Hybrid vector-based predictive current control strategy for three-phase L-shaped grid-connected photovoltaic inverters

With aims to address the problems of high total harmonic distortion (THD) and incomplete voltage vector control range of the traditional two-vector and three-vector grid side current control, this paper proposes a hybrid multi-vector predictive current control strategy (HMPC). The control strategy merges the optimum combined voltage vectors from two-vector and three-vector control. These two voltage vectors serve as the fundamental variables for the predictive current control of the two-vector model, which predicts the current’s future value. Technical term abbreviations will be defined upon first use. The strategy comprises of four essential voltage vectors per control cycle (three effective voltages for bi-vector control and one for tri-vector control). At a reference current of 10A, the current harmonic distortion rate of the hybrid multivector control is lower than that of bi-vector and tri-vector controls (2.98% for bi-vector, 2.48% for tri-vector, and 1.13% for hybrid multivector), making it more robust.