Fuzzy Control of Fin Stabilizer at Zero Speed Based on Improved Genetic Algorithm

Frequency spectrum of ocean wave is analyzed to enhance the efficiency of fin stabilizer when the intensity of wave is changing. Random optimal control system with quadratic performance index is designed based on the extended state functions. Performance index weight matrices are optimized with genetic algorithm to find the best matching point between energy consumption and effect of roll reduction. Basic genetic algorithm is improved by analyzing characteristic of the system. Random optimal control in different sea levels is realized by introducing fuzzy control rules for weight matrices. Simulation results indicate that roll movement of ship can be reduced with least energy if weight matrices are fixed according to external disturbances