A simplified analysis of DC-DC converters applied as maximum power point tracker in photovoltaic systems

Maximum Power Point Trackers (MPPT) systems are essential devices employed to maximize the power flow from a photovoltaic module (or array) to a load. In most applications, the MPPT is composed by a DC-DC converter interposed between the photovoltaic module and the load. Among the main DC-DC converters, the Buck-type and Boost-type are not proper for this purpose, since they cannot ensure that the operation point will match the maximum power point for every radiation and temperature conditions. On the other hand, as it will be demonstrated theoretically and by experimentation, the Buck-Boost, Cúk, Sepic, Zeta, or any other DC-DC converter with static transfer characteristic given by D/(1-D), are a natural solution in Maximum Power Point Tracking applications.