Advanced Materials Research Vol. 772

Abstract: In the paper is presented a parametric study on possibilities of designing and realizing a prestressed reinforced concrete tower for a wind turbine, WEG 400, as an alternative solution replacing a steel structure. WEG 400 is a generation of a double-blade wind turbine with the rotor diameter of 36.7 m. Key design criteria include extreme static/dynamic loads, cyclical loading and natural frequency. The supporting structure of the tower needs to be easy to dispose from prefabricated prestressed concrete elements.

Abstract: In this paper, the factors are analyzed,which affect the accommodation capacity of large scale PV power generation access to the grid . The analysis method mainly consider the peak load adjustment ability of the whole power system. Then a real case based on provincial grid is calculated and analyzed. The results show that: As an important technical style ,the generation and acommodation of the large scale photovoltaic power generation are influenced by the light resource, load level, adjustment ability, transmission channel. The planning of large-scale photovoltaic power plants must keep pace with the conventional power and grid planning.

Abstract: Photon Enhanced Thermionic Emission (PETE) is a novel concept in solar energy conversion, which can efficiently harvest solar energy at elevated temperatures. However, the temperature dependence of material parameters has not been clearly stated so far. In this study, a model for carrier transport is presented based on one dimension diffusion equation. Material data of GaAs are used to testify the temperature impact on material parameters. We find that for higher doped p-type GaAs which is suitable for PETE cathode material, its electron diffusion length shows weak temperature dependence. Carrier transport efficiency can be boosted by optimizing the geometry of the cathode and the optical parameters of the material. Finally, we propose a design of reflective mode cathode with reflective back surface and nanostructure emissive surface for PETE application.

Abstract: In order to realize electric power high voltage, large capacity, long distance transmission and regional power grid interconnection, dc transmission system is an important technical means, and it plays an important role for cross-regional given of new large-scale energy power generation. Based on large scale photovoltaic (PV) power generation access to the northwest power grid as the object, this article set up PV power station model, analysis the influence of large-scale PV power access to HVDC system under different PV station operating mode and the grid disturbance situation. At last this paper puts forward suggestions and measures to guarantee stable operation of large scale PV power generation access to the system.

Abstract: In the paper, new energy industrial standardization status quo of NingXia Province is analyzed. The frame diagram of new energy standard system of NingXia Province is established based on the standard retrieval database. According to the new energy industrial standard system frame diagram, reasons of restrict the new energy industry development of NingXia Province are analyzed and some suggestions are proposed. Finally, some proposals about new energy industry standard system construction are offered.

Abstract: This paper presents the engineering analytical models of photovoltaic (PV) water pumping system from electronics theory, and some mathematical models of system components have been established. Studies have shown that the minimum unit water cost may not be reached only with the control strategy of maximum output power of the system. Therefore, system optimization is very necessary to reducing the capacity for every unit of pumped water, which is based on the design optimization theory and has shown its economics.

Abstract: We propose a method of piecewise linear approximation with temperature compensated to model the characteristics of the maximum power points locus of photovoltaic panel under different irradiance levels and temperatures. This method can fast tracking photovoltaic panel maximum power point, and can also overcome the problem of the temperature drift. The simulation and experiment results indicate that, the maximum power point tracking efficiency of the proposed method is up to 90% ~ 99.9% under diffident irradiance.

Abstract: This paper addresses applications of Central Angle, a concept being widely spread in the context of Phasor Measurement Units (PMU). Making reference to Cutset Area theory, the Central Angle is calculated. A digital model to give alarms for operators to prevent feasible blackout conditions is proposed and tested in a Colombian electrical network. The performance and robustness of the model is verified with multiple contingencies.

Abstract: This paper focuses on how to develop the wind power industry professional competence course, the use of the professional competence results of the aforementioned studies, construction of the wind power industry professional competence course module. The importance of the analysis found that students give the highest rating to Chapter 5, work attitude and ethics in the workplace, followed by Chapter 1 green beliefs and regulations, followed by Chapter 4, the future trends of wind power, Chapter 2 Principles of wind power, and Chapter 3 the wind power generation equipment and the establishment. The values of average important of 5 chapters are between 3.66 and 4.07, Less than 4.00, and the average percentage of correct answers (knowledge) of 5 chapters between 28% and 55%, Less than 60%. The IPA analysis found that all on the B quadrant. It is mean that the textbook of wind power is suitable for use and whether experts or students who believe that wind power education is important. Although wind power capacity is insufficient, the students believe that the importance of wind power technology is certainly, that is part of our textbooks to add.

Abstract: The combination of solar thermal and PV technologies leads to form a single module called PVT system. This system is able to produce heat and electricity simultaneously. In this paper, a new configuration and design of PV/T system are proposed, and a theoretical study of this system is evaluated. The PV/T consists of certain layers which are the glass, air gap, PV panel, absorber plate and insulating material layer. The monocrystalline PV and spiral flow absorber plate are used in this study. The results of the system performance under typical sunny climatic Malaysian condition are presented. The maximum thermal and electrical efficiencies obtained are 64.4 % and 12.13%, respectively. The effect of mass flow rate on the outlet water temperature is also evaluated. It is shown that the optimum mass flow rate for the designed system is between 0.005 and 0.075 kg/s.