working of lift

1. PRESENTED BY:
K.B.S.Gangadhar (08B21A0248)
J.V.V.RamaRao (09B25A0203)
R.Sekhar (08B21A0231)
MD.Khader vali (08B21A0211)

2. PLANT DESCRIPTION
ELECRICAL EQUIPMENTS
PROTECTION SCHEMES
SPECIFIED RATINGS
ALTERNATIVE SYSTEMS
DC& UPS SYSTEM

3.  LOCATION : SAMALKOT
 CAPACITY : 469MW
 OPERATION : COMBINED CYCLE
 INPUTS : RELIANCE KG BASIN
 OUTPUTS : VEMAGIRI SUBSTATION
APTRANSCO
 EQUIPMENT : ALSTOM

4.  COMBINATION OF TWO CYCLES
GAS CYCLE
STEAM CYCLE
 TWO GAS TURBINES
 ONE STEAM TURBINE
 TWO HRSG SYSTEMS
 MORE EFFICIENT
 ECO FRIENDLY
 NO WASTAGE

5. PRINCIPLE:
In a combined cycle power plant, a gas turbine generator generates
electricity and the heat in the gas turbine’s exhaust gases is used to generate
steam in a Heat Recovery Steam Generator that in turns used to generate
electricity with steam turbine generator which enhances the efficiency in
power generation.

6.  PRINCIPLE
 DOMINANT ROLE
 CONSISTS OF STATOR AND ROTOR
 NEED OF PROTECTION
 GAS TURBINE GENERATOR(GTG)
 STEAM TURBINE GENERATOR(STG)
 RATINGS
GTG STG
RATED VOLTAGE 15.75 KV 11KV
RATED CURRENT 7698 A 12543 A
POWERFACTOR 0.8 0.8
COOLING TYPE WATER WATER

7. ROTOR:
 ROTATORY PART IN THE MACHINERY
 SPECIFIED DETAILS OF ROTOR
Diameter of body 1050 mm
No. Of wound slots per half pole 8
Conductor material CuAg
STATOR :
 Supports armature core with laminations.
 SPECIFIED DETAILS OF STATOR:
 Core length 4620mm
 Inside diameter of core 1150mm
 No. of slots 60

8.  Core losses
Hysteresis losses-reversal of magnetization
Eddy current losses-induced emf
 Stray losses
1.Mechanical losses
friction and windage losses
2.Magnetic losses
Losses value( kw )
 Core losses 381
 Stator copper losses 230
 Stray load losses 275
 Rotor copper loss 422
 Excitation losses 23
 Windage losses 822
 Bearing losses 95
 Total losses 2248

9. During fault and abnormal conditions
 Generator Differential Protection.
 Loss of excitation
 Overvoltage Protection
 Earth fault protection
 Negative Sequence Protection
 Over current/Under voltage Protection.
 95% Stator Earth Fault protection
 Reverse Power protection
Cooling system:
 CACW means circulating air circulating water.
 For circulation of the air two fans are mounted on both ends of
the generator rotor.

10.  PRINCIPLE -ELECTROMAGNETIC INDUCTION
 MAGNETICAL COUPLING
 DESIRED VOLTAGE LEVELS FOR MACHINERY

11. Description units
No. of phases 3
Rated power 210MVA
No. of windings per phase 2
Rated Voltage(no load) on
H.V side 400KV
Rated Voltage(no load) on
L.V side 15.75Kv
Rated Current on H.V side 303.7A
Rated Current on L.V side 7707.1A
Rated frequency 50Hz

12. TYPES OF TRANSFORMERS
 step-up transformer
 step-down transformer
 current transformer
 potential transformer
 ideal transformer
Cooling system
 Oil Forced Air Forced unit
 Five units coolers each having 25% cooling capacity
 4 working and 1 standby with selective switching
Protection system
 Differential Protection Buchhlolz Relay
 Over current Earth Fault Protection

13. Mv system:
 Bus-duct of GT generator via station service
transformer with 6.6kv
 low resistance earthed system
 Vaccum circuit breaker(VCB)
 Microprocessor based protection system
Lv system :
 Rating up to maximum 250 KW, including the UPS system,
chargers & batteries.
 Automatic dead-bus changeover
 motors rated 160-250 KW CB are provided motors rated < 160
KW, contactor-controlled feeders

14.  ONE AND HALF BREAKER SWITCHING SCHEME
 400 KV SWITCHYARD
 STARTUP POWER SUPPLY FOR BACK CHARGING

15. INTERCONNECTION PURPOSE
Loads and source of electrical power systems
Generators and main transformer
Types of bus bars according to voltages
Voltage levels Bus bars
Low Rigid
Medium Rigid, insulated phase,sf6
High Rigid,strain,sf6

17.  CIRCUIT BREAKERS
SF6 CIRCUIT BREAKER
Rated voltage 420v
Normal current 2000A
 ISOLATORS
EARTH SWITCH
Operating Mechanism Manual
Control 220V DC
 SURGING ARRESTORS
 LIGHTNING ARRESTORS

18. BREAKER CONTROL
 Line bay breaker
 Steam Turbine Generator Transformer Bay
 Gas Turbine Generator Transformer Bay
 Local Control
Remote Terminal Unit
 A RTU has been envisaged for facilitating the data transmission
such as MW, MVAr, MWH and MVArH of each line to the Remote
Load Dispatch Center through the Microwave Links, as planned and
will be supplied by AP Transco.
 In addition, the RTU will be able to collect and communicate the
switchyard status and data to SCADA system which will be supplied
by APTransco. The RTU will be located in the switchyard control
room.

19.  1 Line bays protection
Main I protection
Main II protection
 Generator Transformer bays
Common Protections:
 For all the bays, following additional protections and relays will be
provided.
◦ Local breaker backup protection (LBB)
◦ Trip Circuit Supervision for each trip coil
◦ DC supply supervision
◦ Pole discrepancy protection
◦ Anti pumping device for breaker closing
◦ All auxiliary relay as per system requirement

20. STANDBY DIESEL GENERATOR
The standby diesel generator is connected to the LV switchgear. The diesel generator is a
rated 625 KVA in order to feed the essential auxiliaries for the safe shut down of the plant
in the event of loss of normal AC power. This is used to charge the station batteries. The
standby diesel generator set is automatically started upon detection of loss of normal AC
power

21. PARTS OF DIESEL GENERATOR
Generator Controller
Fuel Tank
Automatic Voltage Regulator
TYPES OF DIESEL GENERATORS
The TS25 Baldor Standby Generator
The 10,000 Watt Aurora Standby Generator

22. DC&UPS SYSTEM
220V DC SYSTEMS:-
Each DC system consists of battery and battery charger, and associated D.C. distribution
boards. The whole battery system is sized for one (1) hour ST shut down operation. The safe
shutdown is carried out bye the DC system in conjunction with the standby diesel generator
set. For meeting this 2*50% battery banks of lead acid tubular type are provided .

23. UPS:-
240V AC uninterruptible power supply is provided bye two inverters with automatic static
changeover switches. During normal operation the UPS is supplied through the inverters
and the chargers which are connected to the respective low voltage switchgear.

24.  Here overall view of the combined cycle power plant suggests
the best generation of power and gives better efficiency by
using the gas and steam cycles
 Electrical equipments such as gengrators,transformers,circuit
breakers, isolators and most of the equipments been observed
and their workings has been observed. Finally there is a far
distance between the practical scenario and the bookish
knowledge and we linked between the both conditions.

25. ANY QUERIES ? ? ? ?
THANK YOU