Research On The Control Method For Dynamic Positioning System Of Marine Multipurpose Ships

With the gradual development of the ship to the direction of the automation and intelligent, the intelligent degree of the ship positioning system is also growing, more and more ships are equipped with a Dynamic Positioning System, compared with the traditional mooring system, it is not limited to the depth of water, and it has good maneuvering performance, fast reaction speed and accurate positioning, setting intelligent design in one. Under the support of “Joint innovation funded project of Jiangsu Province”, “Jiangsu University High Tech ship collaborative innovation center / marine equipment research institute funded projects”, and “Project funded by the Jiangsu University of science and Engineering”, taking the marine multi-purpose ship as the research object, the control method of Dynamic Positioning System is discussed and studied, and this paper has definite engineering background and practical value. The main contributions are as follows:In order to research the ship Dynamic Positioning System more conveniently, the hydrodynamic mathematical model, environmental disturbance force mathematical model and the ship motion mathematical model are established. At the same time, using wavelet threshold de-noising to pre-process the output data of the ship measurement system, in order to obtain the accurate model parameters of the system, and applying it into the model parameter identification.In view of the complex and uncertain characteristics of the ship system model, the strong tracking filter is selected to overcome the filter divergence problem in the case of model mismatch. By linear simulation, the strong tracking filter is compared with the Kalman filter. Also, the extended Kalman filter and strong tracking filter are designed in the marine multi-purpose ship. The simulation results of the two cases are fully verified the superiority of the strong tracking filter in the case of model mismatch.Ship mathematical model can't fully match the ship's mathematical model, when the ship is affected by the external environment or ship's load changes and so on. In order to ensure that the ship can accurately locate and complete the operation of the sea, the generalized predictive control which has the superiority of adaptive control and predictive control is adopted, and the genetic particle swarm optimization algorithm is proposed, applied it into the rolling optimization of the generalized predictive control to improve the speed and precision of the optimization effectively. Designing a simulation experiment for the marine multi-purpose ship, ordinary generalized predictive controller and the improved generalized predictive controller respectively combined the strong tracking filter, designing a complete point positioning experiment, verifying the effectiveness of the generalized predictive control based on the genetic particle swarm optimization algorithm, and it has a certain reference value for the practical engineering application.