DMC versus Gain Scheduled PI Controller for Pitch Regulation of 100 KW Wind Turbine

In the recent years, wind energy improves to one of the most important sources of electricity production. For instance it is predicted that the installed wind capacity in China will be about 40 GW till 2020. The permanent magnet synchronous generators (PMSG) which contains a permanent magnet that causes DC excitation current in the stator windings, are widely used in variety of wind turbines. The advantages of this type of generators in comparison to the others, are higher efficiency, controllable terminal voltage and reactive power. It is also remarkable that the PMSG speed can be controlled by the converter leads to MPPT implementation. The MPPT is always implemented to control the generator speed and output power between the cut-in and nominal wind speed. It is necessary to control the generator speed by pitch or stall control for upper rated wind speeds. In this paper after explaining the structure and components of a typical wind turbine with permanent magnet synchronous generator, designing of an offline DMC (Dynamic Matrix Control) and a gain scheduled PI pitch controller are presented. Both of these controllers have been tested on the practical simulator of 100 KW wind turbine with PMSG generator and the results are presented and compared.