This article presents voltage-mode control (VMC) and peak current-mode control (PCMC) implementations for a phase shifted full-bridge (PSFB) converter in a highly integrated microcontroller (MCU)-based system. Adaptive zero-voltage switching (ZVS) and various synchronous-rectification schemes are discussed. Details for generating complex gate-drive waveforms, required by such control schemes, and intelligent timing control, to optimize system performance under changing operating conditions, are also provided.
Experimental results obtained using two PSFB systems (600W and 360W) are presented. A constant high system-efficiency above 10% rated load, novel PCMC waveform generation, and simple system implementation are the highlights of this implementation.
Part 1 presents an introduction, operational highlights including voltage mode control (VMC), peak current-mode control (PCMC), zero-voltage switching (ZVS) or low-voltage switching (LVS), synchronous rectification, and output-voltage rectification with changing load. To read it, click here.
Part 2 presents detailed test results and a summary. It will be posted shortly.
About the author
Hrishikesh Nene is in C2000 Systems and Applications, for Texas Instruments Incorporated.