CONTROL SYSTEMS Introduction Class

• Team of InstructorsHaripriya

Madhuri Bayya

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Control S

ystems

Destination point

Starting Point

Prescribed path

Definition of control System

• It consists of subsystems and processes assembled for the purpose of controlling the outputs.

• For example in a furnace fuel valves, fuel valve actuators and thermostats acts as subsystems

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Uncontrolled System Example

• Nuclear fission reaction:• It occurs when a nucleus of a heavy atom

captures a neutron.

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Controlled system Example

• Control rods are used in nuclear reactors to control the fission rate.

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Open loop Control System

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Nuclear reaction

Desired power output 10 MW

Actual power output 8 MW

Closed loop Control System

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Nuclear reaction

Desired power output 10 MW

Actual power output 8 MW

Error acts as input

Some examples of control systems

• Temperature• Liquid Level• Speed

Manual feedback control

of a thermal system

Steam

Drain

Thermometer

R

Hotwater

Cold water

Automatic feedback control

of a thermal system

RSteam

Controlvalve

Automaticcontroller

Temperaturemeasuring device

Hotwater

DrainCold

water

Liquid - level control system

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ControllerPneumatic

valve

Inflow

Outflow

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Speed Control examples

Fig.8 Open Loop Control of a turntable Fig.9 Closed Loop Control of a turntable

Applications

• Control Engineering– Foundations from feedback theory– Aeronautical, civil, Mechanical, Electrical,

Chemical, Environmental– Not limited to any engineering disciplines

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Applications

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• Control systems are found in all sectors of industry– Quality control of manufactured products– Automatic assembly line– Machine-tool control– Space technology and weapon systems– Robotics– Computer control– Transportation systems– Power systems– And many others

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Handout discussion

• Modeling of physical system• Time domain analysis• Frequency domain analysis

Text books:• Main text book:

– Nagrath I. J. and M. Gopal, Control Systems Engineering, New Age International (P) Limited, 5thed, 2007.

•  Reference Text book:– Kuo, B. C., and Golnaraghi, F., Automatic

Control Systems,John Wiley & Sons, 8thed, 2003.

– Dorf, R. C., and Bishop, R. H., Modern Control Systems, Addison Wesley, 7thed, 1995.

EvaluationComponent Duration Weightage

(%)Marks Remarks

Test I 60 min 20 60 CB

Test II 60 min 20 60 CB

Assignments - 20 60 OB

Comprehensive Exam.

3 hours 40 120 CB