Theory of this work covers the conversion of a conventional vehicle into an electric one. It shows the advantages and disadvantages of an electric car and it describes the fundamental components which enable the conversion. This work also covers the practical part, the replacement of an internal combustion engine with an electric motor. The third part describes the working principles of buck (step-down) and boost (step-up) converter. The theoretical part is supported by simulations which are produced in software package Simplorer 7.0. This section also provides a theoretical description of bidirectional converter. The aim of its simulation is to present an insight into two-way energy flow which occurs in an electric car. Simulations demonstrate the work of transistors enabling the buck or boost modes, which, in a real drive, would signify battery charging and accelerating or keeping the speed constant. Components used in a practical performance are also described. In addition, two ways of generating a control signal are shown. The first version uses set UC3854, the signals of which have been reinforced with CD401O9B so they can include transistors. Measurements demonstrate that the signal quality will be influenced by the reference point selection. In the second version of generating a control signal, microcontroller with Cortex M4 microprocessor was used. On a separate experimental board, there was a power supply performed by means of batteries. Furthermore, a voltage divider with a range of 0-3.8 V was made. The purpose of a potentiometer is to simulate a torque sensor. The duration of a control signal is regulated by rotating a potentiometer, which at the same time affects the rotational speed of electric machine. The microcontroller is programmed in ARM Cortex M package. A code enables the analog-digital conversion because the signal of a potentiometer needs to be processed with a microcontroller and connected so it can affect the load factor.