Stability margin analysis of DC-DC converter with fuzzy parametric uncertainty

This study presents a stability margin (SM) analysis of a pulse-width modulation (PWM) push-pull dc-dc converter that involves applying the zero exclusion theorem and Tsypkin-Polyak plot. The SM of linear affine dependency coefficients can not only determine whether a given system is robustly stable but also indicate the degree of an allowable disturbance under which the system is robustly stable. In addition, the problem of determining the SM of a PWM dc-dc converter with fuzzy parametric uncertainty is studied. Fuzzy numbers describing the system parameters are allowed to be characterized using arbitrary nonsymmetrical membership functions as well as the limitation that an operating point does not lie in the middle of admissible parameter intervals is excluded.