The existing control system for aggregate 20 that consists of induction motor and two DC generators, and the new proposed control system which is based on a programmable logic controller and touch panel are described in the introductory part of this graduation thesis. The new control system for aggregate 20 is implemented on a real model in laboratory. The model consists of a squirrel cage induction motor connected to the frequency converter and synchronous generator with salient poles. Programmable logic controller operates with induction motor by exchanging control words with the frequency converter via Profibus communication network, while DC current of synchronous generator is controlled by an analog unit of programmable logic controller connected with DC digital regulator. Laboratory model is controlled by using touch panel which also provides instantaneous display of voltage, current and speed of induction motor, and instantaneous display of voltage, current and DC current of synchronous generator. Values related to the synchronous generator on the programmable logic controller are brought using the measuring transformer and clamp, while values related to the induction motor on the programmable logic controller are brought by frequency converter. Within the graduate thesis components of laboratory model are precisely described with instructions for their use. In the last chapter the important parts of control program for programmable logic controller and the program for touch panel are described.