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The subject of this master’s thesis is to introduce concentrator photovoltaic systems. Main subject of presented work are photovoltaic cells and their features and characteristics. The work deals with physical fundamentals of solar cells, type of cells and their specifics and discusses possible treatment for achieving better characteristics of concentrator systems. In the practical part is realized measurement and analysis of electrical characteristics of 9 different monocrystalline silicon cells. From those is the most efficient cell chosen for further use as reference cell.

Diagnostic of photovoltaic cells defects is one of the key step in production. This dissertation thesis deals about diagnosis of photovoltaic cells by radiative recombination of electron - hole pairs. This radiative recombination is known as luminescence. Diagnostic methods using this local light emission in infrared region have innovative potential. The method of electroluminescence is one of the most widely used luminescence methods whose modifications are applied across the industry, especially in semiconductors. The main area of this thesis research is focused on non-destructive analysis of radiated infrared radiation of monocrystalline and polycrystalline solar cells in various modifications of standard electroluminescence method. In this research there are used two types of CCD cameras are used as luminescent radiation detectors. Method of photon emission microscopy is used for magnification element. Local light emission inspection by microscopy should have benefit to qualitative evaluation of solar cells defects. Radiation emitted by the solar cell has a wave character. This fact brings the potential of using some of the characteristics of the waves. We are talking about the intensity and mainly about new characterization by polarization during the detection of defects in the solar cell surface. Innovation of the measuring workplace of the standard electroluminescence method to use polarization analysis is one of the goals of this dissertation thesis.

The microplasma discharges in the PN junction local defect micro-regions are as a rule, accompanied by the emission of light. This radiation from solar cell PN junctions was measured by means of a optical fibre connected to the optical input of a photomultiplier. By inching the fibre by means of computercontrolled X-Y plotter above the cell surface a 2-D image of the irradiation local regions has been created. It is seen that a cell of a superficial area of 100 square cm contains a large number of defects, which depends on applied reverse voltage. This method can be a convenient tool for study and diagnostics of optoelectronic devices.

The restoring sources of energy and their development brings the question how these sources can be utilized in the best way. Master`s thesis deals with photovoltaic systems. It describes their history line, actual situation and also brings some expectations in the future. There are mentioned some materials and technologies which are used for its manufacture, conditions of using in practice, advantages and disadvantages and finally a real mobile application of photovoltaic which serves for a production of electricity that is saved in the battery.

This work deals with measuring of very low temperatures during the detection defects of solar cells by photoluminescence method. Liquid nitrogen is used to cooling solar cells. Properties of liquid nitrogen and safety of handling are described in this work. Themperature in cryo area is measured by the thermocouple senzors. A main part of this work was to concept and creation of equipment for themperature controling in cryo technique. This equipment signalling danger scorch in low temperatures. The device was created to complement work place for the detection defects of solar cells by photoluminescence method.

This master’s thesis deals with light induced degradation problems. In theoretical section it describes essentials of PN junction function and next light induced degradation mechanisms of solar cells and its symptoms at solar cell operation. In practical section it deals with set of measurements of solar cells since production of the silicon wafer to the complete solar cell. Selected cells are submitted to light induced degradation, measured dependencies are then evaluated. Degraded samples are subsequently recovered by two ways at high temperature treatment. The issues are evaluated.

This work is aimed to design power supply for nodes of wireless sensors networks using solar energy in indoor spaces. The proposal is made for the particular layout, but the process described can be applied generally. The result is the proposed involvement of the operating power circuit for node of wireless sensor network used indoors.

This thesis is focused on the area of analysis and diagnostic of monocrystalline solar cells, using local light radiation. Main goals of this thesis are focused on explanation of generation and behavior microplasma in solar cell, in dependence of temperature and reversed bias voltage. As a next focus of this thesis is strong regions of microplasma sources, analyzed by scanning electron microscope and a detailed analysis of edge and surface structure is made. The influence of the environment (air pressure, level of vacuum and nitrogen gas) on the microplasma generation and behavior is observed in the vacuum chamber of electron microscope. The results from microplasma method are correlated with noise diagnostic method and on the base of these results are set a new thesis and mathematical equations for the defects behavior in different conditions. The outcomes of the research are shared with the manufacturer od silicon solar cells, Solartec s.r.o. company. It is the advanced diagnostic methods that allow improving the quality of the production process, through early detection of individual groups of defects.

This thesis describes the deposition of nanoparticles into nanoporous alumina templates. Nanoparticles of cadmium sulphide were chosen thanks to wide band gap of 2,45 eV. CdS is desired semiconductor promising better efficiency when comes to solar radiation conversion to useful energy. Theoretical part consists of explanation of photovoltaic principles, band-gap theory of materials, currently available technologies to manufacture solar cells and their efficiencies. Next part introduces the approaches of manufacturing nanoporous templates from aluminium (Anodized Aluminium Oxide, AAO) in details together with options to deposit cadmium sulphide into these structures. There is also brief description of deposition based on vacuum filtration. Experiments were made in Laboratory of Microsensors and Nanotechnologies at Faculty of Electrical Engineering and Communication in Brno University of. The experimental chapter describes manufacturing process of AAO and deposition via vacuum filtration. Samples were evaluated by Scanning Electron Microscopy.