Pitch angle control using hybrid controller for all operating regions of SCIG wind turbine system

In the past, wind power penetration was extremely limited compared to the total power production. As a result, the interconnection requirements for wind farms were not included in the grid codes. However, in the recent years, the significant amount of energy injected by wind farms has already impacted the power system, both from a technical and a regulatory point of view in the recent years. Large wind plants have a significant influence on power system operation since they are related to unpredictability of the primary source. Thus wind turbines must improve their quality production to ensure the stability and reliability of the power system as conventional power plants. Wind energy is not constant and, since wind turbines output is proportional to the cube of wind speed, this causes the power output of Squirrel-Cage Induction Generator Wind Turbine (SCIG WT) to fluctuate. In order to improve power quality and maintain the stable output generated from SCIG wind farm, this paper presents a hybrid controller based on PI and fuzzy technique for the pitch angle controller which has been one of the most common methods for smoothing output power fluctuations. All models as well as controllers here presented are developed using Matlab-Simulink software.