Research On The Method Of Dynamic Positioning Ship Fault Tolerant Control

In order to develop the marine resources safely,make use of the existing equipment effectively,and take into consideration the environmental protection,the high-tech equipment for the marine development emerges one after another.The dynamic positioning ship plays an important role in the development of the ocean,and the dynamic positioning technology is constantly updated,which has higher requirements on safety and reliability.Considering the complexity of the marine environment,the ship may encounter a variety of emergencies in the job,people require that even if there is a fault,the ship still has the ability to complete the task during the work.The fault reconstruction control algorithm can effectively improve the safety of ship or other marine equipment and the reliability of operation.Therefore,this research has certain theoretical value and engineering application value.In this paper,the faults of actuators and sensors are analyzed in detail.The paper research the fault reconstruction control algorithm based on the sliding mode and adaptive control algorithm adaptive control algorithm.The main contents of this paper are as follows:Firstly,according to the kinematics and dynamics characteristics of the ship,the ship motion is modeled,and the three degree of freedom mathematical model of the ship is obtained.According to the three degree of freedom mathematical model of the ship,the common motion model of the sensor and the actuator,the physical process of the ship is simulated by using the physical parameters of a ship.The second in this paper,the active fault tolerant control is used to design the sensor reconfiguration module aiming at the sensor failure.Using a new sliding mode surface to design the sensor reconfiguration module.The nonlinear link,modeling error and external disturbance are dealt with by the reconfiguration module.Finally,the stability is verified.Then aiming at the ship actuator fault,using sliding mode variable structure control method to design the fault tolerant control,and the use of adaptive control of nonlinear system is part of the link and the model error and uncertainty.The sliding mode variable structure using the integral sliding surface,inevitably produce discontinuities,the differential control link to amend it,makes the whole control curve is more smooth,and analyses the stability.Finally,the sensor and actuator module reconstruction module is applied to the design of the ship dynamic positioning.According to the fault model,fault tolerant control based on sliding mode sensor reconfiguration module and adaptive sliding mode actuator reconfiguration are designed.Sensor fault tolerant control module and actuator fault tolerant control module integrate together to reach the realize the system fault tolerant control.The simulation results show that the design is reasonable and effective.