Research On Deep-sea Servo Valve-controlled Cylinder System

There are far more resources in the ocean than in the land. As China extend the exploration of the ocean and exploitation of deep-sea resources, more and more equipment will be applied to the deep-ocean. The hydraulic system has several unique advantages, which make it widely used in submarine equipment, to provide power. But at present, the application of submarine hydraulic system is still confined in shallow water. As for deep-sea areas, especially below2000meters, the application of submarine hydraulic system stays at experimental stage. The research refers to dynamic characteristics for the servo valve controlled cylinder system applied at deep-sea, with the purpose of obtaining how the characteristics of the hydraulic system change at deep-sea conditions.First, the paper gives a comprehensive introduction to the submarine hydraulic system, which key technologies also are demonstrated. To a certain extent, the pressure and volume compensation can be solved by pressure compensators in submarine hydraulic systems. However, the characteristics of the hydraulic oil can be changed by high-pressure compensation, and considering deep-sea conditions the variation of oil properties is studied further. Secondly, based on valve-controlled asymmetrical cylinder servo system in the manipulator, the important parts of the system are modeled and analyzed to obtain the mathematical models of hydraulic servo and the submarine valve-controlled cylinder system.Then, the simulation model of the servo valve is created by the simulation software, by which the simulation is carried out based on model parameters of the selected servo valve. Compared to the simulation results at different depths, the influence of the deep-sea conditions upon the servo valve can be confirmed. Finally, the system of submarine valve-controlled hydraulic is designed grounded on the single joint of the manipulator from an institute. Besides, simulation parameters at different depths are concluded. The simulation model of deep-sea valve-controlled is built to acquire the simulation results at different depths.Comparing different simulation curves, it is clear that how the characteristics of deep-sea valve-controlled cylinder changed affected by deep-sea conditions.