ADAPTIVE OBSERVER DESIGN FOR A MARINE PROPELLER

Recently, new control designs and performance monitoring schemes for electrically driven marine propellers have been developed. The new control designs have been shown to increase the thrust capability, reduce mechanical wear and tear, and limit power transients. To achieve optimum performance, these designs rely on knowledge of the friction in the propeller drive system. Since this information not necessarily is available, a nonlinear adaptive observer for estimating the propeller load torque and the coefficient of friction is developed. Experiments are provided to verify the observer performance.