Abstract

This paper presents a generalized controller design to regulate the output voltage of second-order DC-DC converters feeding an unknown constant power load (CPL). Passivity-based control plus damping injection theory is employed to design a generalized action control to stabilize DC-DC converters. Furthermore, starting from the immersion and invariance (I&I) method, a generalized observer for second-order DC-DC converters is implemented to estimate the CPL value. By mixing the proposed controller with the I&I method, an adaptive generalized control approach is presented, which guarantees the locally asymptotic stability of the closed-loop for each converter. The main advantage of the nonlinear adaptive control design is its nonparametric dependence on the capacitance and inductance values, which makes it robust against parametric uncertainties. Phase portrait and sensitivity analyses are performed, and simulation and experimental results are examined to evaluate the performance of the proposed approach, which is also compared against feedback linearization and sliding mode control. Simulation and experimental results show the robustness and effectiveness of the adaptive proposed control approach.