Analysis and Control of Pseudo Quadratic Buck-Boost Converter

This paper presents a common ground based pseudo quadratic buck-boost converter. Compared with the quadratic buck-boost topology, the proposed topology can realize high voltage transformation ratio with lower peak voltage stress on switching devices. Additionally, the proposed topology exhibits continuous input current, and it results in lower peak to peak magnitude of ripple current in the source side. The voltage transformation ratio and the passive components design expressions are formulated by using steady-state time-domain analysis. Using the small-signal linearization, the control-to-output voltage transfer function is derived and later utilized in the digital voltage-mode controller design. The steady-state and the closed-loop performance for pseudo quadratic buck-boost topology are demonstrated through PSIM simulation results and the circuit experiment results.