Tri-freedom Bisection Algorithm for OSV MPC of Three-phase Inverters to Improve Power Quality

When optimal switching vector (OSV) model predictive control (MPC) is implemented to a three-phase inverter, the control input is selected from eight switching vectors (vi). This set of vi has merely two-level amplitude with a 2π/6 phase difference. Higher phase or amplitude resolution of vi anticipates better power quality. This paper presents a bisection algorithm to tune the resolution of OSV for power quality improvement. Three user-defined gains (x, y, n) are provided to quantitatively set the phase/amplitude resolution of the OSV using derived explicit formulas. Experiments validate the effectiveness of this algorithm.