Research On Sampled-Data Control For PMSM Servo System

In this paper,we focus on the sampled-data control problem of permanent magnet synchronous(PMSM)servo system by applying sampled-data control theory and H?control theory based on computer control system.This paper is organized as follows.Chapter 1 is the introduction part,which mainly set forth the background and significance of this thesis through the next several respects:First,we make a brief overview on the development of PMSM and its control technology;Then we introduce the the application of modern control theory in PMSM servo system;At last,we introduce the research status of computer control technology.Finally,the research contents of this paper are given.In Chapter 2,the operating principle and structure of PMSM is introduced simply,and the mathematical model of PMSM in different coordinate systems is also given.In Chapter 3,a method of designing H?controller for PMSM servo system is proposed based on i_d=0 control scheme.The Linear Matrix Inequalities(LMIs)condition of the existence of controller is given by applying Lyapunov stability theorem and LMI-method.In Chapter 4,considering the influence of quantization errors generated from the data transmission in sampled-data control system,a sampled-data controller for PMSM servo system with quantization errors is proposed based on the results of Chapter 3.In Chapter 5,by not applying the i_d=0 control scheme,the output tracking problem of PMSM servo system is studied based on the PMSM nonlinear system model.Since the system nonlinear parts satisfy the linear growth condition,a condition of the existence of controller is given by applying Lyapunov stability theorem and LMI-method.In Chapter 6,considering the situation that the system states are ummeasurable or difficult to measure when PMSM is applied in industry,a mthod of sampled-data roboust observer is proposed.The superiority of this method is that it can be extended to a more general Lipschitz nonlinear system,and there always exsit a sampling period to ensure the convergency of error estimation system.The optimal sampling period can be obtained by solving a LMI optimaziton problem.In Chapter 7,we summarize the whole contents of this thesis and point out the innovation of this thesis,then a further work shoud be done is proposed.