Transformless Single-Switch Buck-Boost DC-DC Converter with Inverted Output Voltage

This study introduces an innovative transformerless buck-boost converter capable of generating a negative output voltage. The design features a straightforward structure and offers an extensive range of conversion ratios. A high step-up voltage gain can be attained with a moderate duty cycle and utilizes only a single switch, making its control relatively simple. This paper delves into the operational principles, conducts a thorough steady-state analysis, and explores the proposed converter's small-signal modeling specifically within continuous conduction mode (CCM). A comparison study is provided between the proposed converter and various existing buck-boost converters. Additionally, variations of the proposed converter are introduced. To validate the theoretical analysis, simulations were conducted using PLECS software, and a laboratory prototype was developed.