In recent years, the interest for parallel multicell converters has grown, which is partially due to the possibility of coupling the inductors used to connect the different commutation cells together. Coupling the inductors to form an InterCell Transformer (ICT) does not usually modify the output current, but it reduces the current ripple in the windings and the flux swing in some regions of the core. It can be shown that this brings a reduction of copper and core losses in the magnetic component. The reduction of the phase current ripple also reduces the difference between turn on and turn off current in the switches, which brings a reduction of switching losses for devices generating more losses at turn off than at turn on. The design of an ICT is not that different from any other magnetic component but it is very specific and inherent features must be taken into account. Taking full benefit of the potential advantages of ICTs requires the development of special tools and methods which are the focus of the study. We show how to design ICTs considering several topologies and different methods, from the most precise and time-consuming to the less accurate but more quickly calculated. The explanation of the ICT design is divided in four main parts: Copper Losses, Core Losses, Flux Density Saturation and Thermal Aspects. Further attention is given to high frequency copper losses since complex phenomena such as skin and proximity effects highly influence the ICT design. Based on Finite Element Method simulations, smart practices are suggested to reduce high and low frequency copper losses, not only in ICTs but also in inductors and transformers. Simple tables are developed to help transformer designers to identify the best configuration of conductors inside a given core window, depending on the current waveform and frequency, number of turns and geometrical parameters. Optimization routines to reduce the ICT total mass, volume, losses or cost are developed and multidimensional interpolation of pre-simulated values of AC resistance and leakage inductance is used to speed up the optimization routine. Comparison of ICT designs with regard to core and conductor material, number of cells and switching frequency is performed. Comparison with regular inductors is also made in order to verify the benefits of this kind of magnetic component. Multilevel converter control aspects applied to three- hase systems is also investigated in terms of the ICT flux. Zero sequence signals, specific for a PWM strategy and converter/load topology, are created in order to minimize the flux in ICTs and consequently reduce even further the mass and size of these components. Comparison between several PWM methods are performed and experimentally verified.

High efficiency of power converters placed between renewable energy sources and the utility grid is required to maximize the utilization of these sources. Power quality is another aspect that requires large passive elements (inductors, capacitors) to be placed between these sources and the grid. The main objective is to develop higher-level high frequency-based power converter system (HFPCS) that optimizes the use of hybrid renewable power injected into the power grid. The HFPCS provides high efficiency, reduced size of passive components, higher levels of power density realization, lower harmonic distortion, higher reliability, and lower cost. The dynamic modeling for each part in this system is developed, simulated and tested. The steady-state performance of the grid-connected hybrid power system with battery storage is analyzed. Various types of simulations were performed and a number of algorithms were developed and tested to verify the effectiveness of the power conversion topologies. A modified hysteresis-control strategy for the rectifier and the battery charging/discharging system was developed and implemented. A voltage oriented control (VOC) scheme was developed to control the energy injected into the grid. The developed HFPCS was compared experimentally with other currently available power converters. The developed HFPCS was employed inside a microgrid system infrastructure, connecting it to the power grid to verify its power transfer capabilities and grid connectivity. Grid connectivity tests verified these power transfer capabilities of the developed converter in addition to its ability of serving the load in a shared manner. In order to investigate the performance of the developed system, an experimental setup for the HF-based hybrid generation system was constructed. We designed a board containing a digital signal processor chip on which the developed control system was embedded. The board was fabricated and experimentally tested. The system’s high precision requirements were verified. Each component of the system was built and tested separately, and then the whole system was connected and tested. The simulation and experimental results confirm the effectiveness of the developed converter system for grid-connected hybrid renewable energy systems as well as for hybrid electric vehicles and other industrial applications.

No description available.

This thesis deals with the history of a method of plants cultivation without original substrate. The method is hydroponics and its subsequent development is called aeroponics. This work outlines the design of the whole aeroponic system including a control unit. The control unit has been designed to control the injection of nutrient solution, which is essential to the life of plants.Further, the control unit performs the control of lighting period, temperature, air flow and also regulation of nutrient solution pH. The control unit also keeps records of all data necessary for the monitoring process and for the evaluation of time differencies in the system.

This master’s thesis deal with principles temperature measurement using resistive temperature sensor PT100 and algorithm design PSD controler. In Work is includ description problems temperature measurement and way evaluation by means of mikrokontroler, which by PWM output controls supplied heat power. Next is here described method realization controls device for heating electric furnace with setup via Ethernet.

This thesis deals with the history of a method of plants cultivation without original substrate. The method is hydroponics and its subsequent development is called aeroponics. This work outlines the design of the whole aeroponic system including a control unit. The control unit has been designed to control the injection of nutrient solution, which is essential to the life of plants.Further, the control unit performs the control of lighting period, temperature, air flow and also regulation of nutrient solution pH. The control unit also keeps records of all data necessary for the monitoring process and for the evaluation of time differencies in the system.

This master thesis deals project and realization of universal transistor converter for power electronics course. For this converter was at the same time designed control circuit and drive circuit. Next part is about the design of compact converter for DC. This converter is controlled by a microprocessor Freescale.

This text analyzes characteristics of audio power amplifiers in class D. The emphasis is placed on more detailed analysis of modulators, drivers, connection topology of power transistors. In the next section of text are analyzed available integrated circuits of power amplifiers in class D which are manufactured by world producers. The last part describes design of all parts of amplifier in class D with discrete components and also of power supplies. According to the plans, the individual parts are made. All parts are tested by measurements and results are evaluated.

The aim of this thesis is to design and implement an industrial programmer AVR microcontrollers from Atmel. The first section provides the theoretical knowledge of the AVR microcontroller. Furthermore, comparison of methods for programming the microcontroller and the selected method is an analysis of the speed of programming. The following is the entire design of industrial programmer which is implemented in the programming environment Eagle. In the penultimate part of the proposal is designed PCB. The final section is devoted to the revival of the programmer and programming.

This master‘s thesis deals with applications for tablets running Android to control the car. As a control unit is used Raspberry Pi with Edimax WiFi module. The practical part focuses on the realization of applications for tablet and board layout for switching lights.