In this paper a theory of power converters has been described with and without galvanic seperation. In the group of power converters without galvanic separation, there are buck, boost and buck-boost converter. In the group of power converters with galvanic separation there are push-pull, half-bridge and bridge converter. The theoretical part of this work is supported by simulation of a push-pull converter which are produced in the Simplorer software package. To be able to control the converters, it is necessary to generate control signals, which will control the transistor switches. The STM32F4 development system with a STM32F407VTG6 microcontroller was used when generating control PWM signals. For microcontroller programing, a Keil μVision 5 software package was used. Before writing a program code it is important to know microcontroller architecture, but it is also necessary to know well timers and counters which containes this microcontroller. Although there are existing libraries for generating PWM signals, they do not have ability to set the dead time between the two PWM signals which is necessary for push-pull converter management.