Analysis And Design Of The Direct Drive Volume Control Of Rudder System

The ship rudder system is one of the important manipulative equipments. The ship's reliability and stability are influenced by its performance directly. Because the traditional hydraulic rudder system has many disadvantages such as low efficiency, great noise and vibration, the new high performance hydraulic rudder system is designed by direct drive volume control(DDVC) in this paper. And the control strategy of DDVC rudder system is researched. The research plays an important promoting role in the development of ship rudder system and application of the DDVC system.In this paper, the traditional electro-hydraulic rudder system and the direct drive volume control rudder system are compared on the basis of looking up many references. The research contents are determined according to the status of the direct drive volume control and the genetic algorithm in the ship motion control. According to the composing and working principle of DDVC rudder system, its velocity control system is selected and modeled. The transfer function models of actuating unit and DDVC rudder system are built by the linearization method. Because the rudder hydrodynamic is not only the power index, but also the force disturbance of the rudder system, the rudder hydrodynamic characteristics are analyzed and modeled. The hydrodynamic curve is determined according to some rudder parameters. In order to make accurate dynamic characteristics simulation and analysis of DDVC rudder system, the nonlinear simulation model of DDVC rudder system is set up with Amesim software based on the power bond graph. The nonlinear model bases the dynamic simulation of DDVC rudder system. The PID controllers of synchronous motor velocity control system and DDVC rudder system are separately designed substituting system simulation parameters. And the respective dynamic characteristics simulations are carried out. The DDVC rudder system is analyzed and summarized according to simulation curves. To enhance the overall performance of DDVC rudder system, the traditional PID controller is optimized with the genetic algorithm aiming at its disadvantages such as low accuracy, bad stability and so on. It can be found that the optimized system can better meet the performance index demand of hydraulic rudder system through contrasting the simulation curves of PID controller and optimized system. The optimized system is improved no matter its rapidity or tracking accuracy.