Constant switching frequency finite control set model predictive control applied to the boost converter of a photovoltaic system

摘要

This paper proposes a constant switching frequency finite control set model predictive control applied to the boost converter of a photovoltaic system. The controller consists of two control loops: the outer voltage control loop employs the voltage reference generated by the MPPT and the system model to calculate the inductor predicted current reference for the converter, in order to minimize the error in the voltage at the terminals of the panel. The inner current control loop minimizes the current error to obtain a cost function calculated from the current variation rates in the inductor for the two possible states of the switch. The resulting equation gives the converter's duty cycle, thus ensuring constant switching frequency. The obtained results are compared with a two-pole two-zero controller using an experimental setup presenting a reduction in the settling time, steady-state error and overshoot, attesting the controller performance.