| HCS for deep-sea mining device is one of the absolutely necessary instruments to secure the deep-sea mining production. For example, when mining the manganese nodule which is of very high mining value and dispersed on the 5000m depth ocean floor, in order to reduce the effect of the mining ship on the lifting pipe, it is necessary to install a HCS between the lifting pipe and the mining ship to reduce the axial stress and deformation of the lifting pipe and avoid its fatigue damage. In this thesis, HCS is studied by means of theory analysis, computer simulation and model test, among of which HHCS for lifting pipe is the main research object.Three kinds of HCS, LHCS, MHCS, HHCS, are put forward for different purpose, which use synthetically the technologies of electro-hydraulic proportional control, computer control and intelligent control and have compact structure, good reliability, and high compensation precision. The parameter of HHCS which uses the speed-type heave compensation strategy is designed, and the result of the parameter design shows that the designed HHCS meet the requirement of heavy load as well as small power consumption. For the model test, a multifunctional model test-bed is built which can build LHCMTS, MHCMTS, and HHCMTS based on the similarity principle. Any HCSMTS is composed of a HMSS, a HCMS and a load simulation system.In order to satisfy the demand of theory analysis and computer simulation, firstly, the mathematic models are established for the spool movement of a proportional direction valve, the actuating unit with a 4/3-way asymmetric proportional direction valve controlling an asymmetric cylinder and the actuating unit with a 3/3-way asymmetric valve controlling an asymmetric cylinder, and the transfer functions are obtained for HHCS, HMSS, LHCMS, MHCMS and HHCMS. And then, a new kind of simulation modeling method based on the power bond graph and the software simulink to build the simulation model of a hydraulic system's executing process. It is proved correct by comparing the simulation result of the HMSS with its experimental result, and it also can be used to build the dynamic/static performance simulation model of a hydraulic system. At last, using the established mathematic model and the presented simulation modeling method, the static performance simulation model of the HHCS is built, and the heave compensating simulation model is built for the HHCS, HHCMTS, MHCMTS and LHCMTS.The analysis and simulation of dynamic/static performance of the HHCS shows that it is a large inertial system, and that there are such adverse factors in HCS and its model test system as nonlinear, dead zone, time variable parameters(e.g. load, friction), big delay. Therefore, it is very important to design their controllers and choose theircontrol strategy. In order to improve the position tracing precision for simulating the heave motion of the HMSS, a feedforward controller is added into its controller except for a feedback. A multiplex controller, which is composed of a speed feedback controller, a displacement feedback controller and a disturbance compensation controller, is designed for the three kinds of HCS which use different heave compensation strategy. The feedfoward controller, low pass filter and two kinds of feedback controllers(PID controller and Fuzzy-PID controller) are designed. The disturbance compensation control has very significant effect on the compensation performance, especially to the large inertial HHCS. Three kinds of disturbance compensation controllers, linear, nonlinear and neural network, are designed to meet different requirement. Among of them, the disturbance compensation controller based on BP network has strong self-adapting ability.Computer on-line control of the HCS needs hardware and software. Taking HCMTS for example, the hardware component of the computer on-line control system for HCS is introduced. Through the brief introduction of the control software developed for the HCMTS, several main technical difficulties are found and solved. The c...
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