Coordinated reactive power control of DFIG to improve LVRT characteristics of FSIG in wind turbine generation
In almost all European countries, the penetration of wind power systems and the wind turbines size continuously increases. Therefore, the grid code requirements are more and more restrictive concerning the necessity that the wind turbine to remain connected to the grid during a fault situation. This paper analyzes the possibilities to have more accurate wind generation transient stability models for fixed speed wind turbined and variable speed wind turbines. Wind system using a fixed-speed wind power generator SCIG (FSIG) cannot stay connected to the grid during faults because they cannot deliver reactive power causing a voltage drop and even voltage instability. To respect the recent grid codes and to improve the low voltage ride through capability of fixed-speed wind power generatorthis paper proposes a new control capability of PI technique method for a variable-speed wind power doubly-fed induction generator located close of the grid. The proposed control method of both grid-side converter and rotor-side converter enables the doubly fed induction generator to regulate the reactive power consumed by the fixed-speed wind power generator. The results of the simulation confirmed the theoretical wind turbines operation.