Presentation on Vocational Training at DPLSubmitted by:

Inderveer Singh Kamboh

Dipanwita Ghosh

Satyajit Marik

Saumyadip Moitra

Sayantany Ghanty

Sumanta Das

Department of Electrical Engineering, BCREC

1BCREC/EE/7thSem

About DPL-Overview

Thermal Power Station

Alternator Units

Transformers

Transmission & Distribution

Protection Systems

Switch Yard

Load Dispatch centre

Coke Oven

Conclusion &Future prospects

2BCREC/EE/7thSem

About DPL-Overview

•Incorporated on 6th September,1961. Govt. of West Bengal Undertaking•Thermal Power Plant. A total of seven units of different capacities have an aggregate 701-mega watt of installed capacity •Consists of Coke Oven Batteries, Bye-products Plant, Gas Grid Project, Thermal Power Plant and Water Works•. Generation of power and its distribution at 11KV in its licensed area at Durgapur and transmission of surplus power to WBSEB & WBSEDCL

3BCREC/EE/7thSem

Thermal Power Station•A generating station, which converts heat energy of coal combustion into

electrical energy, is known as a steam power station

•A steam power station works on the Rankine cycle. Steam is produced in

the boiler by utilizing the heat of coal combustion that is then expanded in

the prime mover (i.e. steam turbine) and is condensed to be fed into the

boiler again. The steam turbine drives the alternator which converts

mechanically energy of turbine into electrical energy

ADVANTAGES:

The fuel (i.e. coal) used is quite cheap.

Less initial cost as compared to other generating stations

It can be installed at any place irrespective of the existence of coal. The

coal can be transported to the site of the plant by rail or road.

It requires less space as compared to the hydroelectric power stations.

4BCREC/EE/7thSem

Coal and ash handling arrangements.

Steam generating plant.

Steam turbine.

Boiler

Alternator.

Feed water.

Cooling arrangements

Layout of a typical Thermal Power Plant:

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BOILER:

•The boiler is a rectangular furnace about 50 feet (15 m) on a side and 130 feet (40 m) tall. Its walls are made of a web of high pressure steel tubes about 2.3 inches (58 mm) in diameter.•The accessories include –1.Economizer2. Boiler Drum3. Down comers 4. Water walls5. Water wall plates 6. Primary super heater 7. Platen super heater 8. Final Super heater 9. Reheater 10. Burner 11. Ignitors.•The heat of combustion of coal in the boiler is utilized to convert water into steam at high pressure and temperature.

6BCREC/EE/7thSem

•Generator of the alternator as it is usually called in the electrical end of the turbo-generator set. It is cylindrical pole synchronous generator•converts the mechanical energy of the turbine into electrical energy. The generation of electricity is based on the Faradays law of electromagnetic induction. •STATOR: THE stator is a component that embodies the armature core and armature winding.•ROTOR: The rotor forms the poles and provides the magnetic field. It revolves at a speed of 3000 r.p.m.

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Description Unit I Unit II Unit III Unit IV Unit V Unit VI Unit VII Total

Capacity(MW) 30 30 77 77 77 110 300 641

Date of

Synchronisation10.6.1960 10.4.1960 23.4.1964 19.6.1964 4.5.1966 3.7.1985 29.12.2007

Date of Commercial

Operation10.8.1960 10.6.1960 23.6.1964 29.6.1964 4.7.1966 1.1.1987 30.4.2008

Present Status Decommissioned Decommissioned In operation In operation In operation In operation In operation

Cross section of an elementarystator and salient-pole rotor

8BCREC/EE/7thSem

Transformer is the static device for rising or lowering voltage level in a.c. electrical circuitsIn DPPS there are 6 generator transformers., 1 auxiliary transformer & 1 reserve transformerThese transformers are cooled by three methods-OFAFONAFONAN BHEL is the provider for majority of these transformers.

9BCREC/EE/7thSem

Transformer Protection & Accessories:

There are many protection devices used to protect a power transformer. The factors governing the protection scheme are its size, importance and location of the transformer.CONSERVATORBREATHERBUCHHOLZ RELAYVENT PIPEAIR NATURAL COOLING FAN

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TRANSMISSION & DISTRIBUTION

The Power that is generated from power plant must be transmitted to different places through substations Every substations has one or more than one transformer & circuit breakers.132 KV Incomers Lightning arrester Isolator CT Circuit breaker Isolator Lightning arrester Step - transformer (132KV /11KV) 11 KV incomer Bus Bar Feeders Outgoing line Underground cable Distributor

11BCREC/EE/7thSem

Circuit Breakers:A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by overload or short circuit. Its basic function is to detect a fault condition and interrupt current flow.Type of circuit breaker:1)Low-voltage circuit breakers 2)Magnetic circuit breakers 3)Medium-voltage 4)High-voltage circuit breakers 5) (SF6) high-voltage circuit breakers6)Carbon dioxide (CO2) high-voltage CB 7)Vacuum circuit breakerRelayA relay is an electrically operated switch. Many relays use an electromagnet to mechanically operate a switch, but other operating principles are also used, such as solid-state relays

12BCREC/EE/7thSem

Isolator

ISOLATOR:•Isolator is basically a no load switch designed to operate under no load condition•Isolators used in power system are generally three pole isolators having identical supports•The isolators are “Horizontal Breaker Type”.LIGHTNING ARRESTER:

•Lightning Arrester are usually connected between phase and ground of the power plant to protect the equipment from sudden over voltages caused by lightning or some other reasons •Lightning arrester consists of low resistor and gap elements. Resistor elements consist of nonlinear resistors

13BCREC/EE/7thSem

In DPL there are three different KV bus bars present33KV132 KV220KV 33kv feeders go to two substation:-One is near Barrage at Bankura & another is near coal belt region.132kv feeders go to four substations of DPL. The substations are:-A-Substations(FCI)B-Substations(near MAMC)C-Substations(Durgapur Chemicals)C-1 Substations(near Raturia) 220kv feeders go to Bidhannagar substations

14BCREC/EE/7thSem

The Load Despatch Department is the nerve centre for the operation , planning , monitoring and control of the power system . Electricity cannot be stored and has to be produced when it is needed. It is therefore essential that power system is planned and operated optimally & economically.

DPLThere are 4 tie lines : 2 nos. of 132 KV line(temporarily OFF now) and 2 nos. of 220

KV line. These tie lines are used for import or export of power. Since now 132 KV lines are OFF hence at present the 2 nos. 220kV lines are used for this purpose.If there is excess power generation above demand then those excess are exported and if demand is more than generation then power has to be imported. These import and export of power is done from/ to WBSETCL and IEX(Indian energy Exchange).All consumers are of 132 KV, but power is generated or received at 220 KV. So to distribute power to the consumers there are 3 nos. auto transformer, 2 nos. 160 MVA 220Kv/ 132Kv transformers and 1 nos. 100 MVA transformer. These instruments step down power to 132 KV from 220 KV for distribution to consumers.It is also mandatory to buy some small amount of solar energy namely 2, 3, 4 MW.A 15 mins recording procedure is used for recording of power generation ,demand and frequency.

15BCREC/EE/7thSem

DPL's Coke Oven Complex is India's one of the largest Merchant Cokery producing Coke of global quality. The current installed capacity of the Coke Oven Complex is 0.5 million tonnes of Gross Coke per annum, 20,000 tonnes of Crude Coal Tar per annum and 90 million NM3 of Coke Oven gas per annum.

Description #1 #2 #3 #4 #5 Total

Nos of Ovens 30 30 - - 40 100

Status Operational Hot Blank Future

Rebuilding

Future

Rebuilding

Operational

Height (Mtrs) 4.5 4.5 - - 4.5

Width (mm) 400 400 - - 400

Length (mm) 13400 13400 - - 13430

Eff. Volume M3 21.74 21.74 - - 21.76

Type Twin flue Side jet gas gun

system

Twin flue Side jet gas gun

System

- - Twin flue underjet

heat regenerative

Oven Availability 100% 100% - - 100%

COKE OVEN

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Conclusion & Future Prospects:

•8th Unit 250 MW capacity is being built in association with BHEL•Units I &II decommissioned , sold as scrap.•In order to boost its financial position, DPL has forayed into Real Estate Sector.•Coal Bed Methane (CBM ) technology is being implemented for future power generation

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