Research On Enhanced Technologies Of Servo Parameters Self-tuning Based On Evolutionary Algorithm

High speed and high precision applications demand good dynamic performance and stability for servo drive system. Traditional PID controller remains most widely used in the control of servo drive system due to its advantages of simple structure, high efficiency and easy to implementation. Since the controller parameters influence the control performance, PID controller tuning method is developed and self-tuning software is designed to complete the automatic optimization and configuration of the PID controller. The main contents of this thesis are as follows.Considering of three-loop control structure of servo drive system, the time domain performance evaluation is studied. According to model-based and role-based self-tuning strategies, the enhanced self-tuning platform overall scheme is designed.Based on the evolutionary algorithm, an enhanced controller self-tuning method is addressed in detail. This method adopts particle swarm optimization to identify the accurate mathematical model of the system. In order to limit the input energy and high overshoot while keep the rapidity of the system simultaneously, an advanced comprehensive performance evaluation on the basis of integral absolute error is incorporated into the proposed method. Meanwhile, genetic algorithm is employed for the optimization of PID controller to determine the optimal control parameters.A controller self-tuning software is developed for servo drive system. The software possess multiple meaningful functions, such as parameters configuration, time domain performance testing and controller self-tuning etc. The overall framework of this software is elaborated, so does the key modules including self-tuning module, data acquisition module and time domain graphical interface module.Servo drive system platform is built. Functional test is conducted to show the feasibility and practicability of the developed self-tuning software. Moreover, step response and speed tracking test are performed to demonstrate the accuracy, stability and effectiveness of the proposed strategy. The results indicate that the controlled system maintains superior dynamic performance under the presented method.