A Model for Processed Power in DPP Converters

Differential power processing (DPP) converters have recently been utilized in solar PV systems to eliminate partial shading losses in series-connected PV modules. A significant advantage of DPP systems over other distributed converters is their relatively small power rating, which is usually a fraction of the rated power of the corresponding PV module. However, selecting the appropriate size for a DPP converter remains a challenge, necessitating a trade-off between converter cost and savings in power losses. Currently, there is no model for accurately determining the required rating for a DPP converter to effectively eliminate power losses. This paper introduces a set of equations for DPP systems connected in a PV-PV architecture, capable of estimating the processed power in DPP converters under any shading scenario. The paper offers a tool for researchers and power electronics to optimally size DPP converter based on the counter shading scenarios. It also highlights key factors influencing the DPP rating. Extensive simulations and verifications are presented to validate the proposed method for determining the optimal size.