Parameter scheduled robust MIMO DC-DC converter control

Abstract

Abstract This project presents the design and evaluation of different controller strategies for voltage regulation of a resonant LLC DC-DC converter. The controllers evaluated include the classical proportional and integral controllers, as well as the more robust model-based control methods. To handle the nonlinear characteristics of the converter, the project also explored gain scheduled, and linear parameter-varying control methods using an affine state-space representation derived from existing converter models. Robustness was evaluated by simulating the disturbance rejection capabilities of the controllers. The results show that while the robust control methods provided increased robustness for a larger operating range, they also resulted in overly conservative controllers for certain operating conditions. The LPV controller managed to improve robustness throughout the whole operating range without affecting controller response times, emphasizing the importance of including nonlinearity in the control design for this type of converter.