View
223
Download
2
Category
Preview:
Citation preview
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 1
AUTOMATIC CONTROL AND SYSTEM THEORY
Claudio Melchiorri
Dipartimento di Ingegneria dell’Energia Elettrica e dell’Informazione (DEI) Università di Bologna
Email: claudio.melchiorri@unibo.it
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 2
Automatic Control and System Theory
Monday Tuesday Wednesday Thursday Friday
09-10 5.5 L 5.2 L
10-11 5.5 L 5.2 L
11-12 5.5 E 5.2 E
14-15 1.4 L
15-16 1.4 L
16-17 1.4 E
Validity: 23/09/13 – 20/12/13
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 3
Automatic Control and System Theory
Validity: 23/09/13 – 20/12/13
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 4
Automatic Control and System Theory
The course deals primarily with the design of advanced control systems. Main topics: • Analysis of SISO / MIMO dynamic systems expressed in state-space • Structural (geometrical) properties of dynamic systems • Control synthesis for dynamic systems expressed in state space • Optimal Control • Non linear systems
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 5
Automatic Control and System Theory
Practical activities: • Matlab/Simulink • RTAI-Linux Exam: • Report on the practical part • Oral discussion Pre-requisites: • Basic courses on automatic control (continuous- & discrete-time domains) • Basic knowledge of geometry, mathematics, physics, electronics
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 6
Automatic Control and System Theory
Suggested books:
• Notes available @ http://www-lar.deis.unibo.it/people/cmelchiorri/
• G. Marro, Controlled and Conditioned Invariants in Linear System Theory • R. Carloni, C. Melchiorri, G. Palli, Esercizi di controlli automatici e teoria dei
sistemi, Esculapio Ed. Bologna, 2008.
• G. Strang, Linear Algebra and its Applications, Books and Matlab Toolbox of Prof. Marro available at: http://www3.deis.unibo.it/Staff/FullProf/GiovanniMarro/gm_books.htm
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 7
Automatic Control and System Theory
The course is composed by two modules Prof. Claudio Melchiorri:
• http://www-lar.deis.unibo.it/~cmelchiorri/
• Mail: claudio.melchiorri@unibo.it Dr. Gianluca Palli:
• http://www-lar.deis.unibo.it/~gpalli/
• Mail: gianluca.palli@unibo.it
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 8
Automatic Control and System Theory
Contents 1. The state space. Basic concepts and definitions; Examples of dynamic systems
expressed in SS; Numerical solution of differential equations; Control and Observation; Main problems of System Theory and Automatic Control.
2. Linear Systems. Linear non stationary and stationary continuous-time systems; Extension to discrete-time systems; Sampled systems in state space.
3. Properties of linear stationary systems. Controllability and Observability; Equivalent systems and Realizations; Canonical realizations; SS vs Transfer matrices; Physical meaning of zeros in the SS
4. State feedback. Eigenvalues placement by state feedback; State observers; Eigenvalues placement by output feedback.
5. Stability analysis. Lyapunov’s First (indirect) Method; Lyapunov’s Direct Method; Definite Positive functions and Lyapunov functions; Limit cycles; Stability for time-varying linear systems.
6. Optimal control. Sylvester and Lyapunov matrix equation. Definitions of norms for signals and systems; Optimal feedback control; Infinite horizon optimal regulation and tracking; Stability margins; Regulation with frequency specifications; Integral control; Finite horizon optimal control.
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 9
Automatic Control and System Theory
GOAL: control of complex dynamic systems Control:
Action on the system (machine, plant, process, …) to modify (improve) its behavior according to desired requirements
Necessity of:
• Devices for measurement and actuation (sensors, motors, …) • Elaboration system (DSP, PLC, …) “real-time” with a proper computing
power • Control laws to “decide” the proper actions to be applied to the system
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 10
Control … everywhere!
• Engineering applications • Chemical plants, machines and mechanical plants; Robotics;
Aeronautics; Space; … • Production plants & processes; Power generation and distribution; • Traffic control and management • Electronics, Electro-mechanics, Telecommunication, Mechatronic
devices • Transportation systems (trains, automobiles, …), Domotics, …...
• Other sectors • Economy and Finance • Social and Political systems • Environment and Ecology • Medicine and Biology • …
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 11
Control … everywhere!
• Energy generation and distribution
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 12
Control … everywhere!
• Process control
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 13
Control … everywhere!
• Manufacturing industry
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 14
Control … everywhere!
• Vehicle control
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 15
Control … everywhere!
• Consumer Electronics
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 16
Control … everywhere!
• Medical applications
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 17
Control … everywhere!
• Robotics
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 18
Control … everywhere!
• Science
Adaptive optics Atomic Microscope
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 19
Control … everywhere!
• Biology “Feedback is a central feature of life. The process of feedback governs how we grow, respond to stress and challenge, and regulate factors such as body temperature, blood pressure and cholesterol level. The mechanisms operate at every level, from the interaction of proteins in cells to the interaction of organisms in complex ecologies.” M.B. Hoagland, B. Dodson,
“The Way Life Works”, Times Book, 1995
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 20
A VERY short control history
• The origins • Mankind has always attempted to improve the behaviour of
(dynamic) systems by means of control • Only after the mid of the XIX century a structured (scientific)
approach has been followed
tem
po
Water Clock Ktesibios 300 B.C.
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 21
A VERY short control history
• Famous example: J.Watt and the automatic control of the speed of a steam motor (1798 ca)
Device for the automatic control of the speed
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 22
A VERY short control history
The origin of “Automatic control”
• In the second part of the XIX century, J.C. Maxwell and I.A. Vyshnegradskii independently developed the first methodological approaches to control (control theory) based on models described by differential equations
• During the first half of the XX century, Control Theory has been developed
both in the western countries and in the ex-URSS, based on • Engineering motivations in the West • Mathematical interests in the East
• The electronic amplifier with negative feedback (Black, 1927) was an important engineering achievement in Control Theory
• Theoretical developments on stability analysis by • Nyquist (1932) • Bode (1940)
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 23
A VERY short control history
Automatic Control become an engineering discipline in the 40’s Reasons:
• Second World War • Plane autopilots, cannon pointing systems, radar, …
• Development of electronic computers (beginning of the 50’s) • They allowed the implementation of complex theoretical results
• Space race (60’s and 70’s) • Possible because of the availability of “sophisticated” control systems
• Development of microprocessors (second part of the 70’s) and of DSPs (second part of the 80’s)
• Wide use of automation “concepts” in industries • Application of control devices in a multitude of systems also in non-
industrial contests
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 24
Bode Diagram
Frequency
Phas
e
Mag
nitu
de
-40 -30 -20 -10 0
10
10 0 10 1 10 2 -180 -135 -90 -45 0
A VERY short control history
• “Frequency” control techniques (based on Laplace Transform, Bode Diagrams, etc.) had a large diffusion during and immediately after the 2nd World War.
• These techniques are suitable for SISO linear time-invariant systems (“classical” control theory).
Re
Im
-
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 25
A VERY short control history
• On the other hand, e.g. with nonlinear or MIMO systems, these techniques show important limitations, and their applicability is greatly limited
• Starting in the late 50’s – beginning of the 60’s, different techniques have been developed for analysis and control design of MIMO systems (Sputnik - 1957).
• ”Modern” control theory
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 26
Current situation and perspectives
Sophisticated control systems are normally used in civil, industrial, miitary devices (hidden technology)
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 27
Current situation and perspectives
• Applications in engineering (non industrial) fields • Automobiles
• “modern” cars could not work without many control loops • autobrake, ABS, asset control, injection control, …..
• Consumer electronics • Photo/Video-cameras, cell phones, PC, … • Washing machines, fridges, cooling/heating,
• Domotics • Remote control of domestic apparatus • …
• Energy • Wind/Solar generation, …
AC&ST
C. Melchiorri (DEI) Automatic Control & System Theory 28
Current situation and perspectives
Other areas of interest:
• Biomedical devices • Biological systems • Environment • Socio-Economic systems • Financial markets • Management • …
Recommended