Design And Experimental Research Of Hook Block Assembly Heave Compensation Experimental Table Control System With Composite Cylinder

Deep-sea oil and gas resource development mainly use semi-submersible drilling platforms, drilling rigs and other equipment. Due to the wave heave motion, semi-submersible drilling platform heaves up and down, so do the drill string. These will result in downhole drilling pressure fluctuations, even get the bit away from the bottom. It seriously reduces the drilling efficient and is more likely to cause an accident. Therefore, you must configure these drilling devices for heave compensation, which is used to compensate heave motion of the drill string.Control system of the composite cylinder heave compensation experimental table uses upper and lower control system structure. NI acquisition card controls the analog hull assembly, and keeps it simulate heave motion of hull. Lower machine PLC controls analog hook assembly, and compensates the hook heave motion, as well as requests the host computer. Upper machine monitors the system and sets parameters.In one hand, we build the mathematical models of composite cylinder heave compensation system. In another hand, with experiments and analysis in different types of power supply, control strategy and control a lgorithm, we will explore and find a better control system as well as provide a reference for the control system designed.First of all, three kinds of heave compensation system, which include passive, active and semi-active one, are modeled mathematically and simulated in AMESim. Meanwhile, simulation experiments are performed. By comparing the experimental results with the simulation results and it is found that semi-active heave compensation system combines the advantages of passive and active heave compensation system, which not only reduce energy consumption, but also ensure adequate control accuracy.Moreover, based on semi-active heave compensation system, we apply three types of control strategy, including valve control, pump control and pump control plus valve control, to bulid mathematical and AMESim model. At the same time, simulation experiments are performed, and we compare the experimental result with simulation result. With these, it is found that the pump control plus valve control system s trategy’s overflow loss is more less and control accuracy is good enough to meet the requirements of deep-sea drilling.Last but not the least, the control algor ithm of heave compensation system, in experiment above, is PID control algorithm, and the result meets the requirements of deep-sea drilling. Though it is easy to be disturbed, causing the system fluctuates frequently. Therefore, this paper gives an example of fuzzy-PID algor ithm for semi-active heave compensation system. With simulation and experimental study, the results show that the fuzzy PID algorithm overcome the effects of disturbance well, but also ensure the control accuracy.