National Repository of Grey Literature 134 records found  beginprevious21 - 30nextend  jump to record: Search took 0.00 seconds. 
Oxygen cycle during pulse charging of lead-acid accumulator
Havlíček, Jiří ; Vaněk, Jiří (referee) ; Křivík, Petr (advisor)
This master´s thesis applies to puls charging of lead-acid accumulator and arising oxygen cycle while charging. First part of the thesis is focused on potential dividing of lead-acid accumulators and their construction. I also focus on priciples of submerged electrodes accumulator, gel accumulator and AGM accumulator based on oxygen cycle. The next topic are thermal and degradation processes inside accumulators and their influence on capacity and lifespan. In theoretical part am I describing ways of charging and I also point out possitives and negatives. Practical part focuses on producing experimental cell and its form. Experimental cell is tested to different modes. I evaluate their influence on temperature inside the cell, intensity of oxygen cycle and capacity. I compare their influence on duration of charging cycle to another possible charging modes.
Analysis of thermal processes inside of lead acid battery cell in oxygen cycle regime
Vondrák, Michal ; Bača, Petr (referee) ; Křivík, Petr (advisor)
The aim of this thesis is the analysis of thermal processes in lead accumulators with oxygen cycle. The work is explaining the structure and principle of operation of the standard lead-acid battery and lead-acid battery with oxygen cycle. Generally are described thermal action inside a lead battery with oxygen cycle and the different types of heat generated during operation of the battery are discussed in detail. One chapter describes the practical experiments and their results.
Pulse charging of lead-acid accumulator using negative current steps
Kantor, Pavel ; Vaněk, Jiří (referee) ; Křivík, Petr (advisor)
The lead-acid batteries are the most commonly used electrochemical power sources and are the oldest type of secondary battery cells. This master thesis provides a short introduction to the lead-acid batteries and shows possible ways of sorting from different points of view. Thesis describes construction of lead-acid batteries, parameters of lead-acid batteries, electrochemical and physical reactions inside the battery. Futher the thesis deals with pulse charging of lead-acid batteries. In the next part of the thesis is described the production of a set of experimental electrodes for electrochemical workplace resources. The final part of this thesis are experiments focusing on the pulse charging using negative current pulses and evaluate the effect of different pulse modes on cells.
Inovation of system for electroluminiscence defect detection of solar cells
Lepík, Pavel ; Křivík, Petr (referee) ; Vaněk, Jiří (advisor)
This master thesis analyses the existing methods both practically and theoretically used to detect defected surface area in solar cells. Various methods were used but by using an upgraded CMOS camera without IR filter to implement the electroluminescence method, this has proven to have a very crucial impact on the results. Given the overall results and the acquired information, a procedure with a simple parameter can be setup to carry out the measurements. In addition to this a catalog was formed showing the defects occurring in mono and polycrystalline solar cells.
Impedance spectroscopy measurements in lead acid batteries
Holemář, Jan ; Bača, Petr (referee) ; Křivík, Petr (advisor)
The master thesis provides a brief introduction to the lead-acid batteries. The thesis describes an internal construction, electrochemical reactions inside the batery, the area of application and possible degradation effects. The next part deals with an analytic method of the measurement called electrochemical impedance spectroscopy. The thesis describes the principle of measurement, alternative equivalent circuits, the impedance of electrochemical cell and the analyse of recorded datas. In the practical part was assembled the functional lead-acid cell. After that, experimental measurement was passed on the lead-acid cell in discharge and in a different concentration of electrolyte. In the last part was created the simulation of treatment of an electrochemical cell in the development solution Agilent VEE and after that all the measurement results were compared with the simulation.
Creation of laboratory exercises for Renewable sources of energy
Bajgl, Tomáš ; Jandová, Kristýna (referee) ; Křivík, Petr (advisor)
This diploma thesis deals with the transformation of solar and wind energy into electrical energy by using a photovoltaic panel and a wind turbine. The work gives insight into the Czech Republic’s issue of energetics in the context of historical development, the current state, and the expected future development. The primary attention is given to the renewable sources - the solar energy and wind energy. Basic principles of creation and manipulation of solar and wind energy are described in this work. Two laboratory tasks are created for the Renewable Energy Sources' class as a part of the practical part.
Analyzing of measured solar spectrum
Štěpánek, Jakub ; Křivík, Petr (referee) ; Vaněk, Jiří (advisor)
This diploma thesis deals with the definition of solar lights for solar purposes and solar simulators. These concepts are presented and described in detail. The theoretical part is described below chapter explaining the possibilities of using solar energy phototherapy. The next section follows the issue of standards and their podnorem AM, describes in detail the direct and diffuse light component. In connection continues with IEC 60904, IEC 60904-3 and IEC 60904-9, differences in purpose and use. The thesis describes the problems of the methods of analysis of the solar spectrum as defined in IEC 60904-9. In the penultimate chapter we discuss all light sources, their properties and uses. They navyzují selected light sources used in this work, as well as descriptions and color filters designed for measurement and subsequent evaluation in the practical part. The last chapter analyzes used measuring instruments, their advantages and disadvantages. In the practical part, we describe a method for measuring real-world light spectra, determining compliance with these spectra spectra AM 1.5 and the necessity to generate data from IEC 60904-3. Another part allows measured data to see in an understandable form and must include an assessment and assignment of the data set into classes according to AM 1.5.
Optimalization of tilt of photovoltaic module
Šindler, Roman ; Vaněk, Jiří (referee) ; Křivík, Petr (advisor)
This thesis deals with the solar radiation, which is one of the potential sources of the renewable energy. The purpose of this thesis is to apprise of the methods how to calculate the Sun’s position as well as to learn the basics of software VEE Pro 8.0. Also, create a program simulating the location of the Sun during the day according to the variable latitudes and days and consequently to calculate the Sun irradiation passing through the atmosphere onto the tilted solar module, considering the respective tilt. Theoretical part describes the transmition of the energy between Sun and Earth, global irradiation and its components, which are generated by beams passing through the atmosphere and incident on a solar module. Practical part is dedicated to a program creation according the theoretical basis and it is used for further simulation of the Sun’s position. Another program simulates the total daily and annual irradiation including its components onto the tilted solar module, considering the respective tilt.
Mobile applications development for remote control of instrumentation
Macek, Michal ; Křivík, Petr (referee) ; Frk, Martin (advisor)
The presented work describes the growing trend of using mobile devices to control laboratory instruments and displaying of measured data. The main objective is the application development for mobile devices, which will allow to remotely control and measure with laboratory instruments. The practical part is focused to programming mobile application which will be able by using the local network to connect multiple laboratory instruments, setting them for different types of measurements and then display measured data.
I-V characteristic on photovoltaic modules connected in parallel and in serial
Láník, Lukáš ; Vaněk, Jiří (referee) ; Křivík, Petr (advisor)
In mentioned theses there are described the basic tenets of the photovoltaic panels operation. There is described the progress of the photovoltaic panels. Theses is focused on the theoretical knowledges about the equivalent circuits and their aplication in the proposed simulation system. The goal of theses is to create the surroundings in the program Agilent VEE Pro 8.0 and to create the program for the simulation of the serial and paralel conjunction of the photovoltaic panels. The resultant program enables the simulation of the I – V and P – V characteristics of the real photovoltaic panels.

National Repository of Grey Literature : 134 records found   beginprevious21 - 30nextend  jump to record:
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