A variable structure approach to control the active and reactive power for doubly fed induction generator

Abstract

The original direct power control (DPC) is known to give a fast response under transient conditions. However, active power, reactive power and current pulsations occur in steady-state operation. A family of variable structure controllers for the doubly fed induction generator (DFIG)-based wind turbine system is presented, using the principles of an active and reactive power controller known as modified DPC, and where variable structure control (VSC) and space-vector modulation (SVM) are combined to ensure high-performance operation. VSC scheme is designed following the modified DPC philosophy, which provides robust, fast, accurate active and reactive power controls without the problem of high chattering. Simulation results demonstrate that the proposed method preserves the effectiveness and robustness during variations of active and reactive power, rotor speed and converter DC-link voltage.