Research On Manipulation And Control Of Retractable Fin Stabilizer

While ship is at sea, due to high waves, wind and other factors, inevitably produces various sway dramatic sway of the seaworthiness of the ship, the vessel's safe navigation equipment on board, cargo and crew have had a negative impact. For this reason, people have been seeking reduced sway of the ship, and device the development of many ships sway control. Fin Stabilizer is one of them.Fin Stabilizer is divided into non-retractable fin stabilizer and retractable fin stabilizer. This paper studies the manipulation and control of retractable fin stabilizer.Almost all the systems of fin stabilizers are posed by analog circuit, whose defects are clear. Its control precision, reliability and adaptability are not good enough. As the electronic technology develops so fast, the fin stabilizer also needs to be improved. So the alteration and improvement of servo system is necessary. Fin stabilizer system is a digital control system, which uses the computer systems to connect the control room, cab operational sites through the use of the networks. The control box of the plane has good self-diagnosis function to automatically display the state of fault, and alarm the staff. Besides, it also can send the work state and the fault information to the ship alarm system through the network. This paper draws a new circuit schematic of retractable fin stabilizer based on the original NJ-retractable fin stabilizer. Which uses independent control system to control the retractable fin stabilizer and the rotatable fin stabilizer, but they have the same set of hydraulic system. When the faule appears, contingency fault system is available, and the alarm will be given. Using the PLC control and drawing the ladder diagram. The common control law of retractable fin stabilizer is mainly of PID control, which is simple,effective and applicable. But the most obvious defect is that the PID parameters can not be adjusted, the controller parameters can not be changed correspondingly while the working condition is changed, which will result to the decrease of control effect. Therefore, PID controller by using cerebella model articulation control method which being adopted in fin stabilizer control is used in this thesis. Namely, when the working condition is changed, the PID controller by using cerebella model articulation controller parameter can be adjusted automatically on line according to some certain law in order to keep optimal control effect. The simulation using Matlab. Comparisoning compound control with the individual PID control. The result shows that the compound control haves better roll effect.