Robust H-infinity control of neutral system for sampled-data dynamic positioning ships

摘要

This study focuses on the robust H-infinity sampled-data control problem of neutral system for dynamic positioning (DP) ships. Using the input delay approach and a state-derivative control law, the ship DP system is turned into a neutral system with time-varying delays. By incorporating the delay-decomposition technique, Wirtinger-based integral inequality and an augmented Lyapunov-Krasovskii functional, less conservative result is derived for the resulting system. Sufficient conditions are established to determine the system's asymptotical stability and achieve H-infinity performance using Lyapunov stability theorems. Then the H-infinity sampled-data controller is obtained by analyzing the stabilization conditions. Finally, simulation result is shown that the proposed method is effective.