Research On High Precision Tracking Control Algorithm Of Servo System Based On Sea-based Platform

The ship servo system is difficult to track the moving target with high precision,when the measure ship is subjected to waves,tidal currents and other complex disturbance.At the same time,the measurement precision of servo system is also related to error and the inertial force caused by measurement ship swing and displacement.According to the performance index,the traditional servo system control method hardly meet the requirements.Therefore,it is necessary to propose a better control strategy,which can improve the tracking performance of the servo system.The simulation model of ship servo system is based on the data provided by the joint simulation laboratory in the paper.Based on the theory of the active disturbance rejection control and the fractional order control,the combined control algorithm of improved active disturbance rejection control and fractional order control for sea based platform tracking system is proposed.The algorithm improves the dynamic performance of the servo system,and provides technical support for the high precision tracking control of the large aperture antenna system under the condition of the offshore platform.Firstly,this paper introduces the overall structure of the ship borne servo system.According to the performance requirements of the servo system,the actuator is selected and verified.Secondly,the mathematical model of the high speed DC motor is derived,and a three loop simulation model of the servo system is established,and the model is verified by the PID control algorithm.Then,the active disturbance rejection control(ADRC)is introduced into the ship servo control system to solve the disadvantages of the traditional servo control algorithm.The structure and principle of ADRC are analyzed,and the extended state observer(ESO/LESO)is used as the transient process of ADRC.An improved linear active disturbance rejection controller(LADRC)is designed to improve the control performance of the system.Finally,based on the analysis of the limitations of LADRC,a new control algorithm(LADRC_FOPD)is proposed.The position servo loop(LADRC_FOPD)controller is designed,and the simulation results show that the combined control algorithm has better control performance,which provides a reference for further digital engineering realization.