Digital MPPT technique for PV panels with a single voltage sensor

This work reports the results obtained using the SEPIC converter as an MPPT (Maximum Power Point Tracker) interface for photovoltaic systems employing a single voltage sensor. The MPPT algorithm is based on the variation of the input static characteristic impedance of a SEPIC converter fed by a photovoltaic panel. Although the SEPIC input impedance theoretically depends on its load resistance, it is shown that employing the proposed algorithm leads to the maximum available power being delivered to a large load resistance range without previous knowledge of its value. The validation of the proposed MPPT technique is given based on numerical simulations performed in PSIM by emulating a microcontroller based algorithm through a DLL (dynamic link library) program and experimental results.