V Ramakrishna Central Electricit A thoritV Ramakrishna, Central Electricity Authority

Subir Sen, Power Grid Corpn. of India Ltd.

Presentation Flow

Overview of Indian Power System

F t d d l i Future demand-supply scenario

Consideration for high capacity 1200kV transmission corridor Consideration for high capacity 1200kV transmission corridordevelopment

Broad 1200kV AC technical parameters

1200kV UHVAC Test Station

Summary Summary

Indian Power System - Present

Installed Capacity: 147GW

Peak Demand : 109 GW

Transmission Grid Comprises: 765kV Lines - 1600 ckt. km

400kV Li 76 000 kt kNER

NR

400kV Lines - 76,000 ckt. km

220/132kV Lines - 115,000 ckt. km

HVDC bipoles - 3 nos.ER

HVDC back-to-back - 7 nos.

FSC – 18 nos.

TCSC – 6 nos.

WR

NER, ER, NR & WR operating as single grid of 100 GW

SR Grid – 40 GWSR AN

DAM

NIC

O

LAKSHA

Inter-regional capacity : 18,700 MW

MAN

&

OBAR

ADWEEP

National Grid - At Present

Eastern RegionNorthern

Region

North-easternRegion1260 MW g

6330 MW 1260 MW

2120 MW

Western Region

2990MW2990MW

3630 MW 1720 MW

Southern Region

Inter-regional Capacity - 18,700MW (incl. 132kV links)

NATIONAL GRID-EXISTINGInter-regional capacity : 18,700MW

NR

Inter-Regional Capacity-18700 MW

,

KOTA

AURAIYA

AGRA

GORAKHPUR

BALIA

PURISAHU

SALAKATI

MUZAFFARPUR

PATNABARH

BIHARSHARIFF

BIRPARA NERBONGAIGAON

M'SARAI/A'BAD

UJJAIN

WR

GWALIOR

RAIPUR

VINDHYACHALKORBA

MALANPUR

PURI500MW

ERBUDHIPADAR

ROURKELATALCHER

DEHRI

SASARAMMALDA

RANCHISIPAT

BALIMELA

KOLHAPUR

PONDA

CHANDRAPUR

U SILERU

1000MW

GAZUWAKA

MW1000

SRNAGJHARI

BELGAUMU.SILERU

National Grid by 2012

EasternNorthern N h

6000 MW

Eastern Region

Northern Region North-

easternRegion12130 MW 2860 MW

Western

4220 MW

Region6490 MW

3630 MW2720 MW

Southern Region

3630 MW 2720 MW

Inter-regional Capacity - 38,700MW (incl. 132kV links)

National Grid by 2012

N R

Inter-regional capacity : 38,700 MW

G O R A K H P U R

A G R A

K A N K R O LIR A PP

K O TA

A U R A IY A

FA TE H P U R

N R

B IR P A R AS IL IG U R I

B A LIAM U ZA FFA R P U R

P A TN AB A R H

N ERB O N G A IG A O N

S A LA K A TI

V IN D H Y A C H A L

W R P O O LIN GG W A LIO RU JJA IN

N A G D AZE R D A

M A LA N P U R

K O TA

ERM A LD A

S IL IG U R I

N A G A RP U R I

S IP A T

K O R B A

R O U R K ELAR A N C H I

D E H R I

S A H U

B A R HB 'S H A R IFFN A B I

B O N G A IG A O N

500M W

B U D H IP A D A R

S A S A R A MG A YA

C H A N D R A P U R

K O LH A P U R

P O N D A1000M W

M W1000

G A ZU W A K A

R A IP U RW RB A LIM ELA

R O U R K ELATA LC H E R

1000M W

U .S ILER U

N A G JH A R I

SR

B E LG A U M

G A ZU W A K A

N A R E N D R A

National Grid – A Continuing Process

Growth of Installed Capacity/Demand700

600Insta lled C apac ity

400

500D em and(P eak)In te r R eg iona l C apac ity

300

400

GW

200

0

100

2007 2012 2022Y ear

Energy Resource Map

• Hydro potential in NERand upper part of NR

• Coal reserves mainly in ER

• Ensure optimal utilisation of resources – strong National Grid is in placeNational Grid is in place and capacity is being enhanced continuously

Likely Capacity addition in next 15 years Peak Demand : 450GW Peak Demand : 450GW

Inst. Capacity : 600GW

Additional capacity addition of about 390GW would be required

Distributed 50 Hydro 80

Coastal, 90

Coal, 80

Nuclear, 90Load centre based, 90

Future Demand-Supply Scenario

Region Installed Capacity

(GW)

Availability (GW)

Peak Demand

(GW)

Surplus(+) /Deficit (-)

GW(GW) (GW) GWNorthern 145 110 140 (-) 30

Western 135 100 130 ( ) 30Western 135 100 130 (- ) 30

Southern 135 100 130 (- ) 30

Eastern 105 80 40 (+) 40

North-eastern

80 60 10 (+) 50

Total 600 450 450Total 600 450 450

Likely power transfer requirement between various regions in next 15 years

North-eastern Region

Northern Region27 GW

18 GW

IC = 145 GW IC = 80 GW

10,000MW

Despatch = 110 GWDemand = 140 GW

Deficit = 30 GWEastern Region

Despatch = 60 GWDemand = 10 GWSurplus = 50 GW

20 GW

,

23 GWWestern Region

IC = 135 GWDespatch = 100 GW

IC = 106 GWDespatch = 80 GWDemand = 40 GWSurplus = 40 GW ALL INDIA

IC = 600 GWD d 450 GW

15 GW15 GW

Demand = 130 GWDeficit = 30 GW

Demand = 450 GW

Southern RegionIC = 135 GW

Despatch = 100 GWDemand = 130 GW

Deficit = 30,GW

Power Transfer Requirement by 2014-153,000MWJharkhand-8000MW

NERNR12,500MW

ER3,000MW

4,000MWIC = 74,000MW

Demand = 56,500MW IC = 6,300MW

1,000MW

Deficit = -19,000MW Demand = 3,000MWSurplus = 2,500MW

IC = 63,000MWDemand = 23,000MWSurplus = 18 000MW

5,000MW

WR

1,000MW

17,000MW

IC = 85 000MW

Surplus = 18,000MW

Monet:900MWJindal:1320MW

Sterlite:2400MW

1 000MW

WR

2 500MW10,000MW

IC = 85,000MWDemand = 55,000MW

Deficit = -6,000MW

Malaxmi:956MWVisa:500 MWKVK:560MWLanco:693MW

Orissa-7330MW

1,000MW1,000MW

SR

Existing/Planned

Being Planned

2,500MW1,000MW

IC = 68,000MWDemand = 49 000MW

4,000MWChattishgarh:8000MW

S Demand = 49,000MWSurplus = 6,000MW

A.P. : 12000MWTamil Nadu : 7000MW

Consideration for Future Transmission Development

1. Requirement of Bulk power transfer over Long Distances from resources rich area/region to load centersg

2. ROW constraints, limited Transmission corridors available

3. High Short Circuit Levels

4. Variation and regulation in Power Flow

Power Flow Pattern

1. Variation in generation High hydro in monsoon and summer In winter only during peak hours Power flow variations due to commercial/operational

reasons

2. Variation in load demand Daily basis (peak and off-peak) Seasonal variations

Due to above, each transmission corridor has varied fl tt i f hi h t l l dipower flow pattern ranging from high to low loading, results into wide variation in voltages

Present Technologies & its Limitations

400 kV Twin Moose - upto 600-700MW

400 kV Quad Moose - Upto 1200-1500MW 400 kV Quad Moose Upto 1200 1500MW

765 kV Line - upto 2000/3000 MW

• Sipat – Seoni first 765 kV line operated at rated voltage

HVDC bipole - + 500 kV upto 2000-2500MW

Need

1. Development of hybrid transmission system for maintaining critical parameters as well as regulations of power flow

2. Increase in MW flow per metre of ROW

3. Controlling high Short Circuit Levels

Transmission System through Narrow Area

Eastern Region/ Western Region/

North-eastern Region

Requirement of Power Flow between NER & ER/WR/NR: 50 GW

Southern RegionRegion

50 GW

Requirement of Power Flow between NER & ER/WR/NR: 50 GWRequired Transmission Capacity : 57.5 GW (15% redundancy) Existing & planned Capacity : 9.5 GWAdditional Trans. Capacity to be planned : 48 GW

Options : 1. +800kV HVDC : 8nos.2. +800kV HVDC : 5nos.; 765kV EHVAC : 6nos.3. +800kV HVDC : 4nos.; 1200kV UHVAC : 2nos.

Selection of Next Level Transmission Voltage i.e. 1200kV UHVAC in view of : Loading lines upto Thermal Capacity(10000 MW) compared to SIL(6000 MW) Loading lines upto Thermal Capacity(10000 MW) compared to SIL(6000 MW) Saving Right of Way

EVACUATION OF 50,000MW THROUGH

Transmission System through Narrow Area,

CHICKEN NECK AREAFrom

NER1200KV UHVAC

MW

CHICKEN NECK AREA

MynmarBhutan

SikkimNER

1200KV UHVAC120

5000 MW

5000 MW

W800KV HVDC

locationsTo differentMynma

800KV HVDC

6000 MW

800KV HVDC

6000 MW

6000 MW800KV

locin

WesternNorthern,

800KV HVDC

6000 MW

800KV HVDC

6000 MW

6000

Upto 2012

Eastern

Wand

Region

400KV EHVAC

400KV EHVAC

2000 MW

2000 MW

1200kV AC Transmission System – Considerations

In Chhattisgarh State, projects with total capacity of about35,000 MW have been planned to be commissionedprogressively in the next 4-5 years.progressively in the next 4 5 years.

Power from these projects is to be transferred to bulk loadcentres in the Western and Northern Regions.

T f ili h f h f To facilitate exchange of such quantum of power,strengthening of East-West and East-North transmissioncorridors in WR is required.q

Further, it has been observed that growth of interconnection atk / k l l ld l i i i h i i400kV/765kV level would result into increase in short circuit

level at various EHV substations beyond the limit (40kA)

1200kV AC Transmission System – A Case Study

Considering quantum of power transfer on long-term as well as toaddress high short circuit level, a high capacity 1200kV transmissioncorridor i.e, Raipur-Wardha and Wardha- Aurangabad is proposedcorridor i.e, Raipur Wardha and Wardha Aurangabad is proposed

Projects are being developed in a phased manner with less powertransfer requirement initially, it is proposed that this high capacityEast-West transmission corridor shall be operated initially at 400kVlevellevel.Accordingly, with suitable design 1200kV S/c line is initiallyproposed to be operated as a 400kV (quad) D/c line so that systemredundancy can be maintained.Subsequently, with the increase in power transfer requirementthrough this corridor line shall be operated at 1200kV levelthrough this corridor, line shall be operated at 1200kV level

Proposed 1200kV AC Transmission Corridor

Line Parameters

Line parameters of 1200kV/765kV/400kV Transmission System

1200 kV 765kV 400kV

Nominal Voltage (kV) 1150 765 400

Highest voltage(kV) 1200 800 420

Resistance (pu/km) 4.338 x10-7 1.951x10-6 1.862x10-5

Reactance (pu/km) 1.772 x10-5 4.475x10-5 2.075x10-4

Susceptance (pu/km) 6.447 x10-2 2.4x10-2 5.55x10-3

Surge Impedance Loading (MW)

6030 2315 515

Base kV :1200kV/765kV/400kV; Base MVA :100 MVA

Large Variation of Reactive MVAR

R f 1200kV AC li i 1/3 d f 765kVReactance of 1200kV AC line is 1/3rd of 765kV system

Susceptance (charging capacitance) is 2½ times more of765kV line

Wide difference in the electrical parameters shall lead to theproblems of reactive power (VAR) balance

Huge Reactive Power Generation by 1200kV line about 6MVAR/km

These uncompensated lines shall generate huge capacitivecharging reactive power for which static reactive compensationdevices like shunt reactor, bus reactor of adequate size is to beprovided

1200kV Wardha – Aurangabad line reactive power characteristic

3000

1000

2000

AR

)

0

1000

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000Flow

( M

VA

-1000

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000

Power Flow (MW)

Rec

ativ

e

-3000

-2000

Reactive Power Management of 1200kV LinesReactive Power Management of 1200kV Lines

Maintaining constant/optimum level of power flow on the 1200kV AC system under different operating conditionsT l h h 1200kV AC l d f To control power through 1200kV AC system a layered system of 1200kV AC transmission corridor along with 800kV, 6000MW HVDC system shall be developedHVDC system shall be developed

Control and regulation mechanisms Exchange of power between 1200kV AC system and lower g p y

level network (765kV/400kV) through HVDC back-to back links at strategic locations

Control of power flow on the 800kV HVDC bipole lines

Dynamic Reactive Power Management through Series and Shunt Dynamic Reactive Power Management through Series and Shunt Compensation

Maintaining Uniform power flow through 1200kV System

Layered high capacity transmission network with control & regulation features

1200kV UHVAC System

800kV HVDC800kV HVDC

765kV EHVAC System

400kV EHVAC System

500kV HVDC500kV HVDC

~220kV/132kV SYSTEM

Increase in Short Circuit Level

Indian system is designed for max. short circuit level – 40kA

After 30 years of operation it is expected that fault level at After 30 years of operation, it is expected that fault level atvarious S/s shall increase beyond its limit in next 4-5 years

Most of these s/s are either major pooling stations or highcapacity trans. Interconnections with major generationp y j gcomplex/substations

Development of 1200kV transmission corridors shall facilitatein controlling high short circuit level, although other mitigatingmeasures are also being taken

Other 1200kV ParametersBased on the preliminary studies, broad parameters determined as under :

SlNo.

Description/Parameters Unit Value

Based on the preliminary studies, broad parameters determined as under :

1 System Nominal Operating parameters

(i) Phase – Phase kV 1150(ii) Frequency Hz 50

(iii) Number of phases Nos 32 System Maximum Voltage (Ph-Ph) kV 1200y g ( )3 System Insulation Levels

(i) Full wave impulse withstand voltage kV 2400(i) Full wave impulse withstand voltage(1.2/50 microsec.)

kV 2400

(ii) Switching impulse withstand voltage(250/2500 micro sec.) dry and wet

kV 1800( ) y

(iii) One minute power frequency dry and wetwithstand voltage (rms)

1200

Other 1200kV Parameters …contd

Sl No Description/Parameters Unit ValueSl No. Description/Parameters Unit Value

4 Short Circuit Level kA 505 Corona extinction voltage kV 762g6 Max. radio interference voltage for

frequency between 0.5 MHz and 2 MHzat 762 kV rms for 1200kV system

Micro V 1000

7 Creepage Distance mm/kV 25 i.e. (Total 30000 for1200kV system).

8 Bus Bars/Equipment Interconnections8 Bus Bars/Equipment Interconnections

(i) Tubular Bus/Connections Twin Al. 4” IPS tubes with450mm/550mm spacing.p g

(ii) Height m 18.00(iii) Strung Bus/Equipment Connections Octa Bundle Bersimis with(iii) Strung Bus/Equipment Connections

Conductor BundleOcta Bundle Bersimis with450 mm sub conductorspacing

Other 1200kV Parameters …contd

SlNo.

Description/Parameters Unit Value

9 Clearances

(i) Minimum Phase to Phase Clearance m 12.30

(ii) Minimum Phase to Earth Clearance m 8.30

(iii) Sectional clearances m 10.5

(iv) Phase to Phase distance (Pie Structure) m 27 00(iv) Phase to Phase distance (Pie Structure) m 27.00

10 System neutral earthing - Effectivelyearthed

Field Studies on 1200kV AC System

POWERGRID has undertaken various studies and tests todetermine the configuration of its 1200kV transmission lines,liklike

corona cage studies

air gap insulation studies

tests for voltage distribution on the insulator string

l t t di t t li f t f AN RIV & long term studies on test line for measurement of AN, RIV &

voltage gradient measurement at ground level

Establishment of 1200 kV AC Test Station

To develop 1200kV technology indigenously, POWERGRID

in collaboration with manufacturers establishing a 1200kVg

AC Test Station at Bina

This endeavour shall benefit the Indian Power sector and

manufacturers for

• Optimisation of transmission cost

• Ease in O&M• Ease in O&M

1200KV UHVAC Test Station

A 3 phase 1200kV Test Lines (S/C & D/C) of about 1 kmlength are being constructed. Salient features:

Variable Phase to Phase Spacings

Variable Ground Clearance

Upto 12 sub-conductor bundle

V i bl B dl di t Variable Bundle diameter

A 1200kV 3-phase test bay is being constructed to charge these A 1200kV 3-phase test bay is being constructed to charge theseTest Lines

1200KV UHVAC Test Station

Test station shall be fully equipped with testing instrumentfor field testingfor field testing

Extensive developmental tests shall be conducted on the testpline as well as on s/s equipments installed in the Test Bayjointly by Utilities, Manufacturer & Research Institute

Summary

To meet growing power transfer requirement and environmentalfriendly development, 1200kV AC system along with 800kV,6000MW HVDC system has been planned in the Indian Power6000MW HVDC system has been planned in the Indian PowerSystem

Reactive power management for 1200kV AC system is an Reactive power management for 1200kV AC system is animportant aspect which require detail analysis for suitable staticand dynamic reactive compensationand dynamic reactive compensation

Results of some of preliminary studies discussed

More studies and field tests are under process to finalise all the More studies and field tests are under process to finalise all thecritical electrical parameters

Establishment of a 1200kV AC Test Station at Bina is under Establishment of a 1200kV AC Test Station at Bina is underprogress

Thank YouTh k YThank YouThank You