V.K. AGRAWAL
Power System Operation
Corporation/NLDC, India vkagrawal@posoco.in
P.K. AGARWAL
Power System Operation
Corporation/NLDC, India pk.agarwal@posoco.in
HARISH RATHOUR
Power System Operation
Corporation/NLDC, India harishrathour@posoco.in
Presented by – P.K.Agarwal, AGM, POSOCO, pk.agarwal@posoco.in

• Indian Power System
• Wide Area Monitoring System
• Synchrophasors Pilot Projects.
• Challenges in Up-scaling to National Pilot Project.
• Way forward - URTDSM Scheme
14-11-2013 Experience of Upscaling to National Pilot
Project
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14-11-2013 Experience of Upscaling to National Pilot Project 3

Five Regional Grids
Five Frequencies
Pre
– October 1991
Evolution of National Grid
October 1991
East and Northeast synchronized
March 2003
West synchronized
With East & Northeast
August 2006
North synchronized
With Central Grid
Five Regional Grids
Two Frequencies
Post August 2006
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Future: 2014
One Grid - One Nation
One Frequency
Experience of Upscaling to National Pilot Project 4
4

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NORTHERN
REGION
WESTER
NREGIO
N
Indian Grid Diversity
Deficit Region
Snow fed – run-of –the –river hydro
REGIONAL
Adverse weather conditions: Fog & Dust
GRIDS Storm
Very low load
High hydro potential
Evacuation problems
EASTERN
REGION
NORTH-
EASTERN
REGION
Low load
High coal reserves
Pit head base load plants
Industrial load and agricultural load
High load (40% agricultural load)
Monsoon dependent hydro
SOUTHERN
REGION
ALL INDIA INSTALLED CAPACITY
NORTH
EAST
SOUTH
WEST
:-
:-
:-
:-
NORTH-EAST :-
TOTAL :- 228 GW
61.3 GW
28.8 GW
56.8 GW
78.7 GW
2.9 GW
Experience of Upscaling to National Pilot Project 5

Maps not to scale
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Nepal Bhutan
Over 16 links of 132/33/11 KV
Radial links with Nepal
Net import by Nepal
Tala: 1020 MW
Chukha: 336 MW
Kurichu: 60 MW
Net import by India
Bangladesh
400 KV AC line between
Baharampur(India) and
Bheramara(Bangladesh) with 500 MW
HVDC sub-station at Bheramara
Sri Lanka
Proposed Madurai (India) and
Anuradhapura (Sri-Lanka) through
± 500 KV HVDC under sea cable
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• WAMS is a networks of Phasor Measurement Units consist of
– PMUs synchronised with GPS.
– Fast communication channels like FO.
– Phasor data concentrator.
– Data management and services software.
PMU
PMU
Data Storage and
Applications
Data Storage and
Applications
PDC Input
Streams
PDC
PDC
Output
Streams
Regional
PDC
PDC
Output
Streams
National
PDC
PMU
A Typical Architecture of WAMS
14-11-2013 Experience of Upscaling to National Pilot Project 8

• Allows us to see dynamics not visible in traditional SCADA measurement.
• Enables accurate event analysis by precise comparison
• Like traffic cameras monitoring transmission highways.
• Visualize traffic density as well as pattern.
• Improve situational awareness.
• Provide early warning of subtlest beginning of dynamic interaction.
• Provides root cause analysis of the events.
14-11-2013 Experience of Upscaling to National Pilot Project 9

SCADA/EMS WAMS Advantages Features
Data Periodicity
& Measurement
4-10 seconds
Unsynchronized
40 milisecond
Synchronized
Angle
Measurement
Not possible Possible
Accurate System representation for pin pointed problems detection
Improved Power Flow for maintaining automatic
Load/Generation balance
Oscillation
Monitoring
Post fault analysis
Dynamic behavior of the
System
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Not possible
Not in Real
Time
Not possible
Possible
Possible in
Real Time.
Possible
Power System Oscillations damping by improved tuning to achieve greater Grid
Stability
Accurate & Fast Fault Analysis for suitable remedial actions
Corrective measures possible to achieve greater Grid
Stability
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• First PLU Pilot Project in India was implemented in by Powergrid/POSOCO in
Northern Region.
• Project was having 1 PDC and 4 PMUs. Later more added. Now 14 Nos. in NR.
Time Line:
Dates
June 2009
Sep 2009
Oct 2009
Dec 2009
Jan 2010
May 2010
Milestones
Management approval
Floating of Tender
Vetting of technical specification
Approval by CERC
Award of Contract
Commissioning
Concept to Commissioning : Within one Year
PMU Locations: a) Separated by geographical distance large b) Monitoring the Network
Stability c) Near big generating stations / critical nodes d) Broad band communication link with the control centre e) Relative Importance from present topology and prospective augmentation
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1. Phasor Data Concentrator
2. Data Historian
3. LAN equipments
4. Operator Console.
1. Global Positioning System
2. Phasor Measurement Unit.
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Displays available at the operator console for visualization
Display for absolute frequency
Display for frequency difference
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Other Pilot projects being undertaken by other RLDCs
SN Northern Region
All PMU Locations
Southern
Region
Western Region
1
2
3
4
5
Agra
Bassi
Dadri HVDC
Hissar
Kanpur
Gajuwaka
Gooty
Kolar
Narendra
Ramagundam
Asoj
Bhadravati
Bina (MP)
Boisar
Dehgam
6
7
8
9
10
11
12
13
Moga Somanhalli Itarsi
HVDC Vindhychal, Sriperumbdur Jabalpur
Kishenpur
Meerut
Thrissur
Tirunelveli
Kalwa
Korba
Balia
Rihand
Bawana
Karcham Wangtoo
HEP
Vijaywada Raipur
Rgppl
Satna
Solapur
14 Mahendragarh Vindhyachal (WR)
15 Mundra APL
Eastern
Region
North Eastern
Region
Biharsharif f
Binaguri Badarpur
Durgapur Balipara
Farakka
Jamshedp
Agratala
Bongoigaon
Imphal ur
Jeypore
Patna
Ranchi
Rengali
Misa
Nehu
Sarusajai
Rourkela
Sasaram
Talcher
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Total no of PMUs - 59 Nos.
(including 3 nos. PMU installed by IPPs)
Region wise PMUs:
NR - 14 Nos
WR - 15 Nos
ER - 12 Nos
SR - 10 Nos
NER – 08 Nos
At present data from 44 PMUs are available at NLDC PDC.
In addition to above data from
4 PMUs installed as demo project is also available
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NLDC
Console
PDC
Historian
Router
PDC/Console
NR
14 PMUs
PDC/Console
PDC/Console PDC/Console
10 PMUs
SR
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12 PMUs
ER
15 PMUs
WR
Experience of Upscaling to National Pilot Project
PDC/Console
NER
8 PMUs
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• Non-availability of communication links/channels:
• PMU locations and regional control centers.
• Regional control centers to National
Control center.
• Location of some of the PMUs have to be shifted.
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• Some places due to limitation of cable length of GPS antenna.
• Due to unavailability of clearest possible view of the sky.
• GPS sometimes goes ‘out of sync’ in bad weather conditions.
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• PMUs needs accurate measurement of current and voltage signals as input
• Ideally input should be provided from protection core of the current transformer (CT).
• Non-availability of protection core or restriction of burden on protection core.
• Inputs to PMUs have to be provided from CT’s metering core.
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• Issue of providing CT/PT connections to PMUs came up.
• physical connection from CT/PT are available only in bay control units (BCU) installed in switch yard area.
• PMU requires main input from bus PT, they were installed in BCU having bus signals.
• CTs for feeders were available in different BCUs.
Hence, at such places line current could not be wired to PMUs.
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• Mismatch between different types of connectors used for termination of communication cables.
• different types of connectors-due to difference of rating/resistance/make and communication equipment of different technologies was a tedious task to resolve.
• Present communication system was installed under ULDC scheme in year 2000 - PDH technology - channels are separated by using hardware which uses G703 interface.
• Present equipment used for networking system uses Ethernet interface.
• Converters from G.703 to Ethernet were used.
• These converters require external power supply.
• became a week point due to need of external power supply..
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• Storage at Regional PDC vs at National PDC.
• National project, number of PMUs were large, increased data storage capacity have to be provided.
• Using of internal hard drives of servers for data storage was not feasible.
• storage area network (SAN) system has been used for providing the high capacity of hard disk capacity required for the data historian.
• SAN also provided the scalability of storage capacity required in future.
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• Parameters matching of regional PDC with that of national PDC were the tedious task.
• Regional PDCs are of different make, they were having OEM supplied configuration utilities
• matching of their configuration parameters were not straight forward task.
• open source PMU connection tester was used for establishing the communication availability than parameters were easy to match.
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Unified Real Time Dynamic State Measurement
(URTDSM) Project
PROJECT ENVISAGES:
• Installation of around 1750 PMU’s throughout the Grid in 2 phases at:
– All 400 kV stations in State and ISTS grids
– All generating stations at 220 kV and above
– HVDC terminals and inter-regional and inter-national tie lines
– Both ends of 400kV and above transmission lines at State and ISTS sector
• 32 PDCs located at SLDCs, RLDCs and NLDCs.
• Transmission of PMU data over fiber optic communication network
• Development of software analytics
• 30% of the PMUs to be supplied to be manufactured indigenously.
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URTDSM System – Data Flow Hierarchy
Super PDC at NLDC
Super PDC at Back up NLDC
Remote Consoles to share data for planning &
Research
Super PDCs at five RLDCs
Master PDCs at SLDCs
Router Router
Router
PMU -
1
PMUn
PMUs located at State
Sector Substations
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PMU -
1
PMUn
PMUs located at IPPs across the Grid
PMU -
1
PMUn
PMUs located at Central
Sector Substations
Experience of Upscaling to National Pilot Project 30

Real time
State monitoring
Online Vulnerability
Analysis of Distance Relays
Validation of network parameters
Online Instrument
Transformer validation
Model Validation
Synchrophasor based
State Estimation
PMU supervised tripping of Zone-3
Voltage
Stability Assessment
Frequency Stability assessment and control
Angular stability assessment and control
Validate and improve accuracy
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Necessary
Experience of Upscaling to National Pilot Project
Post-mortem analysis
Additional benefits
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Project
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