Fast Voltage-Based MPPT Control for High Gain Switched Inductor DC-DC Boost Converters

Switched inductor (SL) step-up dc-dc converters can be used for high voltage gain applications such as in PV systems. In this paper, a study of a N-cell high voltage gain boost dc-dc converter performing maximum power point tracking from a PV source is presented. First, the time domain dynamic model is derived. Then, the linearized s— domain model is first obtained. It is obtained that contrarily to the conventional canonical boost converter, the N–cell switched inductor converter presents a stable zero in the duty-cycle-to-PV-voltage transfer function which can be considered as an advantage to design a fast voltage-based MPPT control having the same response speed that corresponds to current mode control. Using the resulting control-to-output transfer function, a fast voltage-based MPPT controller is designed. Finally, numerical simulation are used to evaluate the performances of the converter when used in PV applications under different weather conditions.