Design of Robust Digital PID Controller for H-Bridge Soft-Switching Boost Converter

In this paper, a robust digital proportional-integral-derivative (PID) controller is proposed for the H-bridge soft-switching boost converter (HSBC). This digital PID controller is designed to ensure load voltage regulation as well as to give robust performance with step loads and source rejection. The mathematical models of the H-bridge boost converter are formulated, using the system identification tool, and then used in digital PID design. Here, this compensator is designed in the direct digital domain according to a pole placement approach that uses sensitivity function shaping in order to ensure closed-loop converter system stability as well as robust performance against converter parameter uncertainties. To confirm this, design simulations have been carried out on a 60-W 24-42-V HSBC. The experimental results are provided to validate the robust controller design concept.