Fully FPGA based direct model predictive power control for grid-tied AFEs with improved performance

Single-switching-vector-per-sampling-interval character of the classical Direct Model Predictive Power Control (DMPPC) technique leads to big ripples of the control variables. Therefore, with a similar sampling frequency, its steady state performance is not satisfying. This work proposed a Revised Direct Model Predictive Power Control (R-MPDPC) concept for grid-tied AFEs. Instead of one single switching vector, two adjacent vectors are utilized to minimize a modified cost function based on time-optimal concept, which yields a synthesized equivalent voltage vector with an arbitrary phase. Therefore, more freedoms and precise tracking possibilities are included into the predictive controller design. The proposed control scheme is realized with a fully FPGA based solution on a lab-constructed AFE platform. Its performances are compared with the classical DMPPC with all experimental data. The results confirm that the control performances are greatly improved using the proposed R-DMPPC scheme.