Transcript Document

Breaking the Gridlock and
Averting Blackouts:
Key Technologies and Policy Recommendations
Massachusetts Restructuring Roundtable
Boston, MA
September 19, 2003
Breaking the Gridlock and Averting Blackouts:
Key Steps
• Recognize the role of the grid and the limits of DG.
Grid investment and innovation must be supported!
• Improved industry / policy understanding of the unique
(“reactive power”) requirements of AC Grids
• Near-term solution: dynamic reactive power equipment
(STATCOM, D-VAR, SuperVAR etc.)
• Longer-term: new approaches to control AC power
flows with controllable “VLI” superconductor cable
• “Islands and Bridges:” Should our grid be redesigned
with more DC transmission to reduce the threat of
blackouts from regional reactive power imbalances?
The Grid is Overstressed – and While Distributed
Generation Can Help, It Is Not “The” Solution!
• Increased demands on the same grid infrastructure
means, in effect, “too many cars – and not enough lanes”
• Distributed generation can actually compound the
reliability problem by raising fault current levels
• For DG’s role to expand, system-level issues must be
addressed (e.g., single fuel dependency, access to
remotely located renewable energy resources)
• “It’s tough to make predictions, especially about the
future.” (-- Yogi Berra)
• We don’t know what the future fuel mix will be – but we
can predict energy use will be electrified. Therefore the
grid must be robust enough to handle power flows under a
wide range of scenarios!
GDP Remains a Close Function of Power Use
1950
1975
2000
Data Sources:
kwh: Energy Info Administration
GDP: Federal Reserve Bank of St. Louis
We are becoming more energy-efficient -- yet more electricity-intensive!
What’s Needed: Public Policies to Support
Development of a 21st Century Grid That Is...
Smart…
Strong…
and Flexible
Reactive Power and Real Power:
Balance is Critical
This is reactive power.
This is real power!
Without reactive power, real power can’t get the work done!
Reactive Power and Real Power:
Balance is Critical
Too little – or too much – reactive power makes it impossible to apply real power
Low-Environmental-Impact Strategies to
Strengthen the Power Grid
• Dynamic Reactive Power Support -- “D-VAR” –
“Shock Absorbers” for the Power Grid
• SuperVAR Synchronous Condenser
• Controllable VLI (Very Low Impedance)
Superconductor Cable
• DC Transmission – a new vision of “Islands and
Bridges” to block the propagation of disturbances
across broad regions
D-VAR Technology Description
What are D-VAR Devices?
• Dynamic VARs… Fully Integrated Statcom with
proprietary 3X overload
• Instantaneously injects precise amounts of reactive
power into a network
• Optional real power with SMES energy storage
D-VAR mitigates wide variety of voltage and power quality related
transmission problems
Dynamic Reactive Power Support:
“Shock Absorbers” for the Power Grid
• Dynamic VAR (D-VARTM)
• Power Quality Industrial
Voltage Restorer (PQ-IVRTM)
• Distributed SMES (D-SMES)
Customized solutions for grid reliability and industrial power quality
Dynamic Reactive Power Support:
“Shock Absorbers” for the Power Grid
Wisconsin
Public Service
100 miles
200 MW Grid
A form of “distributed transmission” to boost grid reliability and power transfer
Typical D-VAR device
Highly Mobile… Scalable… Easy to Install... Self Contained…
Typical installation takes less than 1 week!
HTS Rotating Machines:
A Rapidly Developing Field
• 5,000 hp HTS Industrial Motor
• AMSC Self Funded Technical Development Project
• Built and Tested in 2000 – 2001
• 7,000 hp peak load, 5,900 hp steady state
• 5 MW HTS Propulsion Motor
• AMSC Navy Contract Awarded February 2002
• Delivered to U.S. Navy in July 2003
• 10X torque of 5,000 hp motor
• 36.5 MW HTS Propulsion Motor
• AMSC Navy Competitive Contract Award
February 2003
• Sized for DD(X) Class Warship Design
• All U.S. Team
• 13X Torque of 5 MW Motor
SuperVAR™ Synchronous Condenser:
Product Design Leverages Existing Technologies
•
Takes advantage of HTS Machine Technology
base already developed
• AMSC 5000HP motor project supports HTS
Coil Performance at 1800 rpm operating
speed
• 5 MW Navy Program Experience Supports
Torque Transfer and Exciter Design
•
Maximize Utilization of COTS (commercial offthe-shelf) components
• Stator – standard, air-cooled, iron core
stator
• Cooling components utilize MRI technology
• Commercially available journal bearings
and oil system
•
Designed for Manufacturability
SuperVAR Synchronous Condenser:
A New Grid Reliability Solution in Fall 2003
• Contract Awarded on
January 29, 2003.
• Factory Testing starts in
October 2003.
• TVA testing at Hoeganaes
Steel Plant near Nashville,
TN with a commissioning
date of November 12, 2003.
• TVA has ordered 5
commercial production units
rated 10 MVA at 13.8 kV for
delivery in 2005.
SuperVAR™ Synchronous Condenser:
Summary of Product Benefits
VARS ( Per Unit)
SuperVAR
• HTS SuperVARTM will deliver
100% of its rating in both lagging
and leading MVARS
Absorbing
VARS
Conventional
Machine
1
2
3
Field Current (Per Unit)
Fault Current (pu)
• Delivers up to 2 pu overload for
1 minute during a prolonged
voltage depression
Generating
VARS
1
• HTS SuperVAR will:
• Deliver 6.5x fault current for up
to first 5 cycles during a terminal
short-circuit
TM
10
7.577
5
0
10
5
i as
N
i ac
0
N
-5
-10
SuperVAR
Conventional
5
 5.81
10
0
0
0.02
0.04
0.06
0.08
tN
SuperVAR™ makes the synchronous condenser an outstanding grid reliability solution
Principal HTS Cable Designs -Single Phase vs. Coaxial Very Low Impedance
• All HTS Cables offer high power density advantages
• HTS Cable architectures vary according to purpose
Single Phase
•Single layer of HTS wire
•Retrofit installations -Urban distribution
•Low resistance & losses
•Inductance = conventional
•EMF = conventional
•Demonstrated to 115 kV
Coaxial VLI
•Two layers of HTS wire
•New installations -Urban & regional transmission
•Very low resistance
•Very low inductance
•Zero EMF; compact 3-in-1 design
•Demonstrated to 69 kV class
Comparison of Cable Technologies
345 kV
XLPE
230 kV
XLPE
HTS - VLI
XLPE
138 kV
HTS - VLI
XLPE
69 kV
HTS - VLI
XLPE
34.5 kV
0
25
75
50
100
150
200
300
400
500
600
700
800
900
Power Capacity (AC – 3ΦMVA)
Increase Capacity without the Need to Increase Operating Voltage
1000
Grid Impacts of VLI Cables
•
•
•
•
Significantly Lower Impedance Characteristics of HTS Cables Allow
Utilities to Redistribute Power Flows within a Networked System
Reduced reactive power losses provide more uniform voltage profile
across the transmission network
Effective electrical distances are significantly shortened
Total efficiency higher than Al or Cu based systems when operated at
high loads
A Comparison of Power Transmission Technologies – 120kV Class
Technology
Resistance
Inductance
Capacitance
(Ω/km)
(mH/km)
(nf/km)
Cold Dielectric HTS
0.0001
0.06
200
Conventional XLPE
0.03
0.36
257
Overhead
0.08
1.26
8.8
Up to 20x Less Impedance Compared to Overhead
HTS VLI Cable Solution to a DC Cable Project
Case: 138 kV cable
project from NJ power
plant to NYC to Long
Island is an alternate to
DC project
20 mile 138 kV
VLI Cable
800-900 MVA
To LIPA Load
Center - 10 Miles
To New
Jersey
Power Plant
Results:
• DC control obtained with
an AC VLI cable
• Multiple interconnect
points increased
flexibility
• Saves $200M on
converter stations and
real estate
Benefits of VLI Cable:
Financial & Economic, Environmental, Policy
Financial & Economic
• Lower voltages, shorter lengths because of controllability
• A new strategy for life extension / improved asset utilization of existing,
aging T&D systems
• Enhanced generator dispatch -- reduced regional grid congestion costs
Environmental
• Underground placement, shorter lengths, lower voltages and elimination
of EMF make for a “least environmental impact” transmission solution
Policy Implications
• More robust competition, improved reliability, enhanced air quality and
easier transmission siting
“Islands and Bridges”:
Should We Have More Interconnections?
NERC Regional
Interconnections
Smaller, Asynchronous Areas (Like Texas)
Might Isolate Disturbances More Effectively
WA
MT
ME
OR
ND
MN
NY
ID
WI
SD
WY
MI
IA
NE
RI
CT
PA
IL
NV
CA
KS
UT
WV
VA
KY
OK
NC
AZ
TN
AR
SC
MS
Note: Boundaries shown
are purely illustrative
(could match NERC
regions, RTO, state or
other natural boundaries)
AL
NJ
DE
MD
OH
IN
MO
CO
NM
VT
NH
GA
TX
LA
FL
MA
Market Forces Can Drive Investment in
Controllable DC “Bridges” Between Grids
WA
MT
ME
OR
ND
MN
NY
ID
WI
SD
WY
MI
IA
NE
RI
CT
PA
IL
NV
KS
UT
CA
WV
VA
KY
OK
NC
AZ
TN
AR
SC
MS
Note: Market Forces
Could Determine the
Number, Size and Location
of Regional
Interconnections
AL
NJ
DE
MD
OH
IN
MO
CO
NM
VT
NH
GA
TX
LA
FL
MA
“Islands and Bridges” – a “Unified Field Theory” of
Electric Restructuring?
• Improved Reliability – Contains Disturbances
Within a Single Synchronous Grid
• Enhanced Competition – Market Forces Determine
the Number & Size of DC Connections at the
Cross-Border “Seams”
• Enhanced Regulatory Oversight – Supports
Formation of Regional Planning Boards
• Reduced Environmental Impacts – Compact
Corridors, No EMF, Possibility of Underground
Placement of Cables
What’s Needed: Public Policies to Support
Development of a 21st Century Grid That Is...
Smart…
Strong…
and Flexible
American Superconductor Corporation
Thank You!
Questions?
[email protected]
www.amsuper.com