控制理论基础-自控a_ch1

1,MODERN CONTROL SYSTEMS,许向阳,教1411School of AutomationBeijing Institute of Technology,自动控制理论A,2,References,1 Richard C. Dorf , Robert H. Bishop. Modern Control Systems (Eleventh Edition) M. 电子工业出版社，20092 Katsuhiko Ogata. Modern Control Engineering (4th Edition) M. Prentice-Hall International, Inc. 20023 胡寿松，自动控制原理（第四版），科学出版社，2001 4 梅晓榕，自动控制原理，科学出版社，20025 吴麒. 自动控制原理. 清华大学出版社，1996,3,Contents,Chapter 1. Introduction to Control Systems (1 hour) 概述Chapter 2 Mathematical Models of Systems (5 hours) 数学模型Chapter 3 Feedback Control System Characteristic （8 hours）反馈控制系统特性,4,Contents,Chapter4 The Stability of Linear Feedback System (4 hours) 线性系统稳定性（劳斯判据）Chapter5 The Root Locus Method (12 hours) 根轨迹法Chapter6 Frequency Response Methods (6 hours) 频率特性法Chapter7 Stability in the Frequency Domain (6 hours) 频率域稳态分析,5,Contents,Chapter8 The Design of Feedback Control Systems (6 hours) 系统的校正Chapter9 State Variable Models (8 hours) 状态变量模型Chapter10 The Design of State Variable Feedback Systems (8 hours)状态变量反馈系统设计,6,Ch1. Introduction to Control Systems,1.1 Introduction 1.2 History of Automatic Control 1.3 Example of Control System 1.4 Engineering Design 1.5 Control System Design 1.6 Design Example,7,1.1 Introduction,1. Control System A control system is an interconnection of components forming a system configuration that will provide a desired system response. 1.1 Process to be controlled 1.2 Open-loop control system (without feedback),Process,input,output,Actuating device,Process,Desired output response Output,Controller,8,2. Open-loop Control System,An open-loop control system utilizes an actuating device to control the process directly without using feedback .,Eg: automatic toast,Input: electricityOutput: thermal,所以，如果输入量和输出量的关系已知，并且不存在内部和外部扰动时，采用开环控制是适宜的。当系统存在着无法预料的扰动和（或）系统中元件参数可能有无法预料的变化时，闭环系统就显得更为优越。,缺点：无法控制烤得程度,9,3. Closed-loop Control System,Desired output response,Actuator,Controller,Process,Sensor,-,A closed-loop control system uses a measurement of the output and feedback of this signal to compare it with the desired output ( reference or command ),Error,Output,Feedback,Measurement output,10,1.2 History of Automatic Control,11,Two example of the use of feedback,Famous dreams (Original idea),The design of improved signal amplifier. HAROLDBLACK, was assigned the task of linearizing, stabilizing, and improving the amplifiers that were used in tandem(先后) to carry conversation over distances several thousand miles.2. Creation of a gun director (火炮射击指挥仪)David B. Parkinson,How to Use the feedback,Inovation,12,The Control of an industrial process by automatic rather than manual means is often called automation The Use of Control System: (1) Increased production (提高生产率) (2) Improved performance (改善性能),Control Engineering Practice,13,In 1925, some 588,000 people were needed to mine 520 million tons coal.Now, 72,000 workers produce 482 million tons.,But, there still have a lot of plants to be changed and improved, especially in China. video1,14,1.3 Examples of Control System,1. Driving Control,Driver,Steering Mechanism,Automobile,Measurement,驾驶员利用实际行驶方向与预期方向之间的差异来调整方向盘。,DesiredCourseOf travel,ActualCourseOf travel,-,15,Automobile Steering control system,16,2. A manual control system for regulating the level of fluid in a tank by adjusting the output valve 3. A three axis control system,17,4. Unmanned Helicopter,KOAX X-240 (Switzerland),18,5. A feedback control system model of the national income.,Government,Consumers,DesiredNationalincome,Nationalincome,Taxcollection,Business production,Measurement,-,-,19,1.4 Engineering Design,Design is the process of conceiving(构思) or inventing(发明) the forms, parts, and details of a system to achieve a specified purpose.Specifications, complexity, trade-off (平衡), design gaps (差距), risk (风险), synthesis (综合), optimize (优化).,20,1.5 Control System Design,Establish the control goals,Identify the variables to be controlled,Write the specifications,Establish the system configuration,Obtain a model of the process, the actuator, and the sensor,Describe a controller and select key parameters to be adjusted,Optimize the parameters and analyze the performance,The control systemdesign process If the performance does not meet specifications, If the performance meets,then iterate the configuration and the actuator. then finalize the design.,21, Establishment of goals, variables to be controlled, and specifications. System definition and modeling. Control system design, simulation, and analysis.,22,dcamplifier,Control device,Amplifier,Actuator,Dc motor,process,Turntable,Desiredspeed,Actualspeed,1.6 Design Example,Turntable Speed Control,(a) open-loop control of the speed of turntable,23,dcamplifier,Control device,Amplifier,Actuator,dc motor,process,Turntable,Desiredspeed,Actualspeed,_,SensorTachometer,b. Closed-loop control of the speed of turntable,24,Consideration：,（1）Whats the function of Tachometer? 转速计起的作用是什么？（2）whats the advantage with closed-loop feed back control compare with open-loop control 负反馈闭环控制比开环控制的优越性在哪？控制装置：Control device输入变量：input variable输出变量：output variable被测变量：measured variable控制对象：process传感器：sensor,开环控制 open-loop control 闭环控制 closed-loop control反馈控制 feedback co