Advanced Materials Research Vols. 805-806

Abstract: The development of CdTe/CdS solar cells on flexible substrates is reviewed in this article. Photovoltaic structures on lightweight and flexible substrates have several advantages over the heavy glass based structures in both terrestrial and space applications. The cells mounted on flexible foil are not fragile, the requirements of the supporting structures are minimum and they can be wrapped onto any suitably oriented or curved structures. The specific power of the solar cells is an important factor in space applications and hence development of photovoltaic devices on light weight substrates is interesting. CdTe is one of the leading candidates for photovoltaic applications due to its optimum band gap for the efficient photo-conversion and robustness for industrial production with a variety of film preparation methods. Flexible solar cells with conversion efficiencies exceeding 11% have been developed on polyimide foils. The development of CdTe devices on metallic substrates is impeded due to the lack of a proper ohmic contact between CdTe and the substrate. The polymer substrate has the advantage that the devices can be prepared in both superstrate and substrate configurations.

Abstract: Five reasons for vertical integration investment are reduction in transaction costs, access to economies of scope, and reduction in risks and damage, upgrading of competitive advantage and strategic profits. Some upstream photovoltaic manufacturing enterprises through analyzing their decision-making behavior for vertical integration of PV industry draw a conclusion that if they invest in their lower counterparts, their vertical integration behavior will come to two effects: competition effects and cooperation effect.

Abstract: Solar thermal power system can be classified to three typical kinds, parabolic trough, tower and dish system. Trough and tower systems have been commercial operated in last few years. Solar dish power plant is also in demonstrational phase. But how to choose a fit technology road is also a different challenge. In the paper, three solar thermal power plants are analyzed, located in same location in Gansu province. Three power plants electricity loads and total investments in same capacity and collector area are calculated to analyze the economic characters by Levelised Electricity Cost (LEC) method. Finally, three power plants LEC distributions are also analyzed in the conditions of different loan interests and life span. The results indicate that the minimum LEC is tower in current market conditions. The research results can be used to support technology choice, and design optimization in specific climate condition.

Abstract: Solar Linear Fresnel thermal power plant is typical linear focus solar thermal system. It has the advantage of simple structure, lower investment cost and so on. At present, Solar Linear Fresnel is developing and popularizing all over the word. Some of them are already in commercial operation. According to the typical climate data, the thermal character and generating capacity of Linear Fresnel systems are analyzed, including thermal receiving efficiency, power generating efficiency and thermal losses regularity. The research results can be used to support Solar Linear Fresnel system operation and design optimization.

Abstract: Automatic identification of defects on solar cell modules is the key of improving components efficiency of power generation and achieving the maximum utilization of energy[1]. This paper took the debris defects as an example. Considered the fact that scale factor would have an impact on moment invariants in discrete state, this paper adopted an improved moment invariant for the image feature extraction of debris defects. The scale factor of the new moment invariants is eliminated by transformation. Therefore they have the properties of translation, rotation and scaling simultaneously. Meanwhile, SVM (Support Vector Machine) classifier was used to identify the debris defects. The experimental results show that, compared with the traditional moment invariants, the identification rate of using the improved moment invariants for feature extraction is 96%.

Abstract: The PV system generation changes with insolation rapidly and randomly ,and the change of power-flow increase the flicker severity in grid. The IEC standards 61400-21 provides recommended test method for wind turbines. In this paper, a model including virtual grid and flickermeter is developed. The testing and simulation procedure for PV inverter is proposed and finally, the test result is demonstrated.

Abstract: In this paper, a new method is proposed to test the conducted and radiated electromagnetic interference (EMI) noise of photovoltaic invert based on analysis the internal structure and measuring principle of artificial mains network, meanwhile, the power line radiated EMI noise of photovoltaic can also be estimated by CM noise current using current probe and CM noise extraction network. The experiment result show that the conducted EMI noise and radiated EMI noise of photovoltaic inverter can be test more reasonable by this method.

Abstract: Nanostructure strategies are frequently used to enhance the light absorption in solar cells. For improving the efficiency of absorption in solar cells, an industrial-feasible processing technique, i.e. low-pressure chemical vapor deposition was used to form a substrate with large-area silicon nanoparticles (Si-NPs). It was shown that the density and size of Si-NPs can be modulated by controlling the flow of pure SiH4, the deposition temperature and the deposition time. The substrate with large-area Si-NPs can be applied in photovoltaic devices since they can increase the effective absorption path of the incident sunlight.

Abstract: This paper provides the electromagnetic environment test results of the new energy laboratory, and analyzes the results by comparing with the related traditional electromagnetic energy environmental standards from domestic and overseas. This paper lays the foundation of setting up the new standard for the electromagnetic environment of photovoltaic system, and provides important data for reference.