Adaptive back stepping observer design for direct current link capacitor voltages of multi port high power converter

摘要

This paper presents an adaptive nonlinear observer design to investigate and fix precise estimation issues of dc link capacitor voltages in a powerful three-phase multi-level two ports converter. An Adaptive Back Stepping approach using the phase currents as observer inputs was applied to estimate the capacitor voltages in two ports multilevel cascaded H-Bridge converter. Capacitance of dc link capacitor was used as uncertain parameters to prove the robustness and sustainability of the proposed estimator against uncertainty. Evaluating the results represented possibility of reducing the number of sensors for fault detection purposes, precise tracking and exact estimation of unmeasurable variables. Nonlinear proposed control design based on the Lyapunov theory guarantees the stability and convergence of variables. Evaluation of the proposed solution results have been done in Matlab / Simulink.