Modeling of a Quadratic Buck Converter Based on the R2P2 Concept for PV Applications

In photovoltaic systems, it is necessary to have DCDC converters topologies with wide transformation ranges that have the ability to provide output voltages that can be greater or less than the supply voltage by the PV modules. Other aspects that these converters must satisfy are associated to the new requirements of the load consumption. These requirements have been standardized to 48V, 24, 12V and 5V for different applications such as LED lighting, battery banks, amongst others. Also, one important requirement in these systems is that the power processing by the converter must be carried out as efficiently as possible. This paper presents an implemmentation of a quadratic buck converter based on the concept R2P2 as an alternative for photovoltaic applications, where the characteristics of the input current demanded to the panels and the reduction of EMI are improved. In this work, the description of the system formed by the quadratic buck converter R2P2 with an input filter is analyzed, where the requirements of non-pulsating input current and output voltage regulation are satisfied. In addition, the design procedure of the elements that form the converter is developed, as well as the description of the operating modes during the switching process of the converter. Finally, the linear and non-linear models of the converter are presented, as well as some comparative aspects against proposed topologies and the experimental verification.