Comparative Analysis of Buck-Boost Inverters Based on Unfolding Circuit Versus H5, H6, HERIC Topologies

This paper presents the comparative analysis between the buck-boost inverters based on the unfolding circuit and H5, H6, Highly Efficient and Reliable Inverter Concept (HERIC) inverters. The components design guidelines are presented for each topology. A simple open-loop system was chosen for a verification. The comparison contains 4 criteria: an overall inductances energy, an overall capacitor energy, a total voltage stress on semiconductors and conduction losses of semiconductors and the passive elements. The main advantage of the traditional H5, H6 or HERIC topologies is a simplicity of the operation and freewheeling states. However, conventional solution produces a high leakage current, which should be reduced by the additional switches or the common-mode choke. Buck-boost inverters based on unfolding circuit have more conduction losses, but they require fewer passive components and produces small leakage current.