Multi-oscillatory current control with anti-windup for grid-connected VSCs operated under distorted grid voltage conditions

The paper presents a state-feedback current controller with damped oscillatory terms designed for three-phase grid-connected voltage source converters under distorted grid voltage conditions. The paper focuses on a synthesis of an anti-windup strategy for the LQ current controller. This strategy is based on an active clamping method for the proportional-integral part and the adjusting mechanism of the damping factor (AMDF) for the oscillatory terms. The adjustment uses a simple moving average method (SMA) for smoothing changes of the damping factor. The paper shows the first experimental study of the proposed anti-windup strategy for the LQ current controller with oscillatory terms.