Modeling And Controlling Of Ultra-deep Drilling Winch-type Heave Compensation System Based On DDVC

The detection and exploitation of marine resource need advanced ultra-deep water and ultra-deep drilling technology. The ultra-deep drilling heave compensation system is one of important equipment in float drilling. The design of winch-type heave compensation system is based on direct drive volume control (DDVC) and hydraulic energy recovery technology about transformer. It compensates heave displacement of the drill string by controlling the winch.The part of DDVC in the system has some advantages. Such as high efficiency, wide range of speed regulation, control flexibility. However, the DDVC system belongs to the volume control, so the system has slow speed response and poor control characteristic. So the research of DDVC hydraulic system to improve the dynamic characteristics is one of the important subjects in this paper.The motion of platform is a disturbance in winch-type heave compensation system, the purpose of compensation is that ensuring drill pressure is constant. The regular feedback control belongs to a control method after the error appearing, the accuracy is not high and the speed response is slow. It can’t make sure the control mechanism of compensation operation has same movement with floating platform heave movement. Therefore, the problem of improving system compensation accuracy is another key problem in this paper.In this paper, the main research work is as follows:1. The model of directly drive volume control hydraulic motor system in winch-type heave compensation system is established. The AMESim simulation model of direct-drive pump-control-motor system is built. Then, having a simulation analysis of mathematical model and AMESim simulation model. To explore the response characteristics and stability of direct-drive pump-control-motor system.2. In order to improve the dynamic characteristics in winch-type heave compensation system, the scheme of variable speed-variable displacement pump-control-motor system and multiple sets and different power motors and different displacement pumps collocation direct-drive pump-control-motor system is proposed. And it has a simulation analysis in the MATLAB/Simulink and AMESim. It verifies that the proposed scheme is reasonable.3. Improving the total control scheme of winch-type heave compensation system, the nonlinear disturbance compensation controller based on platform movement speed prediction is proposed. It compensates the displacement of the hook. It improves the compensation precision of the system.4. The direct-drive winch-type heave compensation system test bench is designed. The structure design and AMESim modeling simulation of test bench is done. And an analysis of the test bench compensation characteristic and response characteristic is done. The speed response of servo motor experiment is done. It verifies the model of servo motor is correct. An experimental analysis with a predictive compensation controller based on the ocean heave motion platform is done. It verifies the proposed prediction scheme is reasonable.