COMMUNICATION COMMUNICATION

REQUIREMENTS FOR SCADAREQUIREMENTS FOR SCADA

�� Communication media should have:Communication media should have:

* High Reliability* High Reliability

* High Availability* High Availability

* Rapid Response* Rapid Response

* Transparency* Transparency

* Economy* Economy

* Flexibility* Flexibility

* Maintainability* Maintainability

Modes of CommunicationModes of Communication

�� PLCCPLCC

�� Leased Telephone circuitsLeased Telephone circuits

�� Microwave CommunicationMicrowave Communication

�� Fibre Optics CommunicationFibre Optics Communication

�� Satellite CommunicationSatellite Communication

PLCCPLCC

�� High voltage lines themselves are used as communication High voltage lines themselves are used as communication links.links.

�� Carrier Frequency: 50Carrier Frequency: 50--300 KHz.300 KHz.

�� 3 channels are used generally:3 channels are used generally:

MainMain--Channel Channel -->>

speech channel speech channel –– 300 Hz to 2000 Hz300 Hz to 2000 Hz

TelemetringTelemetring-- 2000 Hz to 3400 Hz2000 Hz to 3400 Hz

ProtectionProtection--ChannelChannel--I I -->>

speech channel speech channel –– 300 Hz to 2000 Hz300 Hz to 2000 Hz

TeleprotectionTeleprotection-- 2000 Hz to 3400 Hz2000 Hz to 3400 Hz

ProtectionProtection--ChannelChannel--II (BackupII (Backup--Protection)Protection)-->>

speech channel speech channel –– 300 Hz to 2000 Hz300 Hz to 2000 Hz

TeleprotectionTeleprotection-- 2000 Hz to 3400 Hz2000 Hz to 3400 Hz

PLCCPLCCAdvantages:Advantages:

1.1. High reliabilityHigh reliability

2.2. All channels are available for dedicated use by All channels are available for dedicated use by

powerpower--utility aloneutility alone

Disadvantages:Disadvantages:

1.1. Cost of insulating communication equipment is highCost of insulating communication equipment is high

2.2. High noise level due to CoronaHigh noise level due to Corona

3.3. High speed dataHigh speed data--transfer not possible because of transfer not possible because of

Bandwidth limitations.Bandwidth limitations.

Microwave CommunicationMicrowave Communication

�� LineLine--ofof--sight communicationsight communication

�� Requires repeaters at 50Requires repeaters at 50--60 kms. Intervals60 kms. Intervals

�� Provides sufficient bandwidth to meet the needs of Provides sufficient bandwidth to meet the needs of power utilitypower utility

�� Higher availability than PLCC, availablity not affected by Higher availability than PLCC, availablity not affected by maintenance or faults on the power linesmaintenance or faults on the power lines

�� Suffers from multipathSuffers from multipath--fading effectfading effect

�� In India, WPC (wireless planning & coIn India, WPC (wireless planning & co--ordination) wing ordination) wing has assigned 2.3has assigned 2.3--2.5 GHz and 2.82.5 GHz and 2.8--5 GHz bands to power 5 GHz bands to power sector usage.sector usage.

Digital Microwave Systems

Leased Telephone CircuitsLeased Telephone Circuits

•Simple solution, no need to develop own dedicated communication facility by power utility

•Availability of this mode of communication at remotely located substations is the deciding factor

FiberFiber--Optic CommunicationOptic Communication�� FiberFiber--optic communication is a method of transmitting information fromoptic communication is a method of transmitting information from

one place to another by sending light through an optical fiber. one place to another by sending light through an optical fiber. The light The light

forms an electromagnetic carrier wave that is modulated to carryforms an electromagnetic carrier wave that is modulated to carry

informationinformation

• The process of communicating using fiber-optics involves the following basic steps:

Creating the optical signal using a transmitterRelaying the signal along the fiber, ensuring that the signal does not become too distorted or weak Receiving the optical signal and converting it into an electrical signal

Analog/DigitalInterface

Voltage toCurrent converter

LightSource

Source toFiber

Interface

Fiber toLight

Detector Interface

LightDetector

Current toVoltage

converter

Analog/DigitalInterface

OUTPUT

INPUT

Optical Fiber

Fiber Optic CommunicationFiber Optic Communication

�� Advantages:Advantages:The ability to carry much more information and deliver it wiThe ability to carry much more information and deliver it with greater fidelity th greater fidelity

than either copper wire or coaxial cable.than either copper wire or coaxial cable.

Fiber optic cable can support much higher data rates, and aFiber optic cable can support much higher data rates, and at greater distancest greater distances

The fiber is totally immune to virtually all kinds of interferenThe fiber is totally immune to virtually all kinds of interference, including ce, including

lightning, and will not conduct electricity. It can therefore colightning, and will not conduct electricity. It can therefore come in direct me in direct

contact with high voltage electrical equipment and power lines. contact with high voltage electrical equipment and power lines.

�� POWERGRID POWERGRID uses overhead fiber optic communication:uses overhead fiber optic communication:

OPGWOPGW (optical ground wire cable)(optical ground wire cable)

ADSSADSS (all dielectric self supporting cable)(all dielectric self supporting cable)

WRAP AROUNDWRAP AROUND

Fibre Optic Systems

OPGW

FODP OLTE

ADD DROP MUX2 MB/S

MICROWAVE RADIO TERMINAL

2 MB/S

INTEGRATION OF DIGITAL & ANALOGNETWORKS

PLCC

VOICE CARD

DATA CARD

OPGWOPGW

�� OPGW (optical ground wire) replaces OPGW (optical ground wire) replaces shield wiresshield wires

•• Provides lightning protectionProvides lightning protection

•• Provides communicationProvides communication

•• Lightning short circuit damageLightning short circuit damage

•• Installation requires long term outageInstallation requires long term outage

•• ExpensiveExpensive

•• Superior performanceSuperior performance

ADSS F.OADSS F.O

�� ADSS (all dielectric self supporting) whichADSS (all dielectric self supporting) which

is mounted at various locations, typically 3is mounted at various locations, typically 3

to 10 meters below the phase conductorsto 10 meters below the phase conductors..

�� ADSS costs less than OPGWADSS costs less than OPGW

�� Higher fiber count than Wrap type.Higher fiber count than Wrap type.

�� Can be installed on towers not designed Can be installed on towers not designed

for shield wires.for shield wires.

�� Suitable for hot line installationSuitable for hot line installation

WRAP AROUND F.OWRAP AROUND F.O

�� WrapWrap--type which is wound around type which is wound around shield wires and, in some instances, shield wires and, in some instances, around energized conductorsaround energized conductors

�� HotHot--line installation is difficultline installation is difficult

�� Cost more than ADSS, but less than Cost more than ADSS, but less than OPGWOPGW

�� Need a shield wireNeed a shield wire

�� No operation problem is observedNo operation problem is observed

OPGW

WRAP

ADSS

OVERHEAD CABLES FOR OVERHEAD CABLES FOR

POWER UTILITIESPOWER UTILITIES

OPGW ADSS WRAP AROUND

AL STRANDAL COATED STEEL STRAND

AL TUBE

XLPE SHEATH

POLYESTER TAPE

MOISTURE BLOCKING COMPOUND

AERIAL OPTICAL FIBRE CABLES

FIBRESTRENGTH MEMBERS

LOOSE TUBE

AD\AS\RKG\JP\FIBCROSS

FIBRE OPTIC CABLE INSTALLATION

OPGW

WRAP AROUND

ADSS

AD\AS\RKG\JP\FIBINST

SATELLITE COMMUNICATIONSATELLITE COMMUNICATION

�� A geostationary satellite is A geostationary satellite is

used as an active repeater.used as an active repeater.

�� Modulated signals are send Modulated signals are send

from earth VSATs in 6 GHz from earth VSATs in 6 GHz

band to the satellite.band to the satellite.

�� Signals are beamed back to Signals are beamed back to

earth in 4 GHz band.earth in 4 GHz band.

�� Roundtime propagation delay Roundtime propagation delay

of 540ms existsof 540ms exists

�� Communication is interrupted Communication is interrupted

during eclipses.during eclipses.

VIJAYAWADATALLAPALLI

GAJUWAKA

VIDYUTH SOUDHA

GOOTY

SALEM400

UDUMALPETTRICHUR NORTH

MADURAI

TRICHY

SRIPERUMBUDUR

NEYVELI

CHINAKAMPALLYDAVANAGERE

RAMAGUNDAM

PONDY

SOMANAHALLI

P

N

PALLOM

KAYANKULAM

RSCC (1)

CPCC (1)

SLDC (4)

SUB-LDC / SCC (14)

FIBRE OPTIC LINK 110/132kv FIBRE OPTIC LINK (220kv)FIBRE OPTIC LINK (400kv)FIBRE OPTIC LINK (SEB)

MICROWAVE LINK (35 links)

SATELLITE LINK (KEB)RTU LOCATIONS (201)

WARANGAL

PEDAPALLIDURSHED

JAMMIKUNTA

VTPS

VIZAG SWS

KAKINADA

BOMMUR

BHIMADOLE

N’SAGAR PH

SRISAILAM PH

SRISAILAM LBPHKURNOOL

SOMAYAJULAPALLI

MUDDANOOR RTPP

ANANTHAPUR

SHAPURNAGAR

GHANAPUR

CH.GUTTA

HYDERABAD 400

LEGEND LEGEND

CHALAKUDI

KALAMASSERY

VIAKKAM

KUNDRA PARIPALLI

TRIVANDRUM NORTHVYDYUTHI BHAVANAM

KOZHIKODE

KANNUR-B

MADURAI400

CHENNAI

CHIDAMBARA M

MYLADUTURAI

SALEM230

ERODE

SIVAGANGA

KARAIKUDI

THIRUMAYAMPUDUKOTTAI

THIRUVARURORTHANADU

KOVIL VENNI

ADANIKOTTAI

INGUR

PONGALORE

PANRUTI

VILLIANUR

SP.KOVIL

BANGALORE

KUMBALGODI

HUBLI

APSEB

RTU’S

82

TNEB

RTU’S

40

KSEB

RTU’S

30

KEB

RTU’S

22

PONDY

RTU’S

05

CENTRAL

SECTOR RTU’S

22

Lingasugur

WRLDC Borivalli Vav Haldarwa JambuvaGotriSLDC Asoj

Itarsi

IndoreSub-LDC

ItarsiV’chalKorba STPP

RaipurBhilai-400(SLDC)

Jabalpur-400

Asoj

WRTCC

Indore

Dhule

VindhyanchalChandrapurPhadge

Kal

wa

Tarapur 1&2

Itarsi-220

Bina-400 Bho

pal-4

00S

ub-L

DC

Sat

na-2

20

Kat

ni-2

20

Jaba

lpur

-220

SLDC-Jabalpur

Korba-West

Korba-East

Kalwa

Kawas

Rajgarh

Khandwa

Sipat

Raigarh

Bhatapara

Seoni

Bhilai-220

Vadodara POP

Gandhar

Kakrapar

Dehgam

Tarapur 3&4

Phadge

Bhadrawati

Satna

Bina

Gwalior

VapiBoiser

LEGENDSGreen - ULDC Wideband LinkBLUE - PDT Link

Black - PLCC Link

Main Data PLCC Channel

St. By Data PLCC Channel

Both Main and Std. By Data PLCC Channel

Haldarwa Jambuva Asoj

62 Nos. PLCC Equipment109 Nos. Wideband ULDC Eqpt

MPSEB Sector

CSEB Sector

CSEB Sector

GEB Sector

WR-SC&C Communication system

ILA-387

ILA-174

ILA-311

ILA-194ILA-362 ILA-702ILA-368

KR-13RaipurB’Vati

SEB’s Wideband Equipment and OFC

OPGWU/G – OFC

SLDC GOA

Leased Link

PondaMapusa

Sembatti

Madurai 400

Trichy 400

Paramakudi Samayapuram Madurai North

Kodayar PH2

MaduraiSub LDC

Karaikudi

Tanjore 230

S R PudurPariyar PH

Theni KayatharE

Sathur

TTPS

PodukottaC

Echengodu

Adanakottai

Peramballur

Kovilvenni

Pugalur

Thiruvarur

Tuticorin Auto

Trichy 230

Chennai Sub-LDC

(NLC TS-I)

Erode Sub-LDC(Erode)

Wideband Channel Routing for Madurai Sub-LDC

OrthonaduSivagangai

Existing RTU – 9 nos.

Existing RTU integrated

New RTUs – 13 nos.

PLCC Link

MW Link

ChalakudyT. NorthKozhikode -BKannur-B

Kalamassery

PallomKayamkulamKundraParipallyTrivendrumNorth

VidyuthiBhavanam

RSCC,Bangalore (Udumalpet)

Wideband Routing from Sub-LDC to SLDC,(Kalamassery)COMMUNICATION NETWORK FOR KERALA

MW Link

FO Link