Duty Cycle Based Model Predictive Control With Hexagonal Virtual Voltage Vectors for Grid-Tied Generation System With the Six-Switch Converter

The application of duty cycle-based finite control set model predictive control (FCS-MPC) to the six-switch converter (SSC), a reduced switch count multiport converter, faces the drawback of an asymmetrical and limited set of voltage vectors, which deteriorates the quality of the system currents. To overcome this issue, this article proposes an FCS-MPC technique with duty cycle optimization for a wind energy system comprised of SSC, induction generator, and grid connection, for variable speed applications. The main contribution of the technique is the use of a hexagonal set of virtual voltage vectors. Analysis of the experimental results verifies how the proposed technique reduced the grid current THD by over 60% when compared to the equivalent duty cycle-based FCS-MPC without the hexagonal voltage vectors. Additionally, the machine torque ripple factor and the grid active power ripple factors were also reduced. As a result, the proposed control technique boosts the application of the SSC in renewable household wind energy systems.