Research On The Control Strategy Of Electric-Driven Three-Axis Stabilized And Tracking Platform

This paper mainly from the naval forces of the shipboard terminal guidance tracking pilot project.Terminal guidance tracking device on the warship is an important factor affecting the warship combat. It can track the targets steadily and keep the stability of the geographical level guidance equipment. This project is to analyze the warship stabilized and tracking platform operating mode and study how it works, based on stabilized and tracking system stability, speed and precision requirements, as well as research to improve the system auto-tracking performance control strategy.Upon request of the subject, we must analyze stable platform for tracking mode, tracking works stable research platform, as well as to determine the driving scheme of the system, to determine the key parameters of the system.According to the control theory, a mathematical model of a single-channel motor servo position control system, in order to get the motor armature voltage input, the angular displacement of the motor output transfer function model. To improve the system performance requirements, according to the engineering design methods, design from the inside out for the current loop, speed loop, three closed-loop position control system position loop, according to the typical configuration of the system requirements for typeⅠcurrent regulator(ACR), speed controller(ASR) and a position regulator(APR) parameters on the basis of this analysis the system without outside interference stability, accuracy and rapidity.Based on a stable platform for tracking actual work situation, the introduction of the main interference position control system, on the one hand, to change the attitude of the platform led to the moment of inertia of the control object to change, so that the transfer function of structural changes; on the other hand the existence of a stable platform to track work friction disturbance, due to the low speed of the platform is introduced Stribeck friction model, and make the original linear system to a nonlinear system. Simulink simulation model established in the classical PID control, complete system step response and sinusoidal tracking, results show that the classical PID control in nonlinear systems, there is no such system, steady-state and dynamic performance to achieve a good result.For the classic PID control, nonlinear systems in response to the output accuracy and rapidity of this issue did not meet the requirements, the introduction of variable structure controller, the controlling system due to the elimination of structural change systems, and so the impact is not continuous. This paper based index reaching law sliding mode controller is designed to give the controller the angular displacement error, angular velocity, acceleration, given signal of the first-order and second-order differential, and built Simulink models for system unit step response and sine tracking simulation, the simulation results and contrasting classic PID control showed: sliding mode controller has better rapidity to meet dynamic requirements and reduce steady-state error, and can better resist outside interference, suppression structural changes affecting the system parameters of the system brings to achieve good control effect.Finally, with the platform on the warship’s tracking step, self-stabilizing system, position tracking experiment, verify the location of the control system mathematical model is reasonable. Compared the performance of the classic PID controller with variable structure controller, and the experiments show that sliding variable structure controller in the platform step response, auto-orientation and tracking controlling, the indicators system requirements are met, the controlling performance is better than PID controller.