Feedforward Compensation for Phase-Shifted Full-Bridge DC–DC Converter Under Peak Current Mode Control
Baozhu Liu, Yu Tang, Leijiao Ge, Jincai Niu
Abstract
One of the basic requirements of a highperformance isolated full-bridge DC-DC converter as a controlled DC voltage source is to obtain a constant output voltage quickly and accurately during load changes. In order to achieve a fast dynamic response, this paper studies the feedforward control method based on the peak current mode control for the isolated full bridge converter, and proposes a peak current feedforward (PCFF) control scheme with phase shift control to improve the dynamic performance of the converter. Through modeling and analyzing the steady-state large-signal of the phase-shifted full-bridge converter (PSFB), a feedforward prediction method for the PSFB converter under peak current control is obtained. In addition, this paper built a PSFB converter experimental platform in scale, and test the steady-state and dynamic performance of the proposed control method on it. Based on peak current controller, the dynamic performances for PSFB converter under the double-loop control strategy, load current feedforward control strategy and the proposed control strategy are tested and compared. The experimental results verify the improvement effect of PCFF control on the dynamic performance of PSFB converter