Turbine Stress Evaluator

TURBINETURBINE

STRESSSTRESS

EVALUATOREVALUATOR

[T S E][T S E]

S. Mundle. DGM. CW

T S E (cont’d)T S E (cont’d)• IMPORTANT FOR TURBINE OPERATION

o To GUIDE THE OPERATOR during

o START UP & SHUTDOWN OPERATION

WITHOUT STRESSING THE TURBINE

PREVENTING FATIGUE

T S E (cont’d)T S E (cont’d)• INPUTS TO T S E:-

‡ WALL TEMPERATURE MEASUREMENT

(TSE THERMOCOUPLES – Ti / T100 )

‡ MEAN TEMPERATURE MEASUREMENT

(TEMPERTAURE – Tm / T50)

‡ TURBINE SPEED

‡ ACTUAL MW LOAD

T S E (cont’d)T S E (cont’d)

• COMPUTING CHANNELS:

• HP STOP VALVE

• HP TURBINE SHAFT

• IP TURBINE SHAFT

T S E (cont’d)T S E (cont’d)• INDICATING AND RECORDING VALUES:

• BARGRAPH INDICATOR(back

up panel)

• MMI + TG DCS

MINIMUM TEMP MARGINS

ACTUAL LOAD, LOAD MARGINS, SPEED,

TEMP MARGINS, TEMPERTAURES.

T S E (cont’d)T S E (cont’d)• IMPORTANCE OF MARGINS

• THERMAL STRESS CAN OCCUR:

DURING STARTUP

• MARGIN INDICATES THE THERMAL STRESS IN TURBINE

STRESS OCCURS WHEN MARGIN IS CONSUMED

LOADING OF TURBINE

! ZERO MARGIN IS AVAILABLE

T S E (cont’d)T S E (cont’d)

• How to Re-gain MARGINS ?

Bring Changes in:

Steam Temperature

Steam Flow

Steam Pressure

T S E (cont’d)T S E (cont’d)

• SYSTEM DESCRIPTIONS:

– It is a µP (Procontrol ‘P’ ) Based System

– Two Separate DC Supply

– Analog & Binary Signals are exchanged with

other system.

T S E (cont’d)T S E (cont’d)

• FUNCTIONS

TT100

T50

+

TpermU

TpermL

Upper Temperature Margin [dTu]

Lower Temperature Margin [dTl]

Load

MW

Function Generator

Upper Load Margin

Lpper Load Margin

T S E (cont’d)

T100FUNCTION GENERATOR

T50

• SHAFT TEMPERATURE SIMULATION [for HP / IP Turbine Shaft]

SHAFT TEMPERTAURE DIRECT MEASUREMENT NOT POSSIBLE

T S E (cont’d)T S E (cont’d)

Upper

Temp

Margin

HP Computing Channels

Lower

Temp

Margin

IP Computing Channels

Upper

Temp

Margin

Lower

Temp Margin

MIN SELECTION MIN SELECTION

Upper Temp

Margin

Lower Temp

Margin

HP Stop Valve Body

Upper

Temp

Margin

Lower

Temp

Margin

ADMISSION

TURBINE

T S E (cont’d)T S E (cont’d)SIGNAL EXCHANGE:

SIGNALS RECEIVED

Turbine Speed

GENERATION MW

SIGNALS SENT

Upper Temp

Margin

Lower Temp

Margin

Turbine Controller

T S E (cont’d)T S E (cont’d)SIGNAL EXCHANGE (Cont’d..)

Shaft Temperature ( Simulated) Upper & Lower Tem Margins

Actual Load / Speed

Upper & Lower Load Margins

RECORDER

T S E (cont’d)T S E (cont’d)

SELF MONITORING OF THE SYSTEM

DYNAMIC MONITORING OF THE SYSTEM

T

t>

Pre-determined gradient

[T= Temperature & t = Time]

T S E (cont’d)T S E (cont’d)

FAULTS & ALARMS:

• Failure of Thermocouples• Dynamic Alarm

• ATRS & Turbine Controller

THANK YOU !