1. New Concepts in Supercritical Turbines
WELCOME TO
Presentation on
New Concepts in Supercritical Turbines
Sanjoy Bhattacharya
Dy. Genl. Manager, BHEL, Hardwar

2. Developments in Steam Turbine

3. CROSS SECTIONAL ARRANGEMENT OF
500 MW STEAM TURBINE
THREE CYLINDER TURBINE

4. Introduction of New Rating Sets
Major Objectives
Bring down equipment cost per MW
Having more Efficient & Reliable product
Utilize available Steam turbine modules
Provide Higher competitiveness
New Rating to compete with Chinese/ New Indian firms

5. Built from proven modules of existing 500 & 250 MW
600MW Steam turbine:
Built from proven modules of existing 500 & 250 MW
OPTIONS
HP Turbine with Extraction & 565 Deg C HRH Temp
HP Turbine without Extraction & 537 Deg C HRH Temp
Module Combination
HP: H30-100
IP : M30-63
LP : N30-4x6.3
Salient features:
4 cylinder turbine (2 LPs)
HP turbine with Extraction connection for 565 HRH Temp
IP turbine suitable for 537/565 0C inlet temp.
Steam parameters
170 ata / 537 0C/ ( ) 0C
Orders for 2 sets - N Chennai, 2 sets –JITPL, 1 set -APGENCO & 2 sets Singareni received.
Orders for 4x600 MW Raigarh-III (Jindal), 2x600 MW Malwa, 2x600 MW each Avantha / Videocon/ Visa Raigarh/ DB Power & 1 x 600 MW Rayalaseema received .

6. Steam Turbine 600MW Steam Turbine
600 MW Sub critical Sets
Steam Turbine
Design Changes from existing 500 MW sets :
HP module variant with Extraction
New Flow path in HP, IP & LP Turbines (with Advanced blading)
Matching modifications in Rotors & Inner Casings
New Bearing pedestal between 2 LP cylinders
New design of Cross Around Pipe & its support
Enhanced governing characteristics
600MW Steam Turbine

7. 500/ 600 MW SUB CRITICAL CYCLE
WITH 2 HP HEATERS, 3 LP HEATERS

8. Introduction of Steam Turbine with supercritical parameters
As the fluid pressure increases, Latent Heat (Enthalpy of Steam –Enthalpy of Water) reduces.
At Critical point it becomes zero.
In physical terms at this pressure water transforms to steam spontaneously.
4.3 %
SUPER CRITICAL STEAM PARAMETERS:
PARAMETERS MORE THAN CRITICAL STATE
STEAM PRESSURE > BAR
STEAM TEMPERATURE > Deg C
ULTRA SUPERCRITICAL PRESSURE( 300 BAR)
Improvement
Subcritical
170 ata / 537 °C / 537 °C
Super Critical
247 ata / 565 °C / 593 °C
INCREASE IN PRESSURE & MAIN AND REHEAT TEMP. > 537 Deg C
RESULTS IN SIGNIFICANT IMPROVEMENT IN HEATRATE

9. Supercritical Cycles
Steam Power plant efficiency increases with increase in steam pressure and temperature.
Power plant Cycles operating above critical pressure (221.2 bar) are classified as Supercritical cycles
With higher cycle efficiency, the supercritical cycle offers the advantage of ‘burn less fuel for the same output’ and lower emission.
It is known that the increase in Pressure & Temperature increases the thermal Efficiency.
In a thermodynamic Rankine Cycle, steam pressure above 224 kg/CM2 and temperature above 374 deg C are referred as supercritical parameters.
Among the various advanced technological options available for coal power this is the most proven and is already in wide commercial use and can be readily adopted.
The steam at kg/cm2 and C is said to be in critical state. Thermodynamic cycles which operate at parameters above critical point are called supercritical cycles. At critical point, density of water and steam are same. Further latent heat at this point is zero which means that there is no steam-water mixed phase. Thus boilers operating under supercritical parameters do not have boiler drum that separates steam from water. The super critical boilers employ steam pressures above critical pressure.
Lesser Pollutants – SOX , NOX & CO2

10. IMPROVEMENT IN EFFICIENCY WITH INCREASING INLET PARAMETERS FOR STEAM TURBINES

11. PARAMETERS FOR BHEL STEAM TURBINES
UNIT
500 MW
660 MW
800 MW
MS PRESSURE
ATA
170
247
MS TEMPERATURE oC
537
565
MAIN STEAM FLOW
T/HR
1500
1919
2380
REHEAT PRESSURE
40.5 56 60
RH TEMPERATURE
593
FINAL FEED WATER TEMP.
253
290

12. Typical Supercritical TG Cycle

13. REGENERATIVE CYCLE CONFIGURATION
TWO EXTRACTIONS FROM IPT
FOUR LP HEATERS
DEAERATOR
ONE EXTRATION FROM HPT
THREE HP HEATERS
250% TURBINE DRIVEN BFP
ONE MOTOR DRIVEN BFP

14. STEAM TURBINE MODULE CONFIGURATION
500 MW
660 MW
800 MW
HP TURBINE
H30-100
IP TURBINE
M30-63
M30-100
LP TURBINE
N30-2 x 10
N30-2 x 12.5
N30-4 x 8
HP VALVES
2 x FV320
2 xFV250A
IP VALVES
2xAV560
2xAV560A

15. View of 660 MW Steam Turbine

16. 660MW Steam turbine: With Supercritical parameters
Impulse tilted blade in HP & IP turbines
Heat Shield at the inlet section
Increase in wall/pipe thickness
Material with improved properties for higher steam temperature
Optimum flow path
Salient Feature:
New series of HP & IP modules for supercritical parameters
Higher size LP module
247 ata Main Steam Pressure
565 0C Main Steam Temperature
593 0C Hot reheat Temperature
Order for 2x660 MW Barh- II/ DB Power & 3 x 660 Bara & Lalitpur TPP
Other expected tenders 1 x 660 MW JITPL Angul, Jhabua Seoni, etc

17. View of 800 MW Steam Turbine

18. 800MW Steam turbine Salient features: 4 cylinder turbine (2 LP’s)
Generator
LP Turbine 2
LP Turbine 1
IP Turbine
HP Turbine
Condenser
Salient features:
4 cylinder turbine (2 LP’s)
New series of HP, IP & LP modules for super critical parameters
Orders for Yermarus (2x800 MW), & Edlapur (1x800 MW), JV between KPCL and BHEL
Order expected for NTPC 2 x 800 MW Gajmara TPP & Udangudi (2x800 MW), JV between TNEB and BHEL

19. 800MW Steam turbine: General Arrangement

20. CROSS SECTIONAL ARRANGEMENT OF 800 MW STEAM TURBINE
FOUR CYLINDER TURBINE

21. CONSTRUCTIONAL FEATURES OF HP TURBINE FOR 800 MW
Barrel in two pieces
SINGLE FLOW, DOUBLE SHELL
OUTER CASING BARREL TYPE IN TWO PIECES
INNER CASING AXIALLY SPLIT
MONO BLOCK DRUM TYPE ROTOR

22. CONSTRUCTIONAL FEATURES OF IP TURBINE FOR 800 MW
DOUBLE FLOW, DOUBLE SHELL CASING
MONO BLOCK DRUM TYPE ROTOR
STEAM ADMISSION IN L/H FROM BOTH SIDES
EXTRACTIONS CONNECTIONS IN LOWER HALF ONLY
VALVES BOLTED TO THE CASING IN LOWER HALF

23. Diagonal Impulse Blading
HPT FIRST STAGE

24. IP Turbine : HEAT SHIELD WITH VORTEX BORES

25. CONSTRUCTIONAL FEATURES OF LP TURBINE FOR 800 MW
DOUBLE FLOW, DOUBLE SHELL
OUTER CASING FABRICATED , INNER CASING CASTINGS
MONO BLOCK ROTOR

26. SECTIONAL DETAILS OF LP TURBINE FOR 660 / 800 MW

28. SECTIONAL DETAILS OF LP TURBINE FOR 660 / 800 MW

29. PUSH ROD ARRANGEMENT

30. LP TURBINE INNER CASING SUPPORT DETAILS FOR 660 / 800 MW

31. GOVERNING THROTTLE CONTROLLED GOVERNING WITH
HIGH PRESSURE ELECTRO HYDRAULIC COMPACT ACTUATORS (160 BAR)

32. Turbine Governing EXISTING DESIGN(500 MW) NEW DESIGN(660 MW)
THROTTLE GOVERNING
ELECTRO HYDRAULIC
(WITH 32 BAR PRESSURE)
NEW DESIGN(660 MW)
THROTTLE GOVERNING
HIGH PRESSURE ELECTRO HYDRAULIC GOVERNING
(ACTUATORS WITH PRESSURE OF 160 BAR)

33. Turbine Governing ADVANTAGES OF EHA BASED SYSTEM
Simplified plant layout due to overall compact size
Control oil piping reduced
Faster response due to state of art electronic control and protection system
Better interconnection with other system
Ease of operation and maintenance
Valve room is avoided

34. Turbine Governing EHA SYSTEM CONSISTS OF
HYDRAULIC POWER SUPPLY UNIT
HPSU CONTROL UNIT
VALVES ACTUATORS
CONTROLLERS
PROTECTION SYSTEMS

35. OVERHAULING

36. SUMMARY
Proven Supercritical technology in collaboration with M/s Siemens
Steam Parameters up to 300 bar / 600°C / 620°C
Modular Turbo set design to fit best customer needs
High reliability & Availability
Long Inspection intervals
High efficiency by using modern CFD tools for flow path & blades

37. Thank you for a Patient hearing…………