1. WESTERN REGIONAL LOAD DESPATCH CENTER
SCADA - Communication
Abhimanyu Gartia
DY GENERAL Manager
WESTERN REGIONAL LOAD DESPATCH CENTER
MUMBAI

2. COMMUNICATION REQUIREMENTS FOR SCADA
Communication media should have:
* High Reliability
* High Availability
* Rapid Response
* Transparency
* Economy
* Flexibility
* Maintainability

3. Load Despatching Facilities in India
31 SLDCs, 5 RLDCs, 1+1 NLDC
Wideband speech and data communication
Common database in SLDC/RLDC
Load Despatching Facilities in India
New Delhi
Katwariasarai
NLDC Main
NLDC Backup
Kalcutta
Golf Course Road
PG FO Comn
VSAT Commn
10 Sec
WRLDC
NRLDC
SRLDC
ERLDC
NERLDC
2 Sec
SLDC AP
SLDC KAR
SLDC AS
SLDC TR
2 Sec
ULDC Commn
Sub LDC C
Sub LDC W
Sub LDC V
KPTCL ABB
10 Sec
RTU A
RTU A
RTU X
RTU C
RTU X

4. (Industrial IDS Rules)
Complete Solution
Firewall
MONITORING, REPORTING, DATA GATHERING AND DATA ARCHIVING FROM EVERY SECURITY SYSTEM COMPONENT
Industrial Defender Console
Corporate LAN
Internet
Router/Firewall
Industrial Defender Guard
PERIMETER
PROTECTION WS
Test/QA
Industrial Defender
HIDS/RHIDS
Remote
HMI
Industrial Defender NIDS
HOST SECURITY AND PERFORMANCE MONITORING
NETWORK SECURITY AND PERFORMANCE MONITORING
Performance=rendimiento, wydajność
DMS/SCADA
Other
Systems
Security Audit
System Design
Installation
Commissioning
Life Cycle Support
(Industrial IDS Rules)
Historian 4

5. Secure Access to Electrical Substations

6. POSSIBLE COMMUNICATION
Data on different Protocol
IEC
IEC
IEC 61850
Modbus
OPC server
IT interface
Scheduling
Data wear housing
Web interface
PMU interface

7. (Industrial IDS Rules)
Complete Solution
Firewall
MONITORING, REPORTING, DATA GATHERING AND DATA ARCHIVING FROM EVERY SECURITY SYSTEM COMPONENT
Industrial Defender Console
Corporate LAN
Internet
Router/Firewall
Industrial Defender Guard
PERIMETER
PROTECTION WS
Test/QA
Industrial Defender
HIDS/RHIDS
Remote
HMI
Industrial Defender NIDS
HOST SECURITY AND PERFORMANCE MONITORING
NETWORK SECURITY AND PERFORMANCE MONITORING
Performance=rendimiento, wydajność
DMS/SCADA
Other
Systems
Security Audit
System Design
Installation
Commissioning
Life Cycle Support
(Industrial IDS Rules)
Historian 7

8. Secure Access to Electrical Substations

9. Scan Cycles All the analog data are scanned every 10/12 seconds
Status information are reported by exception
All status information are scanned for integrity check every 10 minutes
The SOE datas are time stamped at 1 ms resolution
Time synchronisation is done every 10 minutes

10. Modes of Communication
PLCC
Leased Telephone circuits
Microwave Communication
Fibre Optics Communication
Satellite Communication

11. PLCC High voltage lines themselves are used as communication links.
Carrier Frequency: KHz.
3 channels are used generally:
Main-Channel ->
speech channel – 300 Hz to 2000 Hz
Telemetring Hz to 3400 Hz
Protection-Channel-I ->
Teleprotection Hz to 3400 Hz
Protection-Channel-II (Backup-Protection)->

12. PLCC Advantages: High reliability
All channels are available for dedicated use by
power-utility alone
Disadvantages:
Cost of insulating communication equipment is high
High noise level due to Corona
High speed data-transfer not possible because of
Bandwidth limitations.

13. Applications of PLCC Voice Communication Fascimile Transmission
Tele-Protection
Tele-Metering

14. Types of Couplings
3 coupling schemes to couple voice, fax, tele-protection and tele-metering to the high-voltage transmission line:
Phase-to-Ground Coupling
Phase-to-Phase Coupling
Inter-Line Coupling

15. PHASE-TO-GROUND COUPLING
STATION-A
LMU ES LA DC CC WT
PLCC PANELS
STATION-B
PLCC PANELS
ES=Earth Switch DC=Drainage Coil WT=Wave Trap
LA=Lightening Arrester LMU=Line Matching Unit CC=Coupling capacitor

16. PHASE-TO-PHASE COUPLINGWT WT WT WT
STATION-B
STATION-A CC CC CC CC
LMU
LMU
LMU
LMU DC LA ES LA DC ES BT BT
PLCC PANELS
PLCC PANELS
ES=Earth Switch DC=Drainage Coil WT=Wave Trap
LA=Lightening Arrester LMU=Line Matching Unit CC=Coupling capacitor
BT=Balancing Transformer

17. INTER-LINE COUPLING STATION-B STATION-A BT BT WT WT CC CC CC CC LMUDC LA ES LA DC ES BT BT
PLCC PANELS
PLCC PANELS
ES=Earth Switch DC=Drainage Coil WT=Wave Trap
LA=Lightening Arrester LMU=Line Matching Unit CC=Coupling capacitor BT=Balancing Transformer

18. Microwave Communication
Line-of-sight communication
Requires repeaters at kms. Intervals
Provides sufficient bandwidth to meet the needs of power utility
Higher availability than PLCC, availablity not affected by maintenance or faults on the power lines
Suffers from multipath-fading effect
In India, WPC (wireless planning & co-ordination) wing has assigned GHz and GHz bands to power sector usage.

19. Digital Microwave Systems

20. Leased 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

21. Fiber-Optic Communication
Fiber-optic communication is a method of transmitting information from one place to another by sending light through an optical fiber. The light forms an electromagnetic carrier wave that is modulated to carry information
The process of communicating using fiber-optics involves the following basic
steps:
Creating the optical signal using a transmitter
Relaying 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
INPUT
Analog/Digital
Interface
Voltage to
Current
converter
Light
Source
Source to
Fiber
Interface
Optical Fiber
Current to
Voltage
converter
Analog/Digital
Interface
OUTPUT
Fiber to
Light
Detector
Interface
Light
Detector

22. Fiber Optic Communication
Advantages:
The ability to carry much more information and deliver it with greater fidelity than either copper wire or coaxial cable.
Fiber optic cable can support much higher data rates, and at greater distances
The fiber is totally immune to virtually all kinds of interference, including lightning, and will not conduct electricity. It can therefore come in direct contact with high voltage electrical equipment and power lines.
POWERGRID uses overhead fiber optic communication:
OPGW (optical ground wire cable)
ADSS (all dielectric self supporting cable)
WRAP AROUND

23. Fibre Optic Systems

24. INTEGRATION OF DIGITAL & ANALOG
NETWORKS
OPGW
PLCC
FODP
OLTE
VOICE
CARD
2 MB/S
ADD DROP MUX
DATA
CARD
2 MB/S
MICROWAVE RADIO TERMINAL

25. OPGW OPGW (optical ground wire) replaces shield wires
• Provides lightning protection
• Provides communication
• Lightning short circuit damage
• Installation requires long term outage
• Expensive
• Superior performance

26. ADSS F.O ADSS (all dielectric self supporting) which
is mounted at various locations, typically 3
to 10 meters below the phase conductors.
ADSS costs less than OPGW
Higher fiber count than Wrap type.
Can be installed on towers not designed for shield wires.
Suitable for hot line installation

27. WRAP AROUND F.O
Wrap-type which is wound around shield wires and, in some instances, around energized conductors
Hot-line installation is difficult
Cost more than ADSS, but less than OPGW
Need a shield wire
No operation problem is observed

28. OVERHEAD CABLES FOR POWER UTILITIES
OPGW
WRAP
ADSS

30. FIBRE OPTIC CABLE INSTALLATION
OPGW
WRAP AROUND
ADSS
AD\AS\RKG\JP\FIBINST

31. SATELLITE COMMUNICATION
A geostationary satellite is used as an active repeater.
Modulated signals are send from earth VSATs in 6 GHz band to the satellite.
Signals are beamed back to earth in 4 GHz band.
Roundtime propagation delay of 540ms exists
Communication is interrupted during eclipses.

32. Lingasugur

34. Wideband Channel Routing for Madurai Sub-LDC
Peramballur
Echengodu
Tanjore 230
Erode Sub-LDC
(Erode)
Chennai
Sub-LDC
(NLC TS-I)
Pugalur
Trichy 400
Trichy 230
Samayapuram
Madurai North
Paramakudi
Madurai
Sub LDC
Sivagangai
Karaikudi
Podukotta C
Adanakottai
Orthonadu
Kovilvenni
Thiruvarur
Madurai 400
Existing RTU – 9 nos.
Existing RTU integrated
New RTUs – 13 nos.
TTPS
Theni
Kayathar E
Kodayar PH2
Sembatti
Sathur
PLCC Link
MW Link
Pariyar PH
Tuticorin Auto
S R Pudur

35. WR-SC&C Communication system
SLDC
GOA
WR-SC&C Communication system
WRTCC
Asoj
GEB Sector
Gotri
SLDC
WRLDC
Haldarwa
Jambuva
Borivalli
Vav
Asoj
Kalwa
Kalwa
Mapusa
Vadodara
POP
Ponda
Tarapur 1&2
Haldarwa
Jambuva
Asoj
Tarapur 3&4
Kakrapar
Kawas
ILA-387
Phadge
Gandhar
Indore
Boiser
Vapi
Indore
Sub-LDC
LEGENDS
Bhopal-400
Sub-LDC
Green - ULDC Wideband Link
OPGW
ILA-174
BLUE - PDT Link
U/G – OFC
Dehgam
Bina-400
Leased Link
MPSEB Sector
Black - PLCC Link
Itarsi
Both Main and Std. By Data PLCC Channel
St. By Data PLCC Channel
Itarsi-220
Khandwa
Main Data PLCC Channel
62 Nos. PLCC Equipment
Rajgarh
109 Nos. Wideband ULDC Eqpt
Satna-220
SEB’s Wideband Equipment and OFC
ILA-311
Katni-220
Raigarh
CSEB Sector
Gwalior
Jabalpur-220
Seoni
Sipat
Korba-East
Bhadrawati
SLDC-
Jabalpur
Korba-West
Bina
CSEB Sector
Bhatapara
Satna
Bhilai-220
Jabalpur-400
Bhilai-400
(SLDC)
Korba
STPP
Raipur
ILA-362
ILA-194
V’chal
ILA-368
ILA-702
Itarsi
Dhule
Phadge
B’Vati
Raipur
KR-13
Vindhyanchal
Chandrapur

36. COMMUNICATION NETWORK FOR KERALA
Chalakudy
T. North
Kozhikode -B
Kannur-B
Kalamassery
Pallom
Kayamkulam
Kundra
Paripally
Trivendrum
North
Vidyuthi
Bhavanam
RSCC,Bangalore
(Udumalpet)
Wideband Routing from Sub-LDC to SLDC,(Kalamassery)
COMMUNICATION NETWORK FOR KERALA
MW Link
FO Link