A New Robust Analog Maximum Power Point Tracker for a PV Battery Charger

Abstract

Maximum power point tracking (MPPT) is an inevitable part of new controller design for PV connected voltage converters used to extract energy. To simplify the implementation of the algorithm, in this paper, an analog circuit for MPPT of a PV battery charger is proposed which works in a full range condition with constant switching frequency. Besides this, a new robust controller parameter is introduced. As discussed in the paper, conventional MPPT algorithms provide PV current or voltage reference value as output controller parameter, which fast climate changes may cause system instability. Here, a new variable is defined to eliminate the problem and improve the stability of the system. To compare the presented circuit with a conventional system, perturb and observe MPPT algorithm which is well-known in PV systems is implemented on the same system. The proposed system is also compared with a recently developed current-mode system. Simulation results for both simulations are presented and compared which demonstrate performance and effectiveness of the proposed analog MPPT circuit.