Research On A New Smith Predictive Compensation Network Control System

In the control system,the introduction of network communication,signal transmission and intelligent node module constitute the network control system,which makes the control range,wiring,cost improved.However,due to the nature of the network itself,the communication between several nodes has network delay.The appearance of network delay makes the control effect of the whole closed-loop networked control system worse,and may even lead to system instability.In view of the complex structure,many parameters and difficult tuning of networked control system,the parameter tuning problem of networked control system is transformed into parameter optimization problem,and an improved adaptive quantum genetic algorithm is proposed to optimize the parameters.For networked control system with random time delay,the fractional order system is insensitive to parameter changes and has large adjustment space to improve the Smith predictor’s requirement for accurate model of controlled object.A new Fractional Order PID network control algorithm based on Smith predictor compensation is proposed,and the improved adaptive quantum genetic algorithm is used to optimize the parameters.Aiming at the networked control system with long random time delay and no external interference,the generalized predictive control is improved,and combined with PID algorithm,a composite network predictor is proposed.A time delay compensator based on predictive output is used to compensate the feedforward time delay.Combined with the new Smith predictor,a composite network control strategy is formed to improve the stability and compensate the feedback time delay.Aiming at the networked control system with external disturbance and random time delay,the Smith predictor controller can transform with the internal model controller under certain conditions.Combined with the fractional order control,a two degree of freedom fractional order internal model network control algorithm is proposed to make up for the high precision requirement of the new Smith predictor and improve the robustness of the system.In MATLAB truetime2.0 toolbox combined with Simulink to build a real-time closed-loop network control system,the optimization algorithm and three control strategies are simulated.The simulation results show that under the optimization algorithm and control algorithm proposed in this paper,the control effect of networked control system is better,which verifies the superiority of this algorithm.