This work deals with theory of switched power sources. There is description of the ways for connection and their practice purposes. In the next parts there are defined requirements on input supply circuit for these sources, especially for the form of output current. There are mentioned the basic connecting methods of PFC circuits and these methods modify the output current to meet the requirements of specification ČSN EN 61000- 3- 2. In the next parts there are shown simulations of PFC circuits made by Pspice application. Further is the basic description of sources construction for the sources which were used for testing and measuring. The final part deals with evaluation of the measuring on the chosen computer’s source. It compares between the manufacturer’s solutions and PFC circuit made by ourselves.

This work is concerned with power inverters for alternate high voltage power sources. The theoretical part describes the topology of inverters that can be used in alternate power sources. A model of voltage transformer is described in details to better understand the parasitic effects that are inevitably present in high voltage power sources and, therefore, have to be taken into consideration at the design of high voltage power sources. The work is oriented to problems of alternate high voltage power sources for ozone generators. This is the reason, why the theoretical and, partially, also the experimental part deal with the properties of ozone and its use. The experimental part solves high voltage inverter with capacitive load that is formed by discharge element of an ozone generator. Designed inverter is able to feed the capacitive load with high voltage at very short periods of time from several microseconds up to tens of nanoseconds. In comparison with the length of voltage pulses in common ozone generators, this pulses are more than 100-time shorter. This has a positive effect to silent discharge characteristics.

This master thesis is focused on proposition and following implementation of DC arc welder. This paper is based on semester’s paper, where the first version was realized. The welder is powered by a battery pack with LiFePO4 type cells. Battery cells are protected by BMS circuits. The driving electronics controls the duty cycle step-down (buck) converter in a closed current or power regulation loop. The power regulator has been designed and validated by simulations. Switching power transistors, low side and high side, are implemented by optically isolated gate drivers. Charging the battery is solved by a switching flyback converter. For the charger and the welder is sheet metal construction made of aluminum sheet.

The master’s thesis is focused on the creation of models of DC/DC converters and control program for input parameters and their configuration. The first part is theoretical and she is dedicated to the description of the program Matlab. The second chapter is dedicated to DC/DC converters. Their function is described there and the necessary equations for the design are derived. All of this is complemented by the calculation of line losses in semiconductor elements and the design of voltage and current regulator. The last two parts deal with the description of the created models in Simulink and control program in a graphical environment. The created program is able to edit and recalculate parameters of the converters, calculate line losses on semiconductor components, perform a model simulation or open it.