A control scheme for two doubly fed induction machines fed by indirect matrix converter

In this paper, a topology for a grid connected generation system based on two doubly fed induction machines is presented. The proposed scheme is implemented using an indirect matrix converter consisting of an input stage and two output stages. The input stage is connected to the grid and provides the required DC voltage for both output stages. Each of the output stages is connected to the rotor of the corresponding machine. The rotor currents of each machine are vector controlled. Space vector modulation is used for the input and output stages. The switching pattern to minimize the commutation losses of the input converter and/or reduce the ripple of the indirect matrix converter input current is selected depending on the rotational speeds of the machines. Experimental results, considering the system running at below and above synchronous speed, are presented.