A control strategy of induction machine to be used as generator in cogeneration plants in stand alone operations

The energy management is becoming more and more important in recent years, especially with the spreading of distributed power generation plants. The possibility of the generation system to work in stand alone mode represents a chief characteristic that makes one system preferable with respect to others. The induction machine, that seems to be the optimal solution for the generation grid connected, presents some problems when working stand alone. In this paper the induction generator in stand alone operations is analyzed. By means of analytical model the conditions necessary to realize an autonomous network are discussed. The influence of the saturation of magnetic circuits and the power limit of the generation system have been evidenced. Results of numerical simulations are reported.