Robust output voltage tracking algorithm for three‐phase rectifier with variable sliding surface

In this article, a variable sliding surface-based output voltage tracking controller is proposed for three-phase rectifiers driven by the pulse-width modulation technique. A systematical multi-variable approach is used for deriving the control law, considering the not only non-linearity but also parametric uncertainties. The proposed method has two features. First, the non-linear first-order disturbance observers are introduced to enable for the control law to exponentially recover the desirable tracking performance without any offset-errors in the sliding mode. Second, the self-tuning algorithm is designed to update the sliding surface to enhance the output voltage tracking performance in transient periods. The performance of the proposed method is experimentally demonstrated by using a 3-kW three-phase rectifier.