1. Associate Professor, Department of Electrical Engineering Email: aziz.memon@iba-suk.edu.pk Dr. Abdul Aziz Memon Course: Advanced Control Systems (EE-501) ME-EE SUKKUR IBA UNIVERSITY MERIT – QUALITY – EXCELLENCE

2. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501)LMS-Contact-Channel-Zoom-WhatsApp LMS LMS http://elearning.iba-suk.edu.pk/login/index.php http://elearning.iba-suk.edu.pk/login/index.php Google form link-Contact Google form link-Contact https://forms.gle/zGHV1FdTfmQyB6ga8 https://forms.gle/zGHV1FdTfmQyB6ga8 https://forms.gle/zGHV1FdTfmQyB6ga8 https://tinyurl.com/sibauform https://tinyurl.com/sibauform WhatsApp WhatsApp 0333-3146-299 0333-3146-299 2

3. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501)Introduction A control system is a set of devices or mechanisms that manage, command, direct, or regulate the behavior of other devices or systems to achieve a desired output. A control system is a set of devices or mechanisms that manage, command, direct, or regulate the behavior of other devices or systems to achieve a desired output. First, we will cover: First, we will cover: Control Systems Terminology Control Systems Terminology And then And then Examples of Control Systems Examples of Control Systems 3

4. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501)Introduction Today (since many years) control systems are playing an important role in development of modern civilization (human society) and technology. (stone age to modern age) Today (since many years) control systems are playing an important role in development of modern civilization (human society) and technology. (stone age to modern age) Today, every system, has some type of control engineering involved in it. Today, every system, has some type of control engineering involved in it. Home heating system Home heating system Refrigerator Refrigerator Air conditioner Air conditioner Automobile Automobile 4

5. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501)Introduction Applications: In industries Applications: In industries Inventory control/management Inventory control/management Quality control Quality control Automatic assembly line Automatic assembly line Machine tool control Machine tool control (cutting, shaping, or assembling materials) (cutting, shaping, or assembling materials) 5

6. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501)Introduction Further applications Further applications Space technology (launch, navigate) Space technology (launch, navigate) Weapon systems (target) Weapon systems (target) Robotics Robotics Power plants Power plants 6

7. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501)Introduction There can be various control systems There can be various control systems Socio-economic systems (deals with education, health, employment, economy) Socio-economic systems (deals with education, health, employment, economy) Biological systems (body temperature/sugar level control) Biological systems (body temperature/sugar level control) Engineering systems (these systems follow certain laws of physics) Engineering systems (these systems follow certain laws of physics) Therefore, called physical systems Therefore, called physical systems We will be covering engineering systems only We will be covering engineering systems only 7

8. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Basic terminology System to be controlled is given different names System to be controlled is given different names Process (Chemical/petroleum/fuel production plant: control mixing, heating, composition, chemical reactions of substances, humidity, pressure, liquid level, air flow etc) Process (Chemical/petroleum/fuel production plant: control mixing, heating, composition, chemical reactions of substances, humidity, pressure, liquid level, air flow etc) Plant (Power generation plant: Controlling energy conversion) Plant (Power generation plant: Controlling energy conversion) Controlled system Controlled system Control techniques started with Process Control in around 1900 to 1940 Control techniques started with Process Control in around 1900 to 1940 8

9. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501)History Control techniques started with Process Control in around 1900 to 1940 Control techniques started with Process Control in around 1900 to 1940 During world war-II further control systems were needed to be developed During world war-II further control systems were needed to be developed Automatic airplane pilots (autopilot) Automatic airplane pilots (autopilot) Gun positioning system Gun positioning system Radar antenna control systems Radar antenna control systems To solve such problems Theory of Servomechanism was developed. To solve such problems Theory of Servomechanism was developed. Requirement of weaponry system during WW-II Requirement of weaponry system during WW-II 9

10. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501)History [servo means slave] [servo means slave] Servomechanism/servo system/servo: System which is slave to command Servomechanism/servo system/servo: System which is slave to command Servo Systems using feedback to control motion, velocity/acceleration of mechanical part to achieve precise movement, positioning Servo Systems using feedback to control motion, velocity/acceleration of mechanical part to achieve precise movement, positioning A servo system typically includes a motor, a feedback sensor, and a controller. A servo system typically includes a motor, a feedback sensor, and a controller. 10

11. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501)History Following theories converged as unified feedback control theory Following theories converged as unified feedback control theory Theory of process control (e.g. in industries: HVAC, mixing etc) Theory of process control (e.g. in industries: HVAC, mixing etc) Theory of servomechanism (e.g. in weaponry systems, position) Theory of servomechanism (e.g. in weaponry systems, position) Theory of cybernetics (e.g. recommender system, NLP, socio- economic systems, intelligent systems) Theory of cybernetics (e.g. recommender system, NLP, socio- economic systems, intelligent systems) Term feedback control is applicable to all three fields Term feedback control is applicable to all three fields 11

12. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Basic terminology Process: Entire system or environment where control is being applied. Process: Entire system or environment where control is being applied. For temp. control: Process is environment where we want to control temperature (room/plant) For temp. control: Process is environment where we want to control temperature (room/plant) Manipulated input: We need to design a controller to get this input Manipulated input: We need to design a controller to get this input How much current flows to fan to control process temperature How much current flows to fan to control process temperature Disturbance: either from outside inside Disturbance: either from outside inside Outside: Door is open Outside: Door is open Inside: Cooking inside Inside: Cooking inside Response variable is specific parameter or quantity within the process/plant that the control system is designed to regulate or maintain at a desired value Response variable is specific parameter or quantity within the process/plant that the control system is designed to regulate or maintain at a desired value 12

13. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Basic terminology Controller: That translates command input to manipulated variable Controller: That translates command input to manipulated variable Controller  Fan regulator: Lets current flow depending upon fan speed number selected on the fan regulator Controller  Fan regulator: Lets current flow depending upon fan speed number selected on the fan regulator 13

14. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Basic terminology Open-loop control system Open-loop control system In the configuration of Fig. 1.3, the controller receives information about the desired value of the controlled output and uses this information as a means of control of the manipulated variables. In the configuration of Fig. 1.3, the controller receives information about the desired value of the controlled output and uses this information as a means of control of the manipulated variables. We as a human understand current temperature and once set fan regulator accordingly We as a human understand current temperature and once set fan regulator accordingly It may not work well in due to disturbances It may not work well in due to disturbances 14

15. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Basic terminology Closed-loop/feedback control system Closed-loop/feedback control system In contrast to open-loop configuration, the configuration of Fig. 1.4 utilizes measurement of the controlled output in order to compare the actual output with the desired output response. The controller then uses this difference as a means of control of manipulated variables. In contrast to open-loop configuration, the configuration of Fig. 1.4 utilizes measurement of the controlled output in order to compare the actual output with the desired output response. The controller then uses this difference as a means of control of manipulated variables. Disturbance input is random Disturbance input is random So, controller is fed-back with controlled output rather than information of disturbance input So, controller is fed-back with controlled output rather than information of disturbance input Thermostat in AC is (measurement/sensor block) Thermostat in AC is (measurement/sensor block) 15

16. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Basic terminology Closed-loop/feedback control system Closed-loop/feedback control system Here controller is said to be robust because it can overcome effect of disturbances Here controller is said to be robust because it can overcome effect of disturbances It is primary requirement of FBCS to make system robust It is primary requirement of FBCS to make system robust Problems: Problems: Sensor may be faulty Sensor may be faulty Frequency of sensor data can cause unstable output Frequency of sensor data can cause unstable output Tradeoff: Tradeoff: (Accurate vs stable output) (Accurate vs stable output) 16

17. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Design approaches of controller Experimental/ad hoc approach (controller tuning) Experimental/ad hoc approach (controller tuning) Sometimes it is difficult to model the process, or maybe; enough information is not available due to non-linear process Sometimes it is difficult to model the process, or maybe; enough information is not available due to non-linear process We depend upon experimental knowledge rather than quantitative data We depend upon experimental knowledge rather than quantitative data We depend upon operator (person) experience about the process We depend upon operator (person) experience about the process Using such experience knowledge, controller is installed and tuned to achieve effective relation between controlled variable and command signal Using such experience knowledge, controller is installed and tuned to achieve effective relation between controlled variable and command signal 17

18. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Design approaches of controller Knowledge base approach Knowledge base approach When mathematical modeling may not be possible then controllers are designed with the help of expert knowledge, rules, and reasoning When mathematical modeling may not be possible then controllers are designed with the help of expert knowledge, rules, and reasoning Example: Programming/AI/logic-based controllers designed without mathematical model or experimental knowledge of current process Example: Programming/AI/logic-based controllers designed without mathematical model or experimental knowledge of current process 18

19. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Design approaches of controller Model based approach/ Analytical approach Model based approach/ Analytical approach When system is complex, controller can't be designed using experimental knowledge or experience When system is complex, controller can't be designed using experimental knowledge or experience To capture the dynamics of system in suitable mathematical form may be differential equations, transfer function or state variable model To capture the dynamics of system in suitable mathematical form may be differential equations, transfer function or state variable model Suitable mathematical model can help to capture the dynamics of system quantitatively. Suitable mathematical model can help to capture the dynamics of system quantitatively. This quantitative information is used to design the controller, and we hope to get better results This quantitative information is used to design the controller, and we hope to get better results In this course we are concerned with model-based control In this course we are concerned with model-based control 19

20. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Design approaches of controller So, we will be doing mathematical modeling of physical systems in the form of differential equations, transfer function or state variable model So, we will be doing mathematical modeling of physical systems in the form of differential equations, transfer function or state variable model Physical systems must follow laws of physics Physical systems must follow laws of physics Mathematical model can be developed using Mathematical model can be developed using (i) Physical laws: (i) Physical laws: (ii) System identification: (ii) System identification: If system is complex, then equations can be developed using experimentation for various inputs and their outputs, and then modeled in the form of equations If system is complex, then equations can be developed using experimentation for various inputs and their outputs, and then modeled in the form of equations We are concerned with modeling using physical laws only We are concerned with modeling using physical laws only 20

21. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Design approaches of controller using mathematical model During 1940~1960 classical methods of design were developed During 1940~1960 classical methods of design were developed Also known as Frequency domain design methods Also known as Frequency domain design methods Nyquist stability criterion Nyquist stability criterion Bode plots Bode plots Root locus plots Root locus plots Used in around 75% of industrial control design Used in around 75% of industrial control design 1960s and onwards modern methods of design were developed 1960s and onwards modern methods of design were developed Also known as State space methods of design Also known as State space methods of design Came into existence for the launching, the maneuvering, the tracking of space vehicles Came into existence for the launching, the maneuvering, the tracking of space vehicles Used for more complex systems such as MIMO systems Used for more complex systems such as MIMO systems 21

22. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Design approaches of controller using mathematical model This course will cover classical methods of design in depth, whereas state space methods will not be discussed from design point of view but simulation. This course will cover classical methods of design in depth, whereas state space methods will not be discussed from design point of view but simulation. 22

23. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system examples Examples Examples Bathroom toilet tank Bathroom toilet tank https://www.youtube.com/watch?v=yEBMUDL0apE&t=55s https://www.youtube.com/watch?v=yEBMUDL0apE&t=55s Automobile Driving Automobile Driving Residential Heating Residential Heating Hydraulic Power Steering Mechanism Hydraulic Power Steering Mechanism Servo System for an Antenna Servo System for an Antenna Speed Control System Speed Control System 23

24. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Bathroom toilet tank Example of FBCS Example of FBCS Plant is water tank Plant is water tank H^ (Height) is command input H^ (Height) is command input H (Height) is controlled output H (Height) is controlled output Outflow is disturbance Outflow is disturbance Inflow of water is manipulated variable Inflow of water is manipulated variable Float and lever mechanism is controller Float and lever mechanism is controller e is error signal that activates controller to generate control variable (u) e is error signal that activates controller to generate control variable (u) 24 u is directly proportional to e u = ( l1/ (l1+l2) ) e l2 SISO system or scalar system

25. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Bathroom toilet tank Example of FBCS Example of FBCS The actuator block is a component that converts the control signal from the controller into a physical action or output that affects the system. The actuator block is a component that converts the control signal from the controller into a physical action or output that affects the system. Actuator is source of water + valve Actuator is source of water + valve 25 Here input command H^ remains constant and it known as setpoint. Such a system is know as regulator system. Systems without human intervention are called automatic control systems. We will cover such systems in this course.

26. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Automobile Driving System MIMO system (Multivariable systems) MIMO system (Multivariable systems) Controlled output Controlled output Heading/direction Heading/direction speed speed Plant: vehicle Plant: vehicle Disturbance: Wind+Traffic Disturbance: Wind+Traffic Input command: Input command: direction of highway direction of highway Speed limits Speed limits Manipulated variable Manipulated variable Steering wheel position Steering wheel position Actuator: Hands Actuator: Hands Accelerator/brake position Accelerator/brake position Actuator: Foot Actuator: Foot 26

27. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Automobile Driving System Basic difference between SISO and MIMO systems lies in the interaction. Here one manipulated variable may affect both controlled variables. That is called coupling between input and output. Basic difference between SISO and MIMO systems lies in the interaction. Here one manipulated variable may affect both controlled variables. That is called coupling between input and output. Here brake can affect speed, and it may affect direction as well. Here brake can affect speed, and it may affect direction as well. Therefore, MIMO systems are difficult to design. Therefore, MIMO systems are difficult to design. 27

28. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Automobile Driving System For simplicity it is assumed that there is negligible coupling effect, and this MIMO system is designed as set of two SISO systems. For simplicity it is assumed that there is negligible coupling effect, and this MIMO system is designed as set of two SISO systems. Same practice is carried out in many industries to simplify design problem. Same practice is carried out in many industries to simplify design problem. Major portion of our course covers SISO systems only Major portion of our course covers SISO systems only 28

29. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Automobile Driving System Dotted portion: Error detection is done by eyes Dotted portion: Error detection is done by eyes Controller is brain of driver Controller is brain of driver Here input command signals are not fixed Here input command signals are not fixed Changing with time Changing with time System is referred to as tracking system or command following system System is referred to as tracking system or command following system Where human is involved in the system is called Man-Machine control system Where human is involved in the system is called Man-Machine control system 29

30. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Hydraulic Power Steering Mechanism https://www.youtube.com/watch?v=em1O8mz7sF0 https://www.youtube.com/watch?v=em1O8mz7sF0 https://www.youtube.com/watch?v=em1O8mz7sF0 This is example of command following or tracking system This is example of command following or tracking system 30

31. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Hydraulic Power Steering Mechanism Modeling and analysis Modeling and analysis For suitable mathematical model first we need suitable physical model For suitable mathematical model first we need suitable physical model Physical model can be obtained in the form of combination of Mass-Spring-Friction elements in a suitable way Physical model can be obtained in the form of combination of Mass-Spring-Friction elements in a suitable way 31

32. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Hydraulic Power Steering Mechanism Block diagram Block diagram Command input Command input Steering wheel angle (theta_r) Steering wheel angle (theta_r) x: spool displacement x: spool displacement Spool displacement is compared with feedback signal z Spool displacement is compared with feedback signal z y: controlled variable y: controlled variable Displacement y Displacement y Plant is piston + load Plant is piston + load Theta_0 is translation signal of controlled variable y Theta_0 is translation signal of controlled variable y 32 In a hydraulic steering system, "load" refers to the resistance or force that the steering mechanism has to overcome to turn the wheels or steering components. This load is influenced by factors such as the weight of the vehicle, the friction between the tires and the ground, the terrain, and the speed at which the vehicle is moving.

33. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Residential Heating System Water is heated and turned into steam in steam boiler Water is heated and turned into steam in steam boiler Depending upon required temperature, steam is sent to room radiator Depending upon required temperature, steam is sent to room radiator 33 Fig. 1.6 Open-loop temperature control system

34. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Residential Heating System When accuracy requirements are higher When accuracy requirements are higher Bimetallic strip (installed in room) Bimetallic strip (installed in room) Metals with different thermal expansion properties Metals with different thermal expansion properties Bend in one direction Bend in one direction Position 1: current flows (plunger up) Position 1: current flows (plunger up) Position 2: current does not flow (plunger down) Position 2: current does not flow (plunger down) 34

35. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Residential Heating System Temperature will oscillate Temperature will oscillate It should oscillate with suitable limits plus minus 2C is ok It should oscillate with suitable limits plus minus 2C is ok 35

36. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: Residential Heating System 36

37. Slide # Department of Electrical Engineering, Sukkur IBA University Advanced Control Systems (EE-501) Control system structure: 37