Passivity Based Control of Doubly-Fed Induction Generators in Wind Turbines

This paper presents the evaluation of a passivity based control (PBC) strategy for doubly-fed induction generators having wind turbines as prime movers and operating connected to a power network. The evaluation is intended to demonstrate that a PBC strategy initially designed to control generation at unity power factor can control power exchange at a fixed active power delivery to the grid with different power factors. The system model assumes a wind flow of constant kinetic energy and hence a constant mechanical torque in the turbine shaft. The power network is modeled as an infinite bus connected through a line-impedance to the generator terminals. The obtained results show that the PBC strategy is simple and effective and that the active and reactive power exchange with the power system can be adequately controlled.