A Novel DC-DC Converter with Extended Range of Gain for Buck-Boost Applications

The present investigation proposes a DC-DC converter that can act as a buck-boost converter with an extended range of gain. The conventional buck-boost converter provides a high gain around unity duty ratio; however, the inductor is shorted to the source resulting in capacitor discharge to the connected load. This problem is addressed in the proposed converter, using two MOSFETs and two diodes. The count of other circuit components remains the same as a conventional buck-boost topology. A detailed analysis of the converter, including switch realization, gain formulation in both ideal and non-ideal conditions, design aspects, and controller for closedloop operation, is presented. The proposed converter can act as a synchronous converter if the diodes are replaced with MOSFETs. The same converter can be used for AC load application if all the semiconductor switches are replaced with four-quadrant switches. A MATLAB simulation study of the converter is performed, and related waveforms are presented in this paper. A hardware setup is in progress for the practical validation of the proposed converter.