Research On Dynamic Characteristics Of Valve-Controlled Flange-type Rotary Vane Steering Gear

Steering gear is one of the important equipment to ensure the safety of the ship in the sea,and the good and bad of its handling performance directly affect the stability of the ship in complex marine environment. Steering structure of rudder has many forms, including flange-type rotary vane steering gear to the advantage of the structure,with its small size,anti-attack and good pressure performance, low noise and many other advantages, in recent years having attracted more and more attention . Flange-type rotary vane steering gear with having fast dynamic response and high precision control of the electro-hydraulic servo valve is composed of valve controlled flange-type rotary vane steering gear system has important research value for small ships.In practical sailing,the process of controlling the steering gear will be affected by hydrodynamic force, friction, saturation and leakage, which seriously affect the dynamic characteristics of the actuator. The main content of this thesis is to improve the structure and design the controller to reduce the influence of these factors on the dynamic characteristics of the actuator system. The main works of this paper are as follows:Firstly, Analysis on the research results of the rotary vane steering gear at domestic and foreign major companies and shipyard,and the research results of the dynamic characteristics of the steering gear. introduced the workflow and their respective characteristics of the valve-controlled hydraulic actuator and pump-controlled hydraulic steering gear briefly,summed up the advantages and disadvantages of different steering mechanism of hydraulic steering gear.Secondly, the internal structure of flange-type rotary vane steering gear is analyzed in detail, in order to reduce leakage, an new-type sealing structure is designed. On the basis of working principle of the investigative valve-controlled flange-type rotary vane steering gear,Mainly for the electro-hydraulic servo valve, rotary vane cylinder as well as the hydrodynamic force to establish its mathematical model through theoretical analysis.Then, some important parameters of flange-type rotary vane steering gear are analyzed,used to obtain the important parameters of simulation research, and has carried on the analysis of the stability of the system. It focused on the impact of the system in the hydrodynamic interference, friction, saturation and leakage as well as considering the effect of these factors on the dynamic characteristics of the system.Finally, aiming at the problem of the dynamic characteristics of servo system under the influence of many factors, a fuzzy PID controller is designed, which is suitable for this system. The performance of the system is improved by simulation analysis and comparison, it is proved that the designed controller can reduce the impact of these factors on the system.