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RSS2015 Vol. 2, No. 2
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2015, 2(2): 1-8.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.001
Abstract:
Based on indicating historical law of economy-energy-environment, it is illustrated that realizing "China's Dream" calls for implementing "Complement & Partially Stride Over" strategy; grasp the historical opportunity of urbanization/industrialization, intelligent energy network establishing, based on developing abundant natural gas resources and guarantee the reasonable price, emphasize to develop thousands of regional natural gas power, CHP and CCHP, which operating as 16 h/d model, in order to cooperate with grid for electricity network balancing. It is the integrated creation of energy utilization model. Up to 2020/2030, its volume would reach 200 GW/450 GW, 15% of the nation's total power generated, resulting in the energy efficiency increase from 37% up to 50%, eliminate most fog & haze due to terminal coal burning and reduce emission. Finally, work out the low-carbon energy strategy, substitute administrational approving with legislating, gas-turbine manufacturing and commercial model innovation and so on are advanced.
2015, 2(2): 9-14.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.002
Abstract:
Based on the topology analysis of energy grid and operational research method, presents the logical scheme of coordinated optimization for the system, incorporated energy trade and flow plan, energy generation and storage plan, operation plan of energy using equipment, etc., the energy grid is divided into two layer architecture in which has gas, electric power, heat(cold). The built math models and study case of regional distributed energy grid proves the academic validity of proposed scheme.
2015, 2(2): 15-19.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.003
Abstract:
According to the natural environment drought, water shortage, high sand and the restrict use of natural gas in Western China, this paper proposes a technical scheme of the compressed air energy storage. The thermodynamics process of energy storage and power generation have also been analyzed, while the compression process index, maximum gas pressure and turbine inlet temperature on the influence of system energy conversion efficiency have been paid much more attention. The research result shows that: 1, with the increasing of the polytropic index, the system electricity ratio nearly keeps constant, while the energy efficiency increases and the heat ratio greatly decreased. 2, the system electricity ratio and the heat ratio increase with the increasing of the pressure in high pressure vessel, the energy efficiency decreases with the increasing of the pressure in high pressure vessel. 3, the system electricity and the heat ratio decrease along with the rise of inlet temperature in high pressure gas turbine, and the energy efficiency increases with the increasing of inlet temperature in high pressure gas turbine. The study of this paper has a certain reference value in the large-scale promotion application in China.
2015, 2(2): 20-27.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.004
Abstract:
In the case of that a micro-grid with high penetration of renewable resources is accessed into a power distribution network, the micro-grid's treatment mode and transient performance under the short-circuit fault condition will affect the power distribution network's operation characteristics dramatically. This paper analyzes the micro-grid's treatment modes corresponding to different fault locations, and proposes a technical idea considering the coordinated control of the fault current limiter and energy storage allocated inside the micro-grid. It is expected to actively strengthen the micro-grid's fault ride-through(FRT) capability as far as possible. And for some specific faults, the micro-grid should disconnect from the main network, and the coordinated control strategy can make the micro-grid implement a smooth transition between its grid-connected and islanded modes. Besides, directing at the some key issues related to the micro-grid's fault ride-through capability, the survey of research situation at home and abroad is carried out. At last, a typical micro-grid system is selected, and the simulation analysis is done to verify the effectiveness of the coordinated control.
2015, 2(2): 28-34.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.005
Abstract:
Micro-grid is the effective way of accommodating distributed generation. Energy storage (ES) system in micro-grid can be contributed to the improvement of power quality, power balance control, operation stability enhancement and optimal energy management. A hybrid energy storage system (HESS) combines the high power density ES unit and the high energy density ES unit efficiently, and has the advantage of both type ES unit, which can be controlled effectively to improve the operation characteristic of micro-grid. In this paper, the application of the HESS in micro-grid was studied from aspects of application mode, control strategies and optimal allocation. Firstly, according to the different connection mode between the ES unit and the system bus, the application of the centralized HESS and the distributed HESS are analyzed. Secondly, based on the control method of ES to improve the operation of micro-grid, the coordination control of ES unit in HESS is summarized. Finally, the issue of optimal allocation of HESS in micro-grid is analyzed. Integrating with the coordination control of HESS, the suggestion for optimal allocation of HESS is proposed.
2015, 2(2): 41-45.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.007
Abstract:
Integrated energy system is a complex system, and index data of internal system are also complicated, which can make index information incomplete. So when evaluating the comprehensive benefits, due to the incomplete index information, the final evaluation results will appear errors, which bring huge economic losses. Based on the characteristics of integrated energy systems, we used the multiple-attribute decision-making method based on the normal distribution interval number to solve the problem of benefit evaluation of incomplete information, and sorted the plans by expectation variance criterion. Finally, we verify the applicability and effectiveness of the method in the evaluation of integrated energy system by calculating a case.
2015, 2(2): 46-51.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.008
Abstract:
As to maximize the benefit of the distribution network with Distributed Generation, the reconfiguration of distribution network with distributed generation is referred to. This paper puts forward an algorithm combining the adjacency matrix and the particle swarm optimization according to the common distribution network pro-type. According to the characteristic of the distribution network with distributed generation, it builds the mathematic model of the network, which aims at a minimum load loss. Program this algorithm on Matlab and apply this algorithm to the case, then the results show that it has a characteristic of not depending on initial structure of the network, working rapidly and efficiently by avoiding the complex calculation. It proves a better practical use.
2015, 2(2): 52-56.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.009
Abstract:
Internet data center(IDC) has a high demand for electricity and cooling, as well as high reliability for the energy supply. Via graded use of energy, the distributed energy system(DES) has the high efficiency and is environment-friendly and flexible operational, accordingly it is adequate for energy supply of IDC. A natural gas DES scheme is designed for a data center in Guangzhou. The results shows that the scheme is feasible since it can increase the reliability of energy supply, reduce operating cost and decrease air pollution.
2015, 2(2): 57-61.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.010
Abstract:
Technical and policy environment are summarized in this paper. Application of distributed power in the actual user is analyzed. Operation mode of DG is calculated in this paper. The result shows that DG can be used in practical application conditions in many areas such as city special user, industry factory, and so on. With development of economic and policy, DG will be applied more widely in many fields. They will bring the profound influence to the existing power supply mode.
2015, 2(2): 62-65.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.011
Abstract:
The reliability of distribution system including distributed generation (DG) need to be analyzed while the DG technology has been used widely now. Traditional reliability assessment theory can hardly to be applied, because basic historical DG reliability data has not been accumulated. The distribution Systems reliability assessment including distributed generation based on credibility theory is proposed to solve this problem. Three new reliability index are proposed: Random-Fuzzy Expected Energy Not Supplied(RFEENS), Random-Fuzzy Customer Average Interruption Duration Index(RFCAIDI), and Random-Fuzzy Customer Average Interruption Frequency Index(RFCAIFI). Assessment procedure for RFEENS and RFCAIDI is based on random fuzzy expected value, while the procedure for RFCAIFI is based on average chance Measure. The test results on IEEE system demonstrate that the proposed method is flexible enough to accommodate system's security objectives.
2015, 2(2): 66-69.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.012
Abstract:
Based on the gas engine distributed energy supply systems, the heat sources, temperature and usability of the waste heat were analyzed. The back pressure and temperature of gas engine discharge and the pressure drop which should be noticed on the heat recovery system design were studied. The work principle and technology of the main kinds of heat recovery equitments were researched. The results provide reference to the heat recovery system design of gas engine distributed energy supply system.
2015, 2(2): 70-75.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.013
Abstract:
The current biomass direct combustion power generation is the material of a mainstream technology, boiler design, biomass power plant technology in the core and select what kind of stoves, not only affects the biomass power plant of the investment, economic transition, and also affects the biomass power plant life. The thesis proposed biomass fuel has been in power plants several oven-to do more research, biomass has been fuel power plants of the furnace-select recommendations for biomass power plant design reference.
2015, 2(2): 76-79.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.014
Abstract:
A new solar-powered combined heating and cooling system is designed based on the concept of energy saving and environmental protection, this system has high efficiency which use semiconductor chilling plate powered by solar energy to produce refrigenation effect, and the waste heat is used to supply domestic hot water. Theoretical calculation and numerical simulation are finished based on energy balance and heat transfer theory, the results shows that this system can realize the function of the refrigeration and hot water supply, which COP is 0.7 and energy utilization efficiency is 73.5%.
2015, 2(2): 80-85.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.015
Abstract:
With the development of power grid technology, distributed energy storage becomes an important technical support which promotes smart grid construction and enhances the optimal allocation of grid. In this paper, based on the requirements of new energy access, improving power quality, improving the reliability of supplying electric and power distribution station in Guangdong power grid, presents that distributed energy storage is an important technical means to meet the above requirements, introduces the categories, features and functions of the energy storage device, combined with examples, the specific applications of distributed energy storage device in various fields has been studied, finally presents the guided suggestions to the development of distributed energy storage device in Guangdong Province.
2015, 2(2): 86-90.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.016
Abstract:
As a clean non-polluting and renewable energy, small hydropower has great ecological and social benefits and its importance is increasing. Usually, Small hydropower is dispersed on mountainous regions. Most of small hydropower is run-of-river hydropower plant. The line voltage often leaps over the floor or ceiling following the varied output of small hydropower which is T-connected to the 10kV feeder disorderly. It seriously affects the distribution network's normal operation. In this paper, a control method based on fexible network is propsed to change the direction of the power flow and control the line voltage by adjusting the small hydropower's connecting position. Based on a regin of Guangdong with rich small hydropower, a simulation case is established to verify the correctness and applicability of the method which is proposed.
2015, 2(2): 91-95.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.017
Abstract:
Short circuit current cause great threat to the safe and stable operation of the power system. Saturated core type Superconducting Fault Current Limiter (SFCL) has a lot of advantages such as small steady impedance, low loss, short recovery time, and good current limiting effect. It is one of the ideal equipment for limiting short circuit current in power system. The working principle of saturated core superconducting fault current limiter is introduced. And its development situation is expounded. Based on these, this paper analyzed the key problems of its application technologies.
2015, 2(2): 96-101.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.018
Abstract:
The main building of nuclear power station is a special kind of industrial structure, with irregular in mass and stiffness. The analysis and design should be carried on very carefully. If functional disruption or damage to the equipment during an earthquake, huge damage will be generated. the perform-based seismic design method is used to the main plant structure, the seismic bearing capacity and deformability capacity are both scrutinized, to ensure the seismic capacity of the main plant to achieve predetermined seismic aims. Design can be based on the current code for seismic design of buildings, and the evaluation of deformability capacity can be based on the element level. On this basis, five seismic waves recorded are used on the main plant structure.Results show that through reasonable design the main power building can have larger redundancy to avoid collapse under earthquake and sudden loss of bearing capacity of its key component, and can ensure the safety of the nuclear island.
2015, 2(2): 102-106.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.019
Abstract:
Turbine Generator is one of the most important electrical equipment of the main nuclear power plant, the stability of its operation directly affect the stability of the entire power system. Codes in different countries proposed different technical measures on the turbine generator foundation design, these measures have started from lower base line vibration displacement or vibration velocity. Selection of the proper foundation, smaller economies can achieve in vibration control. This paper analyzes the differences between Europe and America of its design concept, the isolation performance of the spring vibration-isolated foundation are discussed in detail, its show that the spring vibration-isolated foundation can be more suitable for the European nuclear power plant steam turbines. The high quality of spring vibration-isolated foundation in low frequency, aseismicity and adjustability is great to assure the safe operation of China first Nuclear 1 000 MW Class Half Speed Turbine Generator.
2015, 2(2): 107-110.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.020
Abstract:
A comparison of reliability design was studied between <Developments of a probability based load criterion for American national standard A58: building code requirements for minimum design loads in buildings and other structures> and Chinese code for reliability design (GB 50068—2001 and GB 50153—2008). It is analyzed similarities and differences of five aspects, such as the definition of reliability, the principle for reliability set, the influence factor, the measurement for reliability index and the method to ensure the reliability level. The conclusions can be referenced for probabilistic safety analysis (PSA) and structure design specification revising in the future.
2015, 2(2): 111-114.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.021
Abstract:
This paper proposes a new calculation method of transmission network reliability index, to estimate reliability of electrical transmission network. First of all, the reliability index of series-and-parallel system is calculated based on the effectiveness index of the maintainable network elements, and then the reliability index of the complex transmission network is calculated, which directly reflects the average annual fault time of centralized business. This approach is consistent with the transmission network, and the calculation is simple. Using this method, it is intuitive and quantifiable to verify the effectiveness of network optimization on improving network reliability.
2015, 2(2): 115-118.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.022
Abstract:
PTN network combines the advantages of SDH and traditional Ethernet. It can satisfy the smart grid for time synchronization, multicast, QOS and so on. This paper analyzes the time delay requirements of wide-area protection, the requirements of communication channel reconvery time delay with the same path and PTN protection technology. And we study the network protection technologies suit to the PTN networks carrying the wide-area protection. Finally, the time delay of Wrapping protection and 1∶1 LSP protection are verified by simulation testing. The simulation results are shown that Wrapping protection and 1∶1 LSP protection can meet the requirements of the wide-area relay protection in the PTN network.
2015, 2(2): 119-123.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.023
Abstract:
Due to its ease to use, the Green-Ampt model is potentially very useful for infiltration analysis for predicting of slope failure. In this study, the governing equation for infiltration analysis on sloping surfaces in layered soils is derived. The depth of wetting front predicted from the modified Green-Ampt model is close to that predicted based on Richards' function. Based on the limit equilibrium method, the safety factor calculation.in layered slope is proposed. Research shows that along with the increase of the rainfall, the wetting front position down gradually and the safety factor decreases.When the lower soil's strength is higher, the most dangerous sliding surface will be at the bottom of the first layer of soil, the safety factor will not change with time. However, when the infiltration depth is large enough, the most dangerous sliding surface will locate at the wetting front again, the safety factor will change.And, the safety factor is influenced by the rainfall intensity and slope angle, thus the slope will be more instability under the condition of high rainfall strength and steep slopes. In this paper, the modified method is simple, can be more easily applied to the engineering practice, and has value to further study.
2015, 2(2): 124-128.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.024
Abstract:
Availability test for the power plant is a comprehensive test of total quality, which is a comprehensive test for the rationality and redundancy of plant scheme, quality, installation, commissioning and operation. It is also an key index to judge the successfulness of an oversea EPC power plant project. International common practice is used to illustrate the meaning of availability and the common penalty about the unit availability. Quantitative analysis method of calculation of the risk of availability is given and also the measurement to figure out the penalty of availability. The conclusion of this paper will give an guidance for more and more chinese enterprises which go oversea.
2015, 2(2): 129-132.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.025
Abstract:
The solar photovoltaic power will depend on the development of its economy is reasonable, this paper mainly studied on the cost analysis model of the solar photovoltaic generation and the influencing factors, a quantitative analysis of the loss reduction, the benefits of the user saves the electricity and the generation benefit analysis. the results of the simulation calculation of IEEE 36 nodes distribution system show that the grid side and user side can produce remarkable economic benefits by reasonable planning of the solar photovoltaic generation.
2015, 2(2): 133-139.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.026
Abstract:
In Tibet and Sichuan high-altitude area, power engineering construction scale expanding in recent years. Accurately grasp the cost level of the substation engineering in Sichuan Tibet high altitude area, reasonable control of investment and ensure investment benefits and the smooth implementation of the project, which is the technical difficulty worthy of further study and thinking. Just in the same area between Sichuan and Tibet, in the same altitude regions, on the basis of the Sichuan Tibet networking power engineering cost related statistical data, focus on analysis of the influence of different quota and cost standards′ changes on investment of Sichuan Tibet high altitude engineering, planning for the future construction of special high-voltage power grid to further optimize the economic rationality, mainly for the design experience.
2015, 2(2): 140-145.
doi: 10.16516/j.gedi.issn2095-8676.2015.02.027
Abstract:
To ensure the condition-based maintenance and hidden trouble detection of power equipments carried out smoothly, the application of live detection on the operation and maintenance of power grid equipments has been as the focus of various works. In this paper, the principle and the suitable objects that widely used in the operation and maintenance of power grid electrical equipments, such as infrared detection, ultraviolet imagery, ultrasonic method, ultrahigh frequency (UHF), transient earth voltage (TEV), harmonic electric field method and chemical composition analysis method are summarized, some conclusions would provide reference for the following engineers that engage in the power grid live detection work.
