PPt on Mark Vi Control

(1)

OVER VIEW OF GTG PLANT AND

CONTROL OF TURBINE

(2)

MAIN GB ALTERNATOR COMPRESSOR TURBINE & COMBUSTOR AUX GB STARTING DE

(3)

Gas Turbine principle

cooler Heat rejected Heat added 1 2 3 4 Compressor Heater Turbine

(4)

Description

 At point 1 cold gas enter a compressor to raise pressure_{At point 1 cold gas enter a compressor to raise pressure}  At point 2 the gas passes to the heater where _{At point 2 the gas passes to the heater where}

temperature of gas is raised

 At point 3 the hot gas enters the turbine where it _{At point 3 the hot gas enters the turbine where it}

expands to a lower pressure. The shaft work developed

by turbine flows in two direction.

 At point 4 the exhaust gas flows to cooler where heat is _{At point 4 the exhaust gas flows to cooler where heat is}

rejected and gas is restored in initial position

(5)

Brayton /Joule cycle

Volume Pressure

1

2 3

4

(6)

Rankine cycle

Volume Pressure 1 2 3 4 2-3 (Boiler) 3-4 (Turbine) 1-2 (BFP) 4-1 (Condenser)

(7)

Open cycle gas turbine

1 2 3 4 Compressor Turbine Combustion chamber Fuel

(8)

Salient points

 The source of energy is normally the combustion of fuel _{The source of energy is normally the combustion of fuel}

in air

 In closed cycle, gas turbine also product of combustion _{In closed cycle, gas turbine also product of combustion}

of fuel and air may be passed through the heater

 In open cycle cooler is not required_{In open cycle cooler is not required}

 The heater is replaced by combustion chamber and fuel The heater is replaced by combustion chamber and fuel

is burnt directly in air stream

(9)

Open cycle gas turbine (With heater)

1 2 3 4 Compressor Turbine

Air from atmosphere

Product of combustion to atmosphere Heat exchanger

Combustion chamber Fuel

(10)

CONTROL SYSTEM

A control scheme of a gas turbine attempts to control the A control scheme of a gas turbine attempts to control the following

following

 SPEED_SPEED

 TEMPERATURE (COMBUSTOR OUTLET)TEMPERATURE (COMBUSTOR OUTLET)  LOAD_LOAD

 START UP CHARACTERISTICS_{START UP CHARACTERISTICS}  ACCELERATION CONTROL_{ACCELERATION CONTROL}

Above characteristics are achieved by modulating fuel Above characteristics are achieved by modulating fuel flow. Control signal ultimately acts on the fuel valve

(11)

CONTROL SYSTEM

 SPEED_SPEED: The speed control loop controls the speed of _{: The speed control loop controls the speed of}

the turbine by controlling the fuel flow . Speed control

have speed sensing as input to the controller.

 TEMPERATURE_TEMPERATURE: Materials used in the hot gas path of _{: Materials used in the hot gas path of}

gas turbine are stretched much closer to their limits than

any other machine. The control system takes design

temperature of hot flue gas path material as set point.

 LOAD_LOAD: The control loop takes the MW as the set point. _{: The control loop takes the MW as the set point.}

The control loop also interferes when rate of loading

exceeds a certain point as turbine is loaded fast the

damage of the component may occur

(12)

CONTROL SYSTEM



START UP CHARCTERISTIC

: The control

system brings the gas turbine from zero

speed to operating speed using preset level

of fuel flow through automatic sequencing of

control signals to the accessories, starting

device and fuel control system

(13)

CONTROL SYSTEM



ACCELERATION CONTROL

: One critical

component of the turbine start sequence is

the acceleration to synchronous speed. A

design acceleration rate must be

maintained throughout start up to limit

stress on turbine parts.

(14)

MARK VI CONTROL SYSTEM



The main function of mark VI control

system are



Speed control during start up



Turbine load control during normal

operation on the grid



Protection against turbine over speed on

loss of load

(15)

MARK VI CONTROL SYSTEM



It runs on PC based work station using MS

window client server architecture.



HMI provides operator display and control for

mark VI turbine controller

HMI contains a number of product feature



Dynamic graphics



Alarm display



Process variable trending

_{Process variable trending}



Point control display (For maintenance)

_{Point control display (For maintenance)}



HMI access security

(16)

COMMUNICATION

PLANT DATA HIGHWAY

UNIT DATA HIGHWAY HMI SERVERNODE

I/O BOARD

UCVx CONTROLLER

DCS ETHERNET GSM DCS ETHERNET MODBUS

(17)

MARK VI TMR CONFIGURATION

Ethernet _{< R> CONTL MOD}

< S> CONTL MOD < T> CONTL MOD X Y < P> PROT MOD TO DCS

Primary Controller Backup Protection To other GE control sys Software Voting PS PS PS

(18)

Primary ControllerPrimary Controller  ControlControl

 ProtectionProtection  MonitoringMonitoring

<R>, <S>, <T> are Control processor<R>, <S>, <T> are Control processor

Backup ProtectionBackup Protection

 Emergency over speedEmergency over speed  Synchro check protectionSynchro check protection

(19)

MARK VI BOARDS

 I/O Terminal Board_{I/O Terminal Board}  I/O Board_{I/O Board}

 Processor Card_{Processor Card}

 Communication Card_{Communication Card}

 Protective Processor _{Protective Processor}<X>, <Y>, <Z>_{<X>, <Y>, <Z>}  Rack Power SupplyRack Power Supply

(20)

MARK VI I/O

General Purpose I/OGeneral Purpose I/O

 Contact Input_{Contact Input}  Relay Output_{Relay Output}  Analog I/O_{Analog I/O}

 Thermocouple Inputs_{Thermocouple Inputs}  RTD inputs_{RTD inputs}

Turbine specific I/OTurbine specific I/O

 Vibration Inputs_{Vibration Inputs}  Speed Inputs_{Speed Inputs}

 Servo channels for control valves (LVDT or LVDR )_{Servo channels for control valves (LVDT or LVDR )}  Flame Inputs_{Flame Inputs}

(21)

MARK VI COMMUNICATION

External CommunicationExternal Communication

 HMI to Mark VIHMI to Mark VI  HMI to DCSHMI to DCS

Internal CommunicationInternal Communication

 VCMI & Control processorsVCMI & Control processors  DCMI to I/O boardsDCMI to I/O boards

 I/O signal flowI/O signal flow

 Unit data Highway (UDH)Unit data Highway (UDH)

 Ethernet network between controllers and HMIEthernet network between controllers and HMI  Plant data Highway (PDH)Plant data Highway (PDH)

(22)

IONET



IONet is Ethernet network used to

communicate data between the VCMI

communication board in control module,

the I/O boards and three independent

sections of protection module



IONet also communicate data between

controllers in TMR system

(23)

CONTROL SYSTEM TOOLBOX

 Window based application used to configure & maintain Window based application used to configure & maintain

Mark VI control equipment Mark VI control equipment

 Primary function includesPrimary function includes

 Graphical based editor for configuring application code_{Graphical based editor for configuring application code}  Block macros and module library support_{Block macros and module library support}

 Live data block flow diagramsLive data block flow diagrams  On line code changeOn line code change

 On line help filesOn line help files

 I/O configuration & monitoringI/O configuration & monitoring

 Signal management and signal trendingSignal management and signal trending  Report GenerationReport Generation

(24)

PASSWORD ADMINISTRATION

 0-Level: Read only like view, monitor live data _{0-Level: Read only like view, monitor live data}

 1-Level: All function allowed in 0-Level and Change _{1-Level: All function allowed in 0-Level and Change}

Controller Variables and signals and drive advanced

maintenance like change the value of variable, force

signals in a controller

 2-Level: All function allowed in 0 & 1 Level and full 2-Level: All function allowed in 0 & 1 Level and full

controller access and drive advanced maintenance like

make code change, download,put in database and get

from data base

 3-Level: Drive Block Area and Menu maintenance like _{3-Level: Drive Block Area and Menu maintenance like}