Simplified Input-Output Linearizing and Decoupling Control of Wind Turbine Driven Doubly-Fed Induction Generators

Nowadays the variable speed constant frequency wind turbines with doubly-fed induction generators (DFIG) have been widely used in the wind power generation system. Vector control is introduced to the DFIG control strategies, which decouples DFIG active and reactive powers, and achieves good performances in the wind power system. However, decoupling is still present, when the flux varies. Moreover, the feedforward decoupling scheme, which plays a significant role for decoupling objective in vector control, is vulnerable to the DFIG parameters. This paper addresses a non-linear control algorithm based on the simplified input-output linearizing and decoupling control strategy. Both rotor side controller and grid side controller are presented. Finally, the control strategy is implemented and tested in a 160 kW wind power test rig, and the experiment results validate that the simplified input-output linearizing and decoupling control provides improved dynamic responses and decoupled control of the wind turbine driven DFIG.