Predictive Current Control Strategies for Grid Connected NPC Converters

This paper analyses predictive current control techniques for grid-connected neutral-point clamped voltage source converters. Two schemes are considered, the classical finite-set model-based predictive current control (FS-MPC) along with a new strategy designed to operate at fixed switching frequency. The performance of these schemes are compared taking into account the regulation of the control criteria along with figures of merit for the application considered in this work. The assessment is conducted by means of simulation results. Both schemes presented high-performance for renewable energy integration. The balance of the dc bus is slightly superior by using the FS-MPC, whereas the current quality and the spectrum characteristics are improved with the developed proposal.