Smart Grid

Smart Grid Vision: Vision for a Holistic Power Supply and Delivery Chain

Stephen Lee Senior Technical Executive Power Delivery & Utilization November 2008

Smart Grid Two Way Communications….Sensors…….Intelligence Hype 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.

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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 Communication Wide Area Control Dynamic Power Plant Models

M ZIP

Dynamic Load Models

Monitoring, Modeling, Analysis, Coordination & Control © 2008 Electric Power Research Institute, Inc. All rights reserved.

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Most Needed Capabilities Requiring Research

Chain Integration

End-to-End Outage Management Dispatch

Dynamic Models

Restoration SCADA

Protection

Security Network Management Data Management

Alarm Management

© 2008 Electric Power Research Institute, Inc. All rights reserved.

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• Hierarchical Integration of Entire Supply & Delivery Chain • Optimal End-to-End Dispatch under Uncertainties • Dynamic Models of Generators and Loads • Online Alarm RootCause Diagnostics • Prevention of Cascading Outages, Safety Nets • Fast System Restoration After Blackouts

MW

Tehachapi, California Wind Generation in April – 2005 Could you predict the energy production for this wind park either day-ahead or 5 hours in advance?

700 600

Each Day is a different color. −Day 29

500

−Day 9

400 −Day 5

300

−Day 26

200

−Average

100

0 1

2

3

4

5

6

Source: California ISO © 2008 Electric Power Research Institute, Inc. All rights reserved.

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8

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hour 5

Methods of Coping with Wind Uncertainty

300

1-min MW

250

fcst 1

200

fcst 2 fcst 3

150 100 50 0

CAES

Sep07 02:24

Sep07 00:00

Sep06 21:36

Sep06 19:12

Sep06 16:48

6

350

Sep06 14:24

© 2008 Electric Power Research Institute, Inc. All rights reserved.

Potential wind curtailment

Sep06 12:00

• Short-Term – Better wind forecasting – Carry more operating and spinning reserve to handle up and down ramps of wind output – Rapid coordination with demand response and energy storage • Long-Term – Build more energy storage, e.g., Compressed Air Energy Storage (CAES) – Controllable demand response – Holistic planning of transmission, generation and demand • Virtual Service Aggregator

Potential Role of the Virtual Service Aggregator Traditional Traditional Power Plants Power Plants

Renewable Renewable Resources Resources

Energy Energy Storage Storage

Transmission Transmission Grid Grid

Real RealRegional Regional Control ControlCenter Center

End EndUses Uses and and Distributed Distributed Resources Resources

Financial Settlement of Net Difference Virtual Virtual Service Service Aggregator Aggregator

SS

© 2008 Electric Power Research Institute, Inc. All rights reserved.

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Power Flow Financial Transaction

Alarm Management 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.

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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 © 2008 Electric Power Research Institute, Inc. All rights reserved.

 

1

Voltage (pu)

0.8

0.6 Measured Simulated H=0.3 Simulated H=0.03 Simulated H=0.05 Simulated H=0.1 Simulated H=0.2 Simulated H =0.5

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

9

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

•Operators need online decision support for restoration strategies

40

30

•How can automation be used to improve system restoration?

6 - 1996 WSCC

20

2 - 1965 NE 4 - 1982 WSCC

10

5 - 1996 WSCC

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.

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Prevention of Cascading Outages – Safety Nets • Application of SynchroPhasor Measurements for Controlled Separation, Load Shedding and Generation Rejection – Controlled separation is an effective last resort to mitigate severe cascading failures – Voltage Instability Load Shedding – Online risk monitoring of potential cascading outages

© 2008 Electric Power Research Institute, Inc. All rights reserved.

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Thank you

© 2008 Electric Power Research Institute, Inc. All rights reserved.

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