This paper deals with the research of dynamics of a semiconductor converter, which represents a link in an automatic control system. First, we describe mathematically the circuit of the boost converter open loop, introducing a method for obtaining a model of the system under study using the state-space method. For the sake of convenience, we used controller canonical form of the state-space equations. Then we simulate it Matlab/Simulink using both the transfer function of the converter and the state-space model. After that, we switch to a closed loop modeling of the boost converter. A comparative analysis of the converter's models created using both transfer functions and state-space method shows a good performance and applicability to control system synthesis. Consequently, the control system developed provides appropriate response and desirable steady-state output voltage. The design of the system is particularly relevant for application in modern power supplies load simulators as well as in controller tuning.