Nonlinear and linear robust control of switching power converters

Switching power converters are nonlinear and time variant systems. The classical controller design for a switching power converter based on the linear model is derived by one of the conventional modelling methods. However the parameter and load variations and input unregulated voltage are not taken into consideration simultaneously in a controller design. In this paper, we use “input-output feedback linearization” technique for nonlinear control issue, and “Kharitonov, H∞ and μ-synthesis” techniques for robust control in design of nonlinear and linear robust controllers to access both satisfactory stability and satisfactory performance, even in case of uncertainties and disturbances, for typical fifth-order DC-DC switching power converter. The stability and performance of the converter and the effectiveness of the proposed controllers are demonstrated by some simulated results. Making use of simulation results, various comparisons between these controllers and a variety of other controllers are then made, exhibiting the high efficiency of these methods compared to conventional methods