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Introduction to

Control Engineering

at Power Plants

Lesson 1

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1 - Power plant processSchematic of a coal-fired steam power plant

Page 2

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1 - Power plant processSchematic of a combined cycle power plant

Page 3

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Page 4

1 - Power plant processProcess and Instrumentation Diagram with KKS codes

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1 - Power plant processIdentification system for power plants : KKS

Page 5

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1 - Power plant processIdentification system for power plants : KKS

Page 6

Ex: 1 LDA04 AP001 KP01

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1 - Power plant processIdentification system for power plants : KKS

Page 7

Ex: 0 BFA03.03

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1 - Power plant processIdentification system for power plants : KKS

Page 8

Ex: 1 UHA04.01

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1 - Power plant processCentral Control Room Layout Concept Example

Page 9

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1 - Power plant processCentral System Room Layout Concept Example

Page 10

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1 - Power plant processExamples of process engineering redundancy

Page 11

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1 - Power plant processPower plant components (KKS codes)

Page 12

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1 - Power plant processPower plant components (KKS codes)

Page 13

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2 - InstrumentationDirect measuring circuits (KKS)

Page 14

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2 - InstrumentationVarious types

Page 15

Level

Capacitance Ultrasonic Radar

Pressure Temperature

Rail Head

Field

Positioner

Electropneumatic

Flow

Ultrasonic

Clamp On Coriolis Vortex

Magnetic

Analytics Weighing

Belt ScalesDelta-P

Vibration and

ExpansionPosition

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2 - InstrumentationField Instrument Mounting Racks

Page 16

Furnace pressureDrum level

Suction & discharge pressure

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2 - InstrumentationField Instrument Mounting Racks

Page 17

Furnace pressureDrum level

Suction & discharge pressure

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2 - InstrumentationField Instrument Measuring Chain

Page 18

Furnace pressure

Drum level

Suction & discharge pressure

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2 - InstrumentationField Instrument Hook Up

Page 19

Furnace pressure

Drum level

Suction & discharge pressure

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3 - Signal TypesDigital signals

Page 20

Digital signals are used to represent items that only have two states,

such as ON (binary 1) or OFF (binary 0) states.

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3 - Signal TypesAnalog signals

Page 21

Analog signals have variable states in contrast to digital signals.

Input signals: Position feedback,temperature, pressure, level...etc.

Output signals: Set points (for VFDs, proportional control valves...etc.)

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3 - Signal TypesRTD & Thermocouples

Page 22

RTDs (Resistance Temperature Detector) and thermocouples are used

for temperature measurement. These signals have variable states as

analog signals.

Thermocouple RTD

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4 - Signal LoopsRelay & Contact Types

Page 23

Relay Socket

Bracket

Label

LED

Relay Set

Coil C/O Contact

Circuit Diagrams

Coil NO Contact

NO: Normally open

NC: Normally close

C/O: Changeover

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Page 24

4 - Signal LoopsDI signals

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Page 25

4 - Signal LoopsDI signals

Single Contact Changeover Contact Electronic Sensor

24V 24V

24V

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Page 26

4 - Signal LoopsDO signals

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4 - Signal LoopsAI signals (Voltage)

Page 27

Range Mod. Set

A

B

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4 - Signal LoopsAI signals (Current)

Page 28

Range Mod. Set

D

C

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4 - Signal LoopsAI signals (Resistance transducers or RTDs)

Page 29

Range Mod. Set

A

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4 - Signal LoopsAI signals (Thermocouples)

Page 30

Range Mod. Set

A

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4 - Signal LoopsAO signals (Voltage)

Page 31

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4 - Signal LoopsAO signals (Current)

Page 32

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4 - Signal LoopsSymbols and terms on drawings

Page 33

Signal module Terminal Device

DCS cabinet Field

Cable

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4 - Signal LoopsExample drawings (Digital signals)

Page 34

DO signal connection

Relay coil

DI signal connection

Relay contact

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4 - Signal LoopsExample drawings (Analog signals)

Page 35

AI signal connection (4-20mA_2wire)

AI signal connection (4-20mA_4wire)

AO signal connection (4-20mA)

24V

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5 - CablesPower cables

Page 36

Outer sheath Armour Filler Insulation Conductor

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5 - CablesInstrumentation & Control Cables

Page 37

Outer sheath Overall screen Individual screen Insulation Conductor

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5 - CablesCommunication Cables

Page 38

Profibus DP Industrail Ethernet Fiber Optic

Multimode fiber cable distance <3km

Single mode fiber cable >3km

Cat6 (eight cores) cables up to 1Gbit/s

Cat5 (four cores) cables up to 100Mbit/s

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Page 39

Thank you