Comparative Analysis of Three Nonlinear Controllers for Boost Converters and Switching Design

This paper regards the boost converter as a variable-structure nonlinear system from an automatic control viewpoint. Three main nonlinear controllers contain feedback linearizing controller, passivity-based controller and sliding mode controller based on well-known average PWM model are introduced and their designs and performances are compared. The comparative analysis shows that although all these ones could stabilize the system they have distinct features. Sliding mode controller provides the best robustness. Feedback linearizing controller has quicker response than the other two. The design of passivity-based controller is quiet complex but it has better ability against disturbance than that of feedback linearizing controller. On the basis of analysis and comparison and the superiority of dwell time, a mixed switching law is designed to achieve rapid response while maintaining a certain anti-perturbance ability and robustness. The choice of design parameters proves to be crucial to ensure robustness with respect to load resistance variations.