High performance steady state modeling & controlling algorithm for DFIG

The paper describes a novel steady state technique for high performance wind-driven DFIG. The analytical models are carried out in both of synchronously rotating frame and stationary reference frame. A detailed analysis of the overall performance of the DFIG operating at the steady state variable speed operation using both frames are investigated, compared and evaluated. Unlike other works, the model takes stator resistance, mechanical power, developed power and net generated power (in its ac and equivalent dc forms) into consideration. This relation maps the relationship between turbine, generator and grid (or load in stand-alone systems) sizes. Power distribution to (or from) the grid is presented using three different analytical models to evaluate the proposed strategy. Further active and reactive power control has been achieved via the load angle control. The developed control system offers two control strategies of rotor voltage vector control and rotor current vector control via the rotor PWM voltage source converter.