A Common Ground Buck-Boost PFC Converter with Quadratic Voltage Gain Ratio and Integrated Active Power Decoupling Capabilities

This paper presents a new high-voltage-gain, common-ground power factor correction (PFC) active rectifier. The proposed power converter offers several advantages, including a quadratic voltage gain ratio that surpasses both common-ground and non-common-ground buck–boost PFC converters. It also incorporates an integrated active power decoupling method to reduce the size of the dc-link capacitor. The design ensures continuous input current for high-quality input power, while utilizing only five switches. With a common ground between the input ac source and the output dc load, the converter effectively mitigates electromagnetic interference (EMI) associated with rapid voltage changes, thereby reducing the need for EMI common-mode filtering. Furthermore, a new two-loop deadbeat control system is introduced to efficiently regulate both the inner and outer control loops. Experimental results from a 500 W prototype validate the rectifier's performance in both step-down and step-up ac–dc power conversion. Operating from a 110 Vrms input, the prototype achieves 80 Vdc and 180 Vdc outputs, with peak efficiencies of 97.0% and 96.9%, respectively.