Improve Power Quality of grid connected PMSG based wind energy

The quantity of energy extracted from the wind primarily depends upon the type of generator used. Presently doubly feed induction generator (DFIG) and permanent magnet synchronous generator (PMSG) are widely used in wind energy conversion systems (WECS). In a DFIG based WECS a gearbox is used to synchronize the speed of turbine and rotor. The use of gearbox makes the WECS unreliable as the gearbox requires regular maintenance and it also suffers from faults. The use of PMSG in WECS system improves the reliability of the system. The WECS system with PMSG can be employed without the gear box and its self excitation property helps it to operate at high efficiency with high power factor. PMSG has many other advantages over DFIG such as because of the absence of slip rings makes its design simpler, as it is a self excitation generator as it does not require any DC supply for excitation circuit. Because of the above functional advantages of PMSG over DFIG most of the commercial WECS with DFIG are being replaced by PMSG.