced the configuration and composition of large-scale offshore floating photovoltaic (LOFPV) system, expounded the hydrodynamic design theory and method basis of flexible membrane structure and mooring system, and showed the typical engineering practice of offshore floating photovoltaic. [Result] Offshore flexible membrane-based floating photovoltaic has many advantages, such as lightweight, miniaturization, high power exchange efficiency and flexible configuration. In addition, the membrane structure is foldable, convenient for transportation, and convenient for installation, and the overall structure has no complex connector, so the system has high reliability and is convenient for operation and maintenance. Relevant achievements of this paper will provide great reference value for the development of China's offshore floating photovoltaic technology. [Conclusion] The functionality and reliability of flexible membrane-based floating photovoltaic construction technology are explained, and this flexible membrane structure will definitely be an important application type of offshore floating photovoltaic in the future.

[Introduction] The strategic goal of "carbon peaking and carbon neutrality" has increased the demand for new energy power grid integration, so it is necessary to improve the flexible operation capacity of coal-fired generating units. [Method] This paper introduced the flexible transformation technology and common evaluation indicators of existing coal-fired units in detail. Flexibility transformation mainly included condensate throttling technology, coupled biomass co-combustion transformation technology of coal-fired units, flexibility technology of pulverizing system of coal-fired units, etc.; Common evaluation indicators for the flexibility of coal-fired generating units included: the power consumption rate of the generator set plant, the thermal efficiency of the boiler, the standard coal consumption rate of the generator set, etc. On this basis, this paper summarized and analyzed the flexibility transformation technology and evaluation indexes. [Result] Finally, the paper puts forward seven kinds of the technology development direction and relevant suggestions of coal-fired generating units. [Conclusion] The structural improvement of original generating units, the introduction of multi-form new energies and the coordinated regulation design of multi-heat storage will be the main direction of subsequent development. It is expected that paper can provide reference for subsequent coal-fired generating units to adapt to "dual carbon" energy planning.

[Introduction] With the development of Marine economy, more and more projects of offshore wind power transmission, offshore oil and gas platform power supply and island network power supply involve laying submarine cables. At present, the main laying protection method is direct burial laying, but the buried depth design without considering the economy is obviously unreasonable. In order to effectively protect the submarine cable and reasonably control the investment, it is necessary to determine the reasonable burial depth of the submarine cable in the project development stage. Therefore, in the absence of sufficient design input data, this paper proposes a simplified calculation method for the depth of anchor penetration, which provides a basis for determining the laying protection scheme in the early stage of the project. [Method] In this paper, the anchor penetration process was divided into three stages to establish mathematical models, and a series of boundary conditions were assumed for the anchor penetration process. On this basis, based on the energy method, we analyzed and deduced the mechanical model of the anchor movement process at each stage, and proposed a simplified calculation method of the anchor penetration depth considering the shear damage of the seabed substrate. By conducting a comparative analysis of the calculated values of the method and measured values under different situations, we explored the applicability and scope of the calculation method. [Result] The comparison between the calculated value of this simplified method and the measured result shows that this calculation method is suitable for calculating the depth of anchor penetration in the case of clay with shear strength greater than 20 kPa, and the calculation error of this method is within the acceptable range. [Conclusion] From the comparative analysis of the calculation results in this paper, it can be seen that the simplified calculation method has guiding significance for the application in engineering practice, but the method still needs to accumulate different measured data in practice for verification and fitting correction, and combine the empirical method and probabilistic method for further analyses, to provide design basis for submarine cable laying protection.

[Introduction] In order to solve the prominent contradiction between electric load and heat load faced by coal-fired units and ensure the heat source supply of units in winter, it is necessary to study the heating transformation scheme to break its thermoelectric coupling relationship. [Method] This paper made a model analysis of two heating transformation modes of a type of 300 MW coal-fired unit, compared the heating capacity and other data before and after the unit transformation, and studied the thermoelectric decoupling heating transformation scheme in line with the production conditions. And the economic effect of heating transformation of cogeneration units was summarized. [Conclusion] Through the analysis of the heating model in this paper, it can be seen that the coal-fired unit only relies on steam extraction for heating, which is greatly restricted by the power load. The heating capacity at high power load is 2～3 times that at low power load. When the electric load is severely limited, its heating capacity cannot meet the heating demand in winter. But after retrofit of high back pressure and modification of the cylinder, the capacity of peak shaving increases, and the heating capacity increases to 3～4 times under the same electric load, which effectively solved the problem. [Result] The research result can be used as a reference for the heating transformation of the same type of coal-fired units in the future.

[Introduction] The goal of "carbon peak and neutrality" will require profound changes in the existing energy structure. Improving the flexible adjustment capabilities of the original coal-fired cogeneration units is one of the essential elements in ensuring the safe grid connection of new energy power. [Method] This paper reviewed the flexible adjustment requirements of the coal-fired cogeneration system, the current status of potential energy storage applications, and the development direction of coupled energy storage technology. [Result] It is concluded that the deep "thermoelectric decoupling" is still the key to improving the coal-burning cogeneration system. Secondly, to meet the "source-charge" matching, energy storage technology will play an essential role in the coal-fired cogeneration system, among which energy storage technology with potential application mainly includes heat storage, electricity storage, and flywheel energy storage. [Conclusion] Finally, according to the application characteristics of coupled energy storage technology for coal-fired cogeneration units, the paper puts forward suggestions on the aging of energy storage performance, absorption of new energy, long-term change of thermal power load in the expansion area, economic analysis of initial investment, and payback period and relevant issues needing attention.

[Introduction] The proposal of the "carbon peak and neutrality" goal increases the necessity of new energy power embedding. To study the method to improve the flexibility of the unit, this paper introduces the flywheel energy storage technology and the related research of the coupled generator set in detail. [Method] The working principle, research status, and achievements of flywheel energy storage as well as application difficulties and measures were summarized, and the specific methods of studying the system modeling and operation strategy of flywheel energy storage were analyzed, and the principle and application characteristics of flywheel energy storage coupled with thermal power generation, wind power generation and solar power generation were analyzed emphatically. [Result] This paper shows that the research on flywheel energy storage systems in China has achieved relatively advanced results and formed a set of effective research methods, and some research has been done on the coupling of flywheel energy storage technology with multi-energy generator set. [Conclusion] In today's environment, flywheel energy storage technology coupled with multi-energy generators has become a research trend and focus, the summary of this paper provides a reference for the subsequent application of flywheel energy storage technology.

[Introduction] China Fusion Engineering Experimental Reactror （CFETR） aims to demonstrate the engineering feasibility of steady-state combustion plasma. The 110 kV high-voltage power supply and distribution system supplies the superconducting magnet and the reactive power system through cables and other equipment. Therefore, the stable work of the high-voltage cable is very important to the development of the experiment. [Method] The normal operation of the cable needed to consider the induced potential and circulating current of the metal sheath. In this paper, after fully investigating and calculating the metal sheathing method, it was determined that the 110 kV high-voltage XLPE cable was cross-connected and grounded. Use ANSYS Maxwell to model the three-phase cable, simulate the sheath induced voltage, and finally substitute the simulation results into the equivalent circuit constructed by Simplorer. [Result] The simulation results show that the induced electric potential and circulating current of the sheath meet the requirements of national standards. [Conclusion] The cross interconnection grounding scheme designed in this paper for the 110 kV cable sheath is safe and reliable, which can ensure the long-term stable operation of the cable.

[Introduction] The paper aims to effectively suppress the disturbance of non characteristic harmonics to the power grid in the tokamak power supply system, the paper studies the mechanism of low-frequency harmonics in the tokamak power supply system. [Method] By introducing an improved switching function model, selected ITER fusion device as an example and established its corresponding AC/DC equivalent circuit model combined with its corresponding parameters, the corresponding output second harmonic was obtained through calculation and simulation. [Result] The ratio of output to input is calculated, and the stability factor value almost tends to zero. [Conclusion] It is determined that the DC bias of rectifier transformer do not cause harmonic instability of the system.

[Introduction] The paper aims to research the technology feasibility of steam conversion system for industrial steam supply by pressurized water reactor (PWR) nuclear power. [Method] we took a 1 000 MW (PWR) nuclear power plant as an example, supplying industrial steam 300 t/h, 1.8 MPa and 250 ℃. This paper demonstrated the technical feasibility of a steam conversion system which could meet the industrial steam needs by using steam in the secondary loop of PWR nuclear power plant to heat industrial water, based on the first law and the second law of thermodynamics. This paper designed the process flow of the system, calculated the thermodynamic parameters of the key heat exchangers in the system. [Result] The reasonable value of the heat source drainage temperature was analyzed. Our data suggest heat source drainage temperature is 65 ℃ for the industrial steam supply of PWR nuclear power plants. The temperature of heat source would be lower than the industrial water if the drainage temperature was lower than 60 ℃ ，which would violate the second law of thermodynamics. [Conclusion] The research results can provide technical reference for industrial steam supply of PWR nuclear power plant.

[Introduction] In order to guide Guangdong power grid to carry out digital construction in an orderly manner during the 14th Five Year Plan period, realizing the digital sustainable development of Guangdong power grid, and effectively support the implementation of the development strategy of Guangdong Power Grid Corporation, this paper puts forward the methods of digital planning of power grid enterprises and suggestive digital development ideas. [Method] To ensure the planning methods and thought in compliance with the actual development of grid enterprises, the paper proposed persisting in the strategy-oriented planning thought, taking hold in actual conditions and innovation drive, and under the overall operation strategy of grid enterprises considering the business development needs as a whole to develop a general strategy of digitalization, which was planned exclusively and implemented step by step, i.e.to decide digital strategy planning by corporate development strategy, and decide digital technology structure by digital strategy planning. [Result] According to this method, the pain points of power grid business and the defects and deficiencies of digital construction of power grid enterprises are analyzed, the power and demand of digital development of power grid enterprises are analyzed, the digital development objectives and paths of power grid enterprises are put forward, the digital development blueprint of power grid enterprises is designed, and the application architecture and technical architecture are put forward. [Conclusion] The proposed digital development planning idea of power grid enterprises is scientific and feasible, and can provide guidance for the digital construction of Guangdong Power Grid Corporation in the 14th Five Year Plan.

[Introduction] The result of tower foundation configuration directly affects the accuracy and rationality of the foundation scheme. The problem of slow manual configuration speed and low accuracy of tower height-low leg need to be solved. [Method] This paper analyzed the configuration process and configuration result,and then this paper put forward the problems in the manual configuration process. The accuracy of manual configuration was low, especially for towers with steep terrain or large slope ratio. The manual configuration results may affected the safety of foundation or caused the foundation design parmeters to be conservative. Through the problem analysis of the conventional configuration process, a reverse configuration method and a 3D configuration program were put forward in this paper. [Result] The reverse configuration method is used to configure the same tower, and the result of the reverse configuration method is accurate, which can quickly and accurately calculate the various parameters and accurately calculate the actual exposed height. [Conclusion] The accuracy and efficiency of reverse configuration method are better than that of manual configuration, and the configuration results are intuitive and accurate. It is recommended to use the method to configure the high-low leg in engineering.

[Introduction] In the process of accelerating the construction of new power system with new energy as the main body, giving full play to the leverage effect of venture capital is conducive to promoting the rapid formation of scale economic advantages of new energy power generation, and promoting the achievement transformation and industrial implementation of new energy strategic emerging industries. [Method] Therefore, the theory of venture capital and risk management was introduced into the practice of new energy development and construction, and the related theories of strategic management, venture capital and new energy development and construction were integrated to construct the whole cycle risk management index system of new energy venture capital in this paper. The four elements of risk management and their work contents were put forward, a closed-loop risk management was formed, and the macro and micro elements were comprehensively considered, then the index system of risk identification and evaluation and its quantitative weight were designed from the aspects of industry policy, market environment, competitors and the economic benefits of the project itself, and the content, process and interface of risk report and control were defined. [Result] The practicality of new energy venture capital is enhanced. [Conclusion] The research results of this paper can provide operational reference for the introduction of venture capital and effective risk control in the new energy industry.

[Introduction] With the accelerated evolution of the national energy structure, offshore wind power will enter a period of rapid and stable development. At present, the development of offshore wind power near the shore of many provinces in China is nearly completed, and the offshore wind power is gradually developed to the offshore deep water area and will expand to a large scale. Offshore wind power in deep water areas has higher technical requirements for marine geotechnical investigation, and marine geotechnical investigation vessels and equipment need to be professional. But the number of large scale professional marine geotechnical investigation platforms in China is limited and they mainly serve the national marine resource exploration and scientific research work. They are rarely used for offshore wind power geotechnical investigation and the investigation costs are high. The traditional investigation mode of modified marine engineering (cargo) vessels with conventional drilling equipment is no longer suitable for offshore deep water area, nor for marine investigation operations in the short window period. Therefore, it is necessary to conduct in-depth research on the technology of marine geotechnical investigation platform. [Method] Through the research on the domestic marine geotechnical investigation vessel platform and exploration equipment, a comprehensive comparative analysis was carried out on their applicable water depth, ability to resist wind and wave, operation efficiency and investigation quality. According to the geotechnical investigation characteristics of offshore wind power and the sea condition of its development and utilization, the construction ideas and schemes of offshore geotechnical investigation platform for offshore wind power in deep water areas were proposed. [Result] The investigation practice of several offshore wind power projects has proved that the construction scheme of marine geotechnical investigation platform proposed in this paper can be applied to offshore deep water area operation, and can make full use of the 24-48 hour window period of marine investigation. [Conclusion] The scheme proposed in this paper is reasonable, which can effectively improve investigation efficiency, ensure the investigation progress and reduce investigation costs.

[Introduction] The solenoid pressurizer spray valve is one of the key valves for PWR nuclear power plant, and it is of great significance for nuclear power construction to realize the independent research and development of the valve. [Method] In this paper, Starting from the system functional requirements and technical parameter requirements of the solenoid pressurizer spray valve, the overall structure, proportional solenoid, middle thermal protection device, valve position detect and output device, control system with pilot disc of the independently-developed solenoid pressurizer spray valve were briefly introduced in this paper. [Result] Through this independent research and development, the design technology of the solenoid pressurizer spray valve is mastered, the technical difficulties of the electromagnetic drive structure and the adaptability of the valve working under high temperature and high pressure medium conditions are solved, the system functional requirement for pressurizer spray valve is realized. [Conclusion] The independently-developed solenoid pressurizer spray valve meets the development needs for third generation nuclear power plant, and can be popularized and applied.

[Introduction] With the proposal of "peak carbon dioxide emission, carbon neutrality" and the deepening of energy reform, hydrogen energy, hydrogen energy as an important industrial raw material and energy fuel has been widely concerned and entered a rapid development period. Hydrogen energy industry chain mainly includes the hydrogen preparation, storage, transportation and utilization, which involves the integration and technological innovation of many industries. This paper is aimed at sorting out the current situation of hydrogen energy industry chain and analyzing the challenge faced by each node in order to provide suggestions for the development of hydrogen energy industry in the future. [Method] In this paper, we investigated the current technical status, analyzed the problems and challenges of the hydrogen energy industry chain, and put forward the relevant suggestions. [Result] Although China has technical reserves and industrial layout in all aspects of hydrogen energy industry, many technical shortcomings need to be solved. Among them, alkaline water electrolysis technology, high-pressure hydrogen storage technology, natural gas pipeline mixing hydrogen transportation technology has preliminarily met the application conditions. However, some problems in the technologies such as low temperature liquid hydrogen technology, hydrogen manufacturing with proton exchange membrane and fuel cell technology, hydrogen manufacturing with solid oxides and fuel cell technology remain to be solved. Meanwhile, compared with international advanced level, the development of hydrogen-fueled gas turbine in China is relatively backward. [Conclusion] As a strategic energy, the utilization of hydrogen energy is very important to promote the green transformation of energy and industry. But there are still many problems. Hence, it is necessary to make a reasonable layout, avoid the repetitive construction and introduction of low-end technology to accelerate the development of hydrogen energy industry.

[Introduction] In order to determine soil strength parameters more accurately and reliably, based on domestic and foreign engineering experience and research results, this paper proposes a practical method to obtain the undrained shear strength of clay and the friction angle of sand based on static cone pentration test (CPT) and standard penetration test (SPT) data. [Method] Firstly, it introduced the method of rapid stratification based on the four basic data of CPT, aiming to divide the sand layer and clay laye. Then the method of calculating the empirical coefficient Nkt of the undrained shear strength of clay based on the CPT parameters was introduced. Finally, a method of comprehensively considering CPT and standard penetration data and calculating the internal friction angle of sand based on empirical methods was introduced. [Rseult] According to the method of CPT parameter estimation, the obtained clay undrained shear strength is well compared with the laboratory test results which can obtain the clay undrained shear strength profile. The combined method of CPT and SPT can measure the friction angle of sand reliably, which fills the gaps of test data due to the difficulty in obtaining sand samples from offshore exploration. [Conclusion] The method discussed in this paper can provide more reliable reference for determining th design values of soil strength considering the existing condition in which offshore survey methods are limited and the equipment resources are relatively scarce.

[Introduction] Large capacity wind turbines and 66 kV power collection system will be selected for deep sea large-scale offshore wind power transmission. The wind turbines can be directly connected to the offshore converter station, so the offshore booster station can be cancelled and the intensive design can be realized. In this paper, the key electrical technology of intensive offshore converter station was preliminarily studied. [Method] On the basis of the existing offshore wind power flexible DC transmission technology, by studying the main circuit topology, core electrical equipment selection and platform layout optimization of the intensive offshore converter station, a feasible technical scheme for the key electrical technology was given. [Result] With the gradual popularization of offshore wind power 66 kV collection system, intensive offshore wind power flexible direct transmission will become the mainstream design scheme in the future. In this paper, the research conclusions with guiding significance were given for the key electrical technology points of intensive offshore converter station. [Conclusion] Compared with the traditional converter station, the intensive offshore converter station has obvious technical advantages. The research conclusions formed in this paper can provide technical support for the scheme decision-making and implementation of deep sea large-scale offshore wind power transmission project in the future, and have a good demonstration application prospect.

[Introduction] Trenchless horizontal directional drilling is widely used in power cable line project to cross natural or artificial obstacles at present.Multiple cable protection tubes need to be laid successfully at one time in engineering applications. It is defined as multiple pipelines pulling crossing, and it is widely used because of it's excellent economic and environmental protection advantages. However, there is only the calculation method of single pipe pullback force of plastic pipe at present. This paper aims to study the calculation method of pullback force of multiple pipelines. [Method] This paper was based on a 220 kV cable line project in the Pearl River Delta. This project used horizontal directional drilling to cross the national first-class waterway for twice at the same place, and most of the crossing stratum was plastic clay layer. The calculation method of single pipe pullback force was used for analysis in the project, and the change curve of pull back force was measured on site during the implementation. [Result] The comparative analysis between theoretical calculation and measured results shows that: under the condition of plastic clay layer, the measured pullback force of multiple pipelines is 4～6 times that of single pipe with the same weight and envelope diameter. The straight-line pullback of pipelines is very important to reduce the pullback force and implementation risk. [Conclusion] In this paper, the concept of multiple pipelines pulling and the calculation reference value of pulling force in trenchless horizontal directional drilling crossing project can provide a reference for the crossing design and construction of similar projects in the future.

[Introduction] With the advancement of clean energy transformation and power marketization reform, the policy mechanism and market environment of electricity energy storage in the southern region have gone into a good situation constantly. [Method] This paper studied the electric auxiliary service market and demand response market rules related to the energy storage in the southern region, analyzed the development trend of the energy storage market in the southern region from the four aspects of the auxiliary service transaction varieties, user-side demand response, new energy distribution energy and independent energy storage stations, etc. We used the user-side energy storage investment operation economy as an example to perform the quantitative analysis. [Result] The research shows that under the competitive conditions of the power marketing market, the greater the demand for frequency modulation, peak shaving, and the lack of flexible resources adjustment, the greater the contribution of energy storage to auxiliary services or demand response to the system, so as the comprehensive benefits. [Conclusion] This paper can provide ideas for power energy storage business model innovation and application promotion.

[Introduction] Through the technical and economic comparison of two ways of chemical dosing liquid ammonia and ammonia water for a large-scale combined cycle power plant in Guangdong Province, it is proposed that the water quality control index of condensate and feed water in the way of adding liquid ammonia is prior to the way of adding ammonia water. In addition, adding liquid ammonia can improve the corrosion resistance of the thermal system equipment and pipelines, and is beneficial to the safe and stable operation of the whole unit. Moreover, the consumption and operation cost of liquid ammonia are lower and the technical and economic benefits are more effective. [Method] In order to ensure the safe operation of liquid ammonia storage tank and prevent safe accidents, combined with the current national and local regulations and standards, this paper provided the safety technology design and measures for liquid ammonia system. [Result] This paper summarizes the key technology and innovative points of safety design for liquid ammonia system. [Conclusion] Therefore, it can play a reference role for the design of similar projects in the future.

[Introduction] In order to find an economic and effective solution to the improvement of the hydrodynamic performance of floating offshore wind turbines, this paper studies the design scheme of heave plates to improve the hydrodynamic damping performance and anti-rolling effect of the floating body, and finally improve the stability of the output power of floating offshore wind turbines. [Method] Taking a 10 MW semi-submersible floating wind turbine as an example, this paper discussed the effect of different design parameters of the heave plate structure on improving the hydrodynamic damping using the method of computational fluid dynamics, and found an optimal design scheme. [Result] After optimized design, the heave damping of the heave plate structure is increased by 14.9%, and the roll damping is increased by 19.1%, and while the heave damping of the “quincunx-shaped” edge heave plate is increased by 36.98% compared with the original model. [Conclusion] This paper reveals the formation mechanism of the generation of vortex vents and the improvement of the hydrodynamic damping of the heave plate, and puts forward the “quincunx-shaped” heave plate structure in an innovative manner that can effectively improve the damping performance of the heave motion of the floating body. The above conclusions provide important references for the research and design of the foundation structure of the floating offshore wind turbines of this kind in the future.

[Introduction] The purpose of this paper is to research and analyze the influence of water resources on the development of the green hydrogen industry in China, reveal the contradiction between water resources and the development of green hydrogen industry, analyze the future development trend of the green hydrogen industry and to provide useful reference for the development layout of renewable energy hydrogen production projects in China. [Method] In order to prove that water resources could limit the development of the green hydrogen industry in "Northeast China, North China, Northwest China" and other areas, the analysis and the demonstration were made based on the field investigations and the documentary materials, considering water resources policies, water usage in traditional chemical industries, and hydrogen production technologies. [Result] The analysis results show that under the restriction of China's water resources-related policies, the layout of green hydrogen industry should consider the constraints of water resources, and the large-scale production of green hydrogen and its substitution for fossil energy hydrogen production cannot effectively save water. Instead, it may lead to an increase in water consumption by the chemical industry. Under the constraint of water resources, the development of China's green hydrogen industry must consider the layout from a holistic perspective, fully integrate the development trend of the existing chemical industry, and consider the abundant resources available such as seawater. [Conclusion] The development of the green hydrogen industry in China should not ignore the problems of existing policy framework, technology level, industrial layout and characteristics of existing resources. When arranging the layout of the green hydrogen projects, the current situation and future trends should be fully considered, and the problems posed by water resources on the green hydrogen industry should be solved from the perspective of the overall planning, the coordinated industrial development and the effective utilization of resources.

[Introduction] In order to reduce frequency disturbance caused by photovoltaic (PV) generation to power grid and further improve the frequency modulation effect, an optimization strategy for collaborative frequency modulation of PVs-ESs based on MPC (Model Predictive Control) is proposed. The basic principles, control flow, constraints, target function and weight coefficient of the strategy are analyzed. [Method] A model of optical-storage network based on MPC was constructed and the nonlinear state space equation was derived. In order to verify the frequency modulation effect of this strategy, four different simulation environments were set up: no energy storage, battery storage, mixed energy storage and the strategy proposed in this paper. [Result] Simulation results show that compared with other scenarios, the proposed strategy is optimal in terms of frequency modulation and the worst in the absence of energy storage. In addition, the hybrid energy storage method is superior to the battery energy storage method. [Conclusion] The effectiveness of the proposed strategy is validated on the MATLLAB/Simulink platform. In photovoltaic power generation system, optimal control of energy storage and PV maximum power point tracking can make the grid frequency more stable and improve the stability of the whole system. The results of this study can be used as a reference for PV connection.

[Introduction] Energy storage technology becomes an essential supporting technology to build a new power system with renewable energy as the main power source. Liquid air energy storage (LAES) is one of the emerging large-scale energy storage solutions, which is technically and economically feasible and has a wide range of application prospects. The pilot plant built by Highview Power is the only LAES for which test data have been made public. The paper aims to explore the thermodynamic principle of LAES and seek ways to improve the cycle efficiency of LAES. [Method] A thermodynamic model was established according to the process flow of Highview Power's pilot plant. The thermodynamic model was verified by the test data of the pilot plant. Exergy analysis was carried out. The influence of key operating parameters on the charging and discharging process was studied by the control variable method. [Result] The results show that the key equipment limiting the cycle efficiency are recycle compressor and evaporator. Increasing the compression pressure and post-throttling pressure, increasing the mass flow rate and inlet temperature of the cryogenic expander, and recovering the cooling capacity of the regenerator are beneficial to improving the liquefaction rate and reducing the energy consumption of liquefaction. Moreover, increasing the high pressure and the inlet temperature of turbine expansion unit can help to improve the output power and cycle efficiency of LAES. [Conclusion] Some improvement measures are put forward to improve cycle efficiency, such as recovery of compression heat, improvement of compressor isentropic efficiency and reduction of heat transfer temperature difference of evaporator.

[Introduction] Lithium-ion battery has become the most widely used new energy storage technology. However, it is found that the practical service conditions have great impacts on the actual service behaviors of lithium-ion battery energy storage. This paper aims to study the influence of service conditions on the electrochemical performance of lithium-ion battery, so as to provide references for the construction of future lithium-ion battery energy storage projects. [Method] The effects of operating charge interval, discharge rate and operating temperature on the actual performance of Li-ion battery were tested and analyzed. [Result] The working SOC range, charge/discharge rage and operating temperature all have great influence on the actual performance of lithium-ion battery. On the one hand, proper adjustment of charge and discharge range can significantly improve the service life. On the other hand, the current commonly used 2 C configuration mode may significantly reduce the service life, while reducing the rete configuration to 1 C is expected to achieve lower levelized cost of energy although it will increase the initial investment. In addition, temperature control is extremely important to the usage of lithium-ion batteries, even single-digit temperature differences can cause significant battery inconformity over long cycle life. [Conclusion] Lithium-ion battery energy storage with advantages of fast response speed, high adjustment accuracy and flexible configuration will further play an important role in the work of "carbon peak and neutrality" and the gradual construction of the power market. Paying attention to the influence of practical conditions on the performance of lithium-ion battery will further improve the use efficiency of lithium-ion battery energy storage. In summary, the design of the battery working condition according to the demand of the practical application can provide lithium-ion battery energy storage system more excellent performance, and play an important role to realize the "carbon peak and neutrality" goal of our country.

[Introduction] As one of the main tracks of hydrogen energy development, fuel cell vehicle industry plays a key role in the process of transportation decarbonization. In view of the current policy environment and industrial base, it is necessary to systematically analyze the development trend and challenges of China's fuel cell vehicle market. [Method] A comprehensive discussion of the fuel cell vehicle market focusing on the market factors such as market size, segmentation direction, equipment and hydrogen source price, etc. was provided in this paper. [Result] The promotion and application effect of China's fuel cell vehicle market is closely related to the strength of policy support, the clarity of the detailed rules of subsidies and the driving force of local advantageous enterprises. In terms of market distribution, it has shown a certain leader effect according to the comprehensive competitiveness of vehicle and fuel cell enterprises. The price of the vehicle and the fuel cell power system has decreased by 5%~20% compared to 2021, but it still costs a lot in application. [Conclusion] Although China's fuel cell vehicle marketization is still hampered by the high manufacturing cost and hydrogen price, and the lack of infrastructures, but the fuel cell vehicle industry will show great vitality after further developed in performance verification, infrastructure construction and business structure innovation.

[Introduction] In order to fully implement the national policies on water resource development and utilization, embody the water-saving policies on water resource reuse, more and more industrial water source supplied to power plants in south China is reclaimed water, so it is necessary to discuss the schematic design of advanced treatment for reclaimed water. [Method] Taking a power plant in Guangdong province as an example, this paper designed the most suitable advanced treatment for reclaimed water by analyzing the treatment process of wastewater treatment plant, water quality indicators of reclaimed water and industrial water quality requirements of power plant. [Result] Adopting the scheme of "contact flocculation inclined plate sedimentation tank + filter tank", the system process was simple, the investment and operation cost were low, and the system can guarantee the safe and reliable operation. [Conclusion] This paper aimed to provide a reference scheme for the advanced treatment system design of reclaimed water in similar water source power plants in the future.

[Introduction] The power of offshore oilfield group mainly comes from generating units, which has problems of poor power supply reliability, low power generation efficiency, high pressure of energy saving and emission reduction, etc. [Method] According to the function orientation and working principle, the offshore step-down substation could be divided into six areas: 220 kV switchgear area, transformer area, 35 kV switchgear area, 10 kV switchgear area, reactive power compensation area and auxiliary room. The recommended layout plan was given through the study of each area. [Result] The layout plan proposed in this paper plays an important role in improving the reliability of offshore step-down substation, ensuring the convenience of equipment maintenance and service, and minimizing the platform size. [Conclusion] The layout plan proposed in this paper can play a good role in guiding offshore step-down substations in oilfield group project and has high reference value.

[Introduction] Reasonable selection of key equipments of flexible DC distribution network will help to optimize the layout of the converter station, and it also plays an important role on improving the reliability of the converter station and reducing the investment cost of the project. [Method] By introducing the key equipments of flexible DC distribution network of Tangjiawang typical project in Zhuhai, the advantages and disadvantages of different types of key equipments were analysed and compared, and the the selection suggestions of key electrical equipment were given. [Result] By focusing on the analysis of the type selection scheme, this paper expound the principle of equipment selection for flexible DC converter station and provides the research basis for the future project of flexible DC distribution network. [Conclusion] The relevant research results of this paper can provide important reference for the simulation modeling and the engineering design of flexible DC distribution Network projects in the future.

[Introduction] Basically, the centralized wind power projects in South China or on land have been developed, and the distributed wind power projects based on making full use of the idle land around villages and towns or factory areas have sprung up. It is expected that the distributed wind power generation which utilizes low-speed wind will bring new incremental space for the domestic wind power market. Whether the location of distributed wind turbine is right or not will directly affect the economic benefit of the power station. Due to the fact that there is no support of wind resource data actually measured on the idle land around villages and towns or factory areas, it is facing a great challenge to develop distributed wind farms or select the site and type of the wind turbine. [Method] This paper put forward the idea of finding the load first, then selecting the site of wind power plant, and to analyze and select the best wind turbine location depending on the meteorological data of wind resources. [Result] The research shows that： taking the design of a distributed wind farm in South China as an example, by adopting the idea of distributed-wind-power plant site selection and wind turbine type selection proposed in this paper, making full use of the idle land around the factory and mine, the optimal design suggestion of selecting to use three sets of 3X anti typhoon type wind turbines with 100-meter-high hub is reached. [Conclusion] The proposed idea of distributed wind power plant location and wind turbine type selection is correct and effective, which can provide guidance for practical operation.

[Introduction] In domestic thermal power plants, traditional line transmission technology is still used in the fuel management system, which lacks flexibility, reliability and mobility in terms of data integration processing or interconnection with the cloud platform. Data communication is an important development trend of intelligent power plant management, and the higher transmission rate is the goal of building a big data cloud computing platform for smart power plants in the future. This paper provides a reference for studying the application of higher-speed wireless data transmission in power industry, building and applying the latest wireless transmission technology in power plant data transmission network and integrating it with smart power plant big data platform. [Method] Firstly, this paper introduced the current status and composition of fuel management platform in power plant, and described the 5G and WiFi6 technology, which was integrated into the existing network architecture of power plant management platform, so as to realize efficient application and optimization research. [Result] By analyzing the problems existing in most of the fuel management platforms in power plants, the high-speed network can effectively improve the operation safety and stability of power plants and bring greater economic benefits. [Conclusion] The construction of a wireless high-speed and complete data transmission system is more conducive to the effective and safe construction of intelligent fuel management platform, which should be designed and planned in the early stage of the project and applied to thermal power generation industries.

[Introduction] Under the new environment of power market, the power system planning contains more variables, constraints, planning objectives and complexity. The uncertainty variables include load, power supply, power flow, equipment retirement, policy, social economy, bussiness mode, investment profit, etc. It is necessary to establish appropriate plannnig model based on the complexity mentioned above. The research methods of the whole power planning and means need to be further optimized. [Method] Firstly, this paper reviewed the status quo of the more mature power markets in Australia, PJM in the United States, Europe and other foreign countries, and analysed their power system planning models and methods. [Result] Combined with the current situation of Guangdong power market development, this paper optimized the planning method of Guangdong power system under the power market environment. Not only did it give suggestions for optimizing and adjusting the institutional mechanism of power planning work, but also complemented and improved the five aspects of planning input, project classification, scenario study, grid economic efficiency assessment and uncertainty analysis according to the traditional Guangdong power system planning method. [Conclusion] Under the new environment of Guangdong spot market of energy, by establishing a reasonable power system planning and evaluation system, it can be beneficial to rationalize allocation of power sources, achieve coordinated planning between network sources, and better adapt to the future development of the power market.

[Introduction] This paper summarized the formation and development of the China technology market since China's reform and opening up, as well as the great practices and outstanding theoretical contributions by the Communist Party of China (CPC) and the Chinese government in the process of cultivating and constructing the technology market by focusing on studying and exploring what the technology market is and how to build it, based on the opportunity of unprecedented changes in co-existence of chances and challenges, and from the perspective of further strengthening the cultivation and construction of the China technology market in the new period. [Method] From the perspective of summing up experience and learning lessons, with the viewpoint of dialectical materialism, based on the problems regarding further strengthening the cultivation and construction of the China technology market in the new period and in terms of government management under the market mechanism, this paper analyzed the relationship between the cultivation and construction of the technology market, the master-slave relationship between the technology market and the talent and capital markets, the relationship between cultivating and establishing the scientific and technological service chain and aligning it with the scientific and technological innovation chain and the industrial chain, and the great significance of building a powerful scientific and technological service market and promoting the healthy development and continued prosperity of the China technology market in the new period. [Result] This paper holds that the China technology market as a prominent social phenomenon in a country where the market economy has not been completely formed, is the result of the great choice prudently made by the central government after boldly breaking free from the shackles of the outdated planned economic system — implementing commodity economy and pursuing market economy until it establishes a national market economic system. It fully reflects the persistence, dashing and innovative spirit and bold practice of the Chinese people and scientific and technological staff in implementing the central government's reform and opening-up policy, and the country's unprecedented great practice of "vigorously exploring the technology market". It also presents their huge achievements in boosting national scientific and technological progress and national economic development. From theory to practice, the central government has successfully made a historical leap from the planned economic system to the initially established market economic system. This shift marks the Chinese people's theoretical contribution to scientific socialism in the world, which has important theoretical value and contemporary significance. This paper raises a series of viewpoints with a certain research depth and exploration value. Especially with regard to the logical relationship between the emergence of the Chinese technology market and the proposal of the policy that requires the country to carry out reform and opening up, and the establishment of a socialist market economic system, this paper analyzed the master-slave positioning and interactive relationship between the technology market and other socialist production factor markets in China. In addition, it put forward its unique views and suggestions, especially on the major contributions made by the technology market to promoting the national scientific and technological progress and the rapid development of the national economy. [Conclusion] This paper sorts out and analyzes the activities in the Chinese technology market and various problems in practice, clearly reveals the essence and connotation of the technology market, and clarifies its functions and roles. In order to further develop the technology market in the new period and continue to play its roles in promoting the country's economic and social development and building a powerful country in science and technology, service and manufacturing, this paper calls on the Chinese government to effectively strengthen management and services regarding the construction and cultivation of the market, and take quick actions to make the two major tasks to be the important responsibilities and central themes for building an innovative country in the process of building and cultivating the Chinese technology market in the new period under the market economy system. These tasks and responsibilities refer to changing the current work system of the technology market where operation and management are not distinguished, as well as creating and developing a sound development environment to build a powerful scientific and technological service market.

[Introduction] Load, as the part that ultimately consumes active power, has a very important impact on the stability of the system. Therefore, the influence of different load models on out-of-step oscillation characteristics of power system is studied in this paper. [Method] This paper took a large grid’s regional discontinuity as the research target to comprehensively analyze the effects of different load models on the oscillation center and action of out of step splitting device using BPA program developed by China Electric Power Research Institute. [Result] The simulation results show when using the ZIP static load model, the line Ucos curve demonstrates the best periodic integrity, as the proportion of induction motor type load increases, the Ucos curve’s periodic integrity becomes worse, it even leads to a subversive change in the conclusion whether the out of step splitting device can react. In addition, different load models also cause the oscillation center migration. [Conclusion] Therefore, the credibility of simulation results can only be guaranteed by using the most realistic load model.