STUDY OF 220kv

NETWORK IN

VISAKHAPATNAM STEEL

PLANT

Miniproject Report Submitted by:

A.Vamsi Krishna (10135A0208)M.Bharat (09131A0270)

S.Uday Bhaskar Raju (09131A0293)P.M.Kalyan Reddy (09131A0288)

Steel Industry is both a basic and a core industry.

Percapita consumption of steel in india during 1970’s was very low.

A shore based Integrated Steel Plant at Vizag was inaugurated by Smt.Indira Gandhi on 17th april 1970.

INTRODUCTION TO VSP:

Power is supplied to VSP from APTRANSCO Switching station over two 220Kv lines on double circuit towers.

MAJOR SECTIONS OF D.N.W:

Main Receiving Station(M.R.S)Load Block Stepdown

Substation(L.B.S.S)Relays testing labaratory

POWER DISTRIBUTION IN VSP:

Power requirements of VSP is met through captive generation as well as supply from AP TRANSCO grid.

Captive capacity of 270MW is sufficient to meet all the plant needs.

Turbo Generators of VSP normally operate in parallel with state grid.

Average demand is of 221MW.

AVERAGE DEMAND OF MAJOR SHOPS:

EASTERN BUS 400 Kv

DC BACK TO BACK

SOUTHERN BUS 400 Kv

TO JAIPUR

(ORISSA)

TO VIJAYAWADA (NUNNA)

315MVA400/220 KvAUTO X’MER

220 Kv

TO BOMMURU TO PENDURTHI TOGAJUWAKA

MRS 220 Kv BUS 1

BUS 2

BUS 1

BUS 2

TPP 220 Kv

LBSS 1

LBSS 3 LBSS 4 LBSS 2

12.5 MVA220/33 Kv X’MER

TO CPRS

AL1 AL2

ML1ML2 ML3

BC

BC

T111/220kv

T211/220kv

T311/220kv

T511/220kv

T411/11/220kv

11 Kv

TG 260 MW

TG 360 MW

TG 467.5 MW

BPTG 17.5 MW

GETG 112 MW

BPTG 27.5 MW

GETG 212 MW

MRS

LBSS 5

GSB 2 GSB 3

POWER GRID

SUB STATION

APSEB SWITCHING STATION

VSP

- BREAKER

TG 160 MW

MAIN RECEIVING STATION:

DISTRIBUTION NETWORK:

EXTRA HIGH VOLTAGE DISTRIBUTION:

Plant is configured as five electrical Load Blocks and Step Down sub-stations.

LOAD BLOCK STEP-DOWN SUBSTATIONS:

The further distribution of power from MRS is shown simply in the below block diagram

Main receiving station

Load block stepdown substation

Load block distribution substation

HVLC HVMCC LCSS

LT LOADS HT LOADS

L.B.S.S receives power at 220kv and steps down to 33/11/6.6kv by transformers for further distribution of power in blocks to shops.Only at L.B.S.S 5(T.P.P) generator power (11kv) is stepped up to 220kv for power evacuation from generators through GSB. Power flow to/from grid depends on generator level.

L.B.D.S:Receives power at 11kv.

L.C.S.S:Receives power at 11kv.Steps down power to 440v through transformers.

HIGH VOLTAGE DISTRIBUTION (33/11/6.6Kv):

Two 220/33kv transformers installed at CPRS fed from MRS, feed power to township step-down station.The 33kv supply from the transformer at LBSS2 feeds SMS ladle furnace transformer.Power at 220kv is stepped down to11/6.6kv in HVLC located in each unit.

Power supply to essential category loads of various zones extended from TPP directly from GSB at 11kv.

MEDIUM VOLTAGE DISTRIBUTION (BELOW 650V):In each shop, to cater to medium and low voltage load, 11kv/415v LCSS are formed.The transformers are of standard rating 1600/1000/750/630/250kVA in plant and township areas.

LOW VOLTAGE DISTRIBUTION (250V & BELOW):It consists of power supply on single phase to

lighting equipment, domestic appliances etc.

HIGH VOLTAGE LOAD CENTRE:Whenever direct 6.6kv supply is not available,

11/6.6kv transformers are provided for feeding HV motor loads.

AUTO BUS TRANSFER:To provide uninterrupted power supply to all the equipments of the plant viz., conveyors, and loads, HT switch board should always be intact and ensure continuous power in case of power loss of any section due to failures of its incoming supply. The corresponding bus coupler should close automatically.

CONCLUSION

The very purpose of using the 220 kV network in VSP is to reduce the power loss in the transmission of electric power.

In addition to its own captive power plant, AP TRANSCO grid is also kept synchronized with its power system.