A Common Grounded Zeta-Canonical Switching Cell Single-Stage Buck-Boost Inverter

This article proposes a single-phase single-stage nonisolated buck-boost inverter for photovoltaic systems. It is obtained by combining and reconfiguring two dc-dc circuits, Zeta and canonical switching cell (CSC). In the proposed inverter, Zeta and CSC will operate alternately at positive and negative half cycles, respectively. The common mode leakage current is eliminated due to the fact that there is a common terminal in the input and output ports in both modes. Besides, only one switch operates at a high frequency in each mode, resulting in high efficiency. This article first introduced the derivation process of the proposed inverter and its operation principle. Then, the controllers and inverter parameters in both modes are designed. Finally, its performance is verified with a 500-W laboratory prototype.