The Design And Test Research On The Load Simulator Of The Ship Steering Gears

With the improvement of China's modern naval power and the rapid development of marine industry,it is of great strategic significance to develop the steering gear device with excellent performance.The steering gear device is an actuator used to change the navigational direction of the ship.During the actual navigation,the steering gear device is faced with complex and variable hydrodynamic loads which require better operational performance.In order to effectively improve the operational performance and service life of the steering gear device,shorten the development cycle,save the development cost and improve the development success rate,it is necessary to simulate the actual working load of the steering gear device to meet the demand of static and dynamic characteristic testing,and then to evaluate the overall performance of the steering gear device and improve the design scheme.This subject takes the load simulator of steering gears as the research object which can perform the static and dynamic loading test for the steering gear device under laboratory conditions,which reproduce the hydrodynamic load of the steering gear device during the actual navigation of the ship,and then test the performance indicators such as control precision and response speed of the steering gear device under different speed load conditions.The main research contents of the dissertation are presented as follows:(1)Combined with the domestic and international research status of the load simulator of steering gears,analyze the advantages and disadvantages of electrohydraulic,electric and pneumatic loading methods.In view of the wide range of hydrodynamic load of the ship's steering gear device,the electrohydraulic loading method is used to design the load simulator.Analyze the main technical difficulties of the load simulator and then determine the main research contents of this subject.(2)According to the performance test requirements of the steering gear device,identify the design indicators and functional requirements.Based on the control principle of the proportional relief valve and electrohydraulic servo valve to design the hydraulic system,and then select and calculate the main components.(3)Establish the mathematical model of the system to solve the mathematical expression of the displacement of the piston rod of the steering gear cylinder and the axial output force of the loading cylinder.Use the AMESim software to establish the simulation model of the system under the uncoupled state and coupled state,and analyze the closed-loop control characteristics of the load simulator based on PID control algorithm.The simulation results show that the steering gear system has better position closed-loop control characteristics,and the loading system is interfered with surplus force caused by the steering gear system during the startup moment and the commutation process.Analyze the generating principle and characteristics of the system surplus force.(4)Set up the test bench for the load simulator,including designing the three-dimensional model and constructing the object of the hydraulic system,designing the scheme and building the object of the electrical system,and using the Lab VIEW to write the control program and human-computer interaction interface of the system based on the CompactRIO embedded development system to realize the control function of the load simulator of steering gears.(5)According to the generating principle of the system surplus force,the subject proposes a fuzzy adaptive PID force tracking closed-loop control algorithm based on speed feedforward compensation to carry out the static and dynamic loading test for the steering gear device on the test bench.The test results show that the force control algorithm can effectively suppress the influence of system surplus force on the loading performance of the system.The static loading accuracy of the system is ±2%F.S,and the dynamic loading accuracy is ±4%F.S which is under the condition of high pressure oil source provided by the motor pump set or accumulator station.In summary,the static and dynamic characteristics of the load simulator can meet the performance test requirements of the steering gear device.