Holistic Power Supply and
Delivery Chain –
Foundations for a Smart
Grid
Stephen Lee
Senior Technical Executive
Power Delivery & Utilization
March 10-11, 2009
Fifth Annual Carnegie Mellon Conference on the Electricity Industry
EPRI Report in Publication
• Presented and used in
Brainstorming session in
support of NASPI (North
America Synchro-Phasor
Initiative)
• Hosted by EPRI
• Charlotte
• October, 2008
• Major Building Blocks to turn
the Smart Grid from Hype to
Reality
© 2008 Electric Power Research Institute, Inc. All rights reserved.
2
Smart Grid: Hype Cycle
Smart
Grid
Need an Objective Assessment of the Potential for Smart Transmission and
the Path to Achieve it
© 2008 Electric Power Research Institute, Inc. All rights reserved.
3
Current State – System Operations
12
1
4
13
6
Limited Grid Visibility
14
5
2
15
7
8
17
16
9
3
11
10
2-4 Sec scan rates
Limited to info from lines and
transformers at substations
Credit to
•
Paul Myrda for animation of the dots
•
Steve Lee for the cloud
© 2008 Electric Power Research Institute, Inc. All rights reserved.
MW, MVAR, KV breaker status
4
Smart Transmission State – System
Operations
1
12
4
Enhanced Grid Visibility
750 +282j
440
+ 200j
750 + 262j
13
6
14
5
2
300 + 100j
250 +84j
15
176 +88j
7
8
17
100 +62j
16
130 + 8j
120 + 11j
20 + 8j
9
3
276 + 120j
350 + 150j
11
10
227 + 420j
Higher speed scan rates
704 + 308j
Allows more frequent analysis of
system state
Credit to Paul Myrda for animation of the dots
© 2008 Electric Power Research Institute, Inc. All rights reserved.
5
EPRI’s End-to-End Power Delivery Chain
Operation & Planning
Power Plants
Transmission System
Fuel Supply System
Distribution System
Renewable Plants
Fuel Source/Storage
Energy Storage
End-uses & DR
Controllers
Sensors
Data
Data Communication
Communication
Wide
Wide Area
Area Control
Control
Dynamic Power Plant Models
M
ZIP
Dynamic Load Models
Monitoring,
Monitoring, Modeling,
Modeling, Analysis,
Analysis, Coordination
Coordination &
& Control
Control
© 2008 Electric Power Research Institute, Inc. All rights reserved.
6
New Challenges for a Smart Grid
• Need to integrate:
– large-scale stochastic renewable generation
– electric energy storage
– distributed generation
– plug-in hybrid electric vehicles
– demand response (smart meters)
• Need to deploy and integrate:
– Synchronized measurement technologies
– Sensors
– System Integrity Protection Schemes (SIPS)
© 2008 Electric Power Research Institute, Inc. All rights reserved.
7
Foundations Still Deficient
• End-to-End Situational Awareness
• Alarm Management and Root-Cause
Diagnosis
• Dynamic Models of all Generators and
Loads
• Faster System Restoration
• System Integrity Protection Schemes
– Faster reflex actions on wide-area
problems
– Measurement-based safety nets to
prevent cascading blackouts, e.g., load
shedding, islanding/separation, damping
© 2008 Electric Power Research Institute, Inc. All rights reserved.
8
Alarm Management and Real-time Root-Cause
Diagnosis
Alarm Management
• Need to diagnose root-cause of
alarm messages
• Need to link diagnosis to operator
procedure
• Current EMS alarm management
uses technologies of the 1970s
• Need to integrate all sources of data
and messages, through a
hierarchical approach
© 2008 Electric Power Research Institute, Inc. All rights reserved.
9
Why Accurate Load and Generator Models Are
Needed?
Hassayampa 500 kV
• Inadequacy of current model data
– Inaccurate voltage recovery
simulation after disturbances
– Uncertainty about generator
reactive power capabilities
• Implications
– Uncertainty about the stability
margin of the power grid
– Unaware of real risk of
cascading blackouts or voltage
collapse, or
– Under utilization of available
stability margin for greater
economic benefits
1
Voltage (pu)
0.8
0.6
Measured
Simulated
Simulated
Simulated
Simulated
Simulated
Simulated
0.4
0.2
0
0
0.2
0.4
0.6
0.8
1
1.2
Time (seconds)
1.4
1.6
Southern Co.’s GenVARRTM
© 2008 Electric Power Research Institute, Inc. All rights reserved.
10
H=0.3
H=0.03
H=0.05
H=0.1
H=0.2
H =0.5
1.8
2
Effective System Restoration Can Reduce The
Societal Impact Of Widespread Blackouts
Major Power System Disturbances
70
1 - 2003 NE
60
Restoration Objectives:
Minimize Duration of Outages
Minimized Unserved Loads
Avoid Equipment Danage
Load Lost in GW
50
40
30
6 - 1996 W SCC
20
2 - 1965 NE
4 - 1982 W SCC
10
5 - 1996 W SCC
3 - 1977 NYC
7 - 1998 MW
0
0
10
20
30
40
50
60
Duration in Hours
Source: Mike Adibi, NSF/EPRI Workshop on Understanding and Preventing Cascading Failures in Power Systems, Oct 28, 2005.
© 2008 Electric Power Research Institute, Inc. All rights reserved.
11
New Solutions Are Needed
• Virtual Service Aggregators serving as Energy Balancing
Authorities
– Dispatch and control stochastic renewable generation
– Dispatch and control (and own?) large scale energy
storage plants
– Manage demand response proactively
– Manage smart electric vehicle charging
• Optimal end-to-end commitment and dispatch by
ISO/RTO as backstop for system reliability
• CO2 Cap-and-Trade Market Monitoring
© 2008 Electric Power Research Institute, Inc. All rights reserved.
12
Potential Role of the Virtual Service
Aggregator
Traditional
Traditional
Central
CentralStation
Station
Power Plants
Power Plants
Large-Scale
Large-Scale
Renewable
Renewable
Resources
Resources
Large-Scale
Large-Scale
Energy
Energy
Storage
Storage
Transmission
Transmission
Grid
Grid
Real
RealRegional
Regional
Control
ControlCenter
Center
Financial
Settlement of
Net Difference
Virtual
Virtual
Service
Service
Aggregator
Aggregator
S
© 2008 Electric Power Research Institute, Inc. All rights reserved.
13
Loads
Loads
End Uses
End Uses
and
and
Distributed
Distributed
Resources
Resources
Distributed
Distributed
Generation
Generation
&&Storage
Storage
Power Flow
Financial
Transaction
PHEVs
PHEVs
Conclusions
• Urgent Need to Make the Bulk Power System Really
Smart
• Failure to Make this a High Priority would Jeopardize the
Modernization of the Electric Power System
• Strengthening the Foundations is Indispensable
• Introducing New Solutions is critically needed
© 2008 Electric Power Research Institute, Inc. All rights reserved.
14
Discussions
© 2008 Electric Power Research Institute, Inc. All rights reserved.
15