Method and system of positive and negative sequence rotor currents control for doubly-fed induction generator-based wind turbines under single dq-pi control structure

Abstract

A method and system of positive and negative sequence rotor currents control for DFIG-WTs under a single dq-PI control structure includes: adjusting the negative sequence rotor current reference according to the negative sequence stator terminal voltage to obtain a reference adjustment value; converting the reference adjustment value to the forward-rotating dq coordinate system and superimposing it with the positive sequence rotor current reference as the input of a PI-regulator-based current feedback controller to uniformly control the positive and negative sequence rotor current; determining the output voltage reference of the rotor-side converter by the PI-regulator-based current feedback controller, according to which, the switching signal of the rotor-side converter can be determined through the SPWM function, controlling the turn-on and turn-off of the bridge arms of the rotor-side converter to form the output voltage.{right arrow over (Ī)}