Universal Delay Compensation for Model Predictive Current Control of Three-Phase Inverters

Finite control set model predictive control (FCS-MPC) approach is highly dependent on the system model. It is equipped with the advantages of simple structure, high accuracy and optimization performance. When considering the model uncertainties, control performances are inevitably degraded to some extent. Time-delay is a typical kind of model uncertainties, which significantly affects the prediction accuracy and system stability. In this paper, a fractional-order based Smith Predictor based composite FCS-MPC approach is investigated and applied in a grid-connected system. The control accuracy can be significantly improved in this way. Moreover, considering the inherent time-delay introduced by Smith Predictor, phase lead design solution has been proposed. Various cases of simulation results are illustrated to show the effectiveness of the investigated approach.