Advanced Materials Research Vols. 953-954

Abstract: The studied results found it can not only reduce the thickness of the solar cell but also improve the light absorbed efficiency by using grating as light trapping structure. In this paper, a dual grating periodic structure is designed to improve light absorption efficiency over the spectrum range 330-1400 nm. Then the relationship between groove-depth of dual grating and absorption efficiency is investigated by using finite difference time domain method (FDTD) combining with periodic boundary conditions (PBC).

Abstract: A continuous solar desalination system with humidification-dehumidification cycle was devised. Solar energy was chosen as the main heat source, the electric heater the auxiliary heat source, and the hot water reservoir the energy storage unit. To ensure the 24-hour continuous production of fresh water, four specific operation modes were designed and analyzed for the conditions of average, excess, insufficient and no illumination intensity respectively, based on which the methods for the judgment and calculation of process parameters were derived.

Abstract: In order to increase the output power of the photovoltaic system, the maximum power point tracking is needed. As the starting point of research in the output nonlinear characteristics, analysis of the advantages and disadvantages of the conventional algorithm and have the poor dynamic and steady-state performance of the maximum power point tracking(MPPT), the improvement method of golden section(IGSS) is applied to the photovoltaic power generation system. The results indicate that the method can quickly track the maximum power point of photovoltaic cells.

Abstract: This article conducts the research on the relationship between the solar radiation and the adsorption bed temperature, the adsorption bed pressure and the system performance, and obtains that the solar radiation indirectly influences the system refrigeration performance through influencing the adsorption bed temperature and adsorption bed pressure. And in a certain range, the bigger solar radiation is, the higher adsorption bed temperature is, the system refrigeration efficiency is higher, the maximum refrigeration efficiency is 0.122.

Abstract: In recent years, with the gradual depletion of traditional energy, as renewable energy representatives, new energy has developed rapidly. We know that distributed photovoltaic power generation with clean, pollution-free, easy installation, and therefore has been rapid development. However, the large number of distributed photovoltaic power generation connected to the distribution network would have a negative impact on the grid with a safe and reliable operation because of its randomness and volatility intrinsic properties. In this paper, in terms of power flow, voltage distribution, load characteristics, power quality, system protection and reliability departure, through MATLAB simulation analysis, the distribution network transformation strategies of primary and secondary devices has been proposed. It laid an important foundation for renewable energy development and the Third Industrial Revolution.

Abstract: This paper presents the design of a solar/gas driving double effect LiBr-H₂O absorption system. In order to use solar energy more efficiently, a new kind of solar/gas driving double effect LiBr-H2O absorption system is designed. In this system, the high-pressure generator is driven by conventional energy, natural gas, and solar energy together with water vapor generated in the high-pressure generator, which supplies energy to the low-pressure generator for a double effect absorption system. Simulation results illustrate that this kind of system is feasible and economical. Economic evaluation of several systems is also given in this paper in order to get a clear knowledge of the energy consumption of the system.

Abstract: A CPC for LFR system was designed and its mathematical model was established. Maximum acceptance angle and truncation ratio was optimized to 45° and 0.75, which two elements mainly affect the optical performance of CPC. Moreover, the non-uniform of incident angle can considerably improve the CPC concentration ratio. Results show that the CPC with 475.49mm opening width could achieve a high concentrate ratio reach up to 80.15%. This conclusion was further verified by an experimental measurement results.

Abstract: The grid-connected photovoltaic (PV) has series of effects on the distribution network, the effects become increasing with the PV capacity continues to increase, so, the research on the maximum penetration level of Grid-connected PV the power system can accommodate is very important. In this paper, the influences of connecting PV to the distribution network is firstly analyzed, An calculation model is proposed for computing the maximum penetration level of Grid-connected PV to insure every node voltage not beyond limits, taking into account on-load-changing of the transformer and the influences of PV power is completely out of operation. The experimental analysis shows that the proposed calculation model for computing the maximum capacity is feasible and effective. KETWORDS: Photovoltaic (PV);distribution network ;Maximum penetration level; on-load voltage changing

Abstract: Solar energy is a kind of clean and green energy, its use can reduce the dual pressure of resources and environmental pollution. Firstly, this paper introduces groove, tower and dish type solar thermal power generation system. Then it introduces the components of dish-stirling system and the principle and features of stirling engine. The system has simple structure, reliable operation, high efficiency, low noise, low cost of power generation and good commercial prospects. But for some key parts of system, there are many problems that need to be solved. The main research of dish-stirling system is to optimize the key parts of system and reduce the system costs.

Abstract: In the paper, the discharge process of double frequency capacitive coupled Plasma in argon gas has been investigated by one dimensional PIC/MCC method. The result shows that the rf voltage in fluence the density and Potential deeply. Furthermore, the effect of various driven voltage on ion energy distribution (IED) and ion angle distribution (IAD) at the electrode is studied. It is found that when the driven voltage grows, the Peak of energy increases. At the same time, the high energy ions distribution increase clearly too. The content of bombardment to the intrinsic thin layer of a-Si:H is analyzed in the condition of various driven voltage. The critical driven voltage is calculated, which can keep the plasma discharge process and not erode the intrinsic thin layer in the HIT solar cell.