Study of High Step-Up Gain DC-DC Converters Based on Stacking of Non-Isolated Topologies

Abstract


 This paper approaches the study of stacked DC-DC converters with high step-up gain, using low-voltage devices. The proposed topologies are generated from the stacking of conventional buck-boost structures and they are suitable in applications that a high conversion ratio is required. The stacked converters can also be employed as DC bus to provide one or several output voltage levels with self-balancing, and thus different loads can be connected to one or more capacitors of the stack. A generalized theoretical analysis of the proposed topologies approaching static gain, voltage and current stresses on the main components and power flow analysis is described in this paper. A 1-kW prototype with 100 V input voltage and 400 V output voltage was designed, built and tested. The experimental results corroborate the generalized theoretical analysis and they demonstrate the feasibility of the proposed converters.