1 / 20

CONTROL SYSTEM

CONTROL SYSTEM. AN INTRODUCTION. Contents. 1. An Motion Control System 2. Purpose of Closed-Loop Control 3. Servo and Regulation Systems 4. Controller 5. How to Identify System 6. Summary. 1. An Motion System.

taliaferro
Download Presentation

CONTROL SYSTEM

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CONTROL SYSTEM AN INTRODUCTION

  2. Contents • 1. An Motion Control System • 2. Purpose of Closed-Loop Control • 3. Servo and Regulation Systems • 4. Controller • 5. How to Identify System • 6. Summary

  3. 1. An Motion System

  4. Plant: Input-output relationship (transfer function) may vary uncertainties (including time-varying) and Disturbances Nominal Model G(s)=5/(s+1) Actual Model G(s)=5.9/(s+1.3) Sensor: output may be digital or analog. Its input: real “speed”, its output: “readable data” of speed Actuator: Its input: “readable data” of the voltage of the power source. Its output: voltage, with needed current

  5. Decision Making: Controller Analog Controller Digital Controller

  6. 2. Purposes • Open-loop: speed varies with the motor and load for a given drive voltage • Closed-loop: Compensates for the influence of the variations in the motor and the load (uncertainties and disturbances) on the speed.

  7. 3. Types of Systems • Servo Systems: the desired speed (set-point) changes fast. Major requirement: to follow the changing “set-point” at an acceptable speed and accuracy. • Regulation Systems: the desired speed does not changes very fast. It may be constant. Major concern: substantial uncertainties/disturbances and high accuracy.

  8. 4. Controller • What does a controller do? Decides how to respond to the observed difference between the measured speed and the desired speed set-point. • How should the controller respond? Primarily based on the model, which describes the relationship between the input (voltage) and the output(speed) Robust Control: also largely based on the uncertainties • An important Step in System Design: Find the model (system identification) • Design: compromise between the uncertainties /disturbance and the response speed.

  9. 5. How to Identify the System Analyze the input-output data pairs to fit the parameters in the used model (structure) How to analyze and how to generate the data pairs for analysis: System Identification

  10. SYSTEM IDENTIFICATION INTRODUCTION

  11. Contents • 1. System • 2. System Identification • 3. Importance • 4. Why Specific Techniques? • 5. Example • 6. Summary

  12. 1. System • System: an object in which variables of different kinds interact and produce observable signals • Control engineers’ views: • Process producing outputs from inputs • Outputs: • Inputs: manipulated to change the outputs • Disturbances:

  13. 2. System Identification • End products: empirical models of systems • Model: description of relationship among related variables • Theoretical Models: from first principles • Empirical models: • Observations of system variables • ==>Relationship among variables • ==> Models linking the variables

  14. 3. Importance • Control algorithms & system dynamics • First principles

  15. 4. Why Specific Techniques?

  16. 5. Example

  17. 6. Summary • Data Generation (Experiment Design) • Model Structure Determination • Parameters Estimation • Model Validation

More Related