Achieving High Input PF for CRM Buck-Buck/Boost PFC Converter

• Main Authors: Abdul Hakeem Memon, Mazhar Hussain Baloach, Anwar Ali Sahito, Amir Mahmood Soomro, Zubair Ahmed Memon
• Format: Article
• Language: English
• Published: IEEE 2018-01-01
• Series: IEEE Access
• Subjects: Buck-buck/boost converter; variable on-time control (VOTC); constant on-time control (COTC); critical conduction mode (CRM)
• Online Access: https://ieeexplore.ieee.org/document/8573577/
• ISSN: 2169-3536

When the on-time is constant during a line cycle, the input power factor (PF) of critical conduction mode buck-buck/boost power factor correction converter is low. A variable on-time control (VOTC) scheme is put forward in this paper to realize high PF. By utilizing the input and output voltage to modulate the on-time of buck and buck/boost switch, we can realize high-input PF with low-total harmonic distortion within the universal input voltage range. The operating principles and the comparative analysis of the converter with conventional constant on-time control (COTC) and VOTC are analyzed. The proposed control scheme achieves high PF and efficiency as compared with the COTC. A 100-W prototype was built up to verify the effectiveness of the proposed control strategy.