Double fed induction generator with two pair of poles

This paper demonstrates that the double fed induction generator (DFIG) for two pair of poles can work successful in a wide speed range. For the examined case, it was possible to continuously generate power from 500 RPM to 2000 RPM. This is very suitable for cases when the generator is used in windmills where the speed of the rotor of the generator varies significantly, and where regulation of the speed when it is done mechanically on the propeller is very costly and complicated. It has been shown that the analysis of DFIG can be done satisfactory by simple model of the equivalent circuit which only takes in account the fundamental harmonics. By increasing the number of pairs of poles in the machine to three, it is possible to increase further the speed range. Such a machine is also easy to control. It has been demonstrated that it is possible to obtain stable working conditions by real-time control.