tpp vizag steel plant

1. THERMAL POWER PLANT
OBJECTIVES : -
• To Supply uninterrupted Cold Blast to Blast Furnaces as per
Furnace requirements .
• To supply uninterrupted Essential Power.
• To supply 13 ata process steam for other units of Steel Plant.
• To supply quality DM water to meet both internal and plant needs.
• To supply Chilled Water to meet both internal and plant needs.
• To Maintain Power Generation for meeting the Plant Load

2. ENERGY CONSUMPTION : -
SPECIFIC POWER CONSUMPTION : 600-650 kWh / Ton of
saleable steel
AVERAGE POWER DEMAND : 227 MW( 3 MT ) &
470 MW (6.3 MT)
POWER REQUIREMENT: - 3MT / 6.3 MT
Average Load : 227 / 470 MW
Peak Load : 260 / 500 MW

3. SOURCES OF POWER AS ON DATE : -
• CAPTIVE POWER PLANT
• INSTALLED CAPACITY = 402.5 MW
• STATE ELECTRICITY GRID
• CONTRACT MAXIMUM DEMAND = 185 MVA

4. Captive Generation Sources (As on Date) :
• TOTAL INSTALLED CAPACITY = 402.5 MW
• Thermal Power Plant (315 MW)
• COB-4 PP (14 MW)
• COB-4 PP: Coke Oven Battery-4 Power Plant
• Back Pressure Turbine Station (15 MW)
• Gas Expansion Turbine Station (24 MW)
• Top Pressure Recovery Turbine (14 MW)
• Sinter Heat Recovery Power Plant (20.6 MW)

5. MAIN EQUIPMENTS OF TPP : -
• Boilers (6 No’s)
• Turbo-Generators (5 No’s in MMB)
• Turbo-Blowers (4 No’s)
• Chemical Water Treatment Plant
• CDCP Boilers (16 No’s)
• Back Pressure Turbine Station (2 TGs) & CWP-1
• Chilled Water Plant -2
• Gas Expansion Turbine Station (2 TGs)
• COB-4 PP (1 TG)
• TRT (1 TG)

6. Necessity of Generator protections
Generator winding insulation failure due to:
1. over voltage due to switching
2. over voltage due to the direct and indirect lightning strokes
3. Bridging of conductors by birds
4. Breakdown of insulation due to decrease of its dielectric
strength
5. Mechanical damage to the equipment

7. Basic requirements of protective relaying
A well designed and efficient protective relaying should
have:
1. Speed
2. Selectivity
3. Sensitivity
4. Reliability
5. Simplicity
6. Economy

8. Types of protections: -
Two types of protection:
1. Primary protection
2. Backup protection

9. Classification of relays:-
 Ordinary electromagnetic relays
 Electromagnetic induction or simply induction relays
 Electro thermal relays
 Physic electric relays
 Static-relays
 Electro-dynamic relays

10. Relays may also be classified depending upon
their application:
 Under-voltage, under-current, and under-power relays
 Over voltage over current and over power relays
 Directional or reverse current relays
 Directional or reverse power relays
 Differential relays
 Distance relays
 Static relays
 Microprocessor relays

11. Study of protections provided in generator
 Protection of the stator winding:
 Phase to phase faults.
 Phase to earth faults.
 Short circuit between turns.
 Open circuit in winding.
 Overheating due to inadequate cooling

12. Relays classified according to time of
operation:
 Instantaneous relays
 Definite time lag relay
 Inverse time lag relays
 Inverse definite minimum time relays