Transcript Proposed Standards for Interconnected Operations Services

NERC Policy 10, draft 3
Proposed Standards and Measurements
for the Building Blocks of Interconnection
Reliability
Stephen P. Hoffman, ComEd
EMS Users Group Meeting
March 13, 2000
What is an IOS?

required to achieve one (or more) reliability
objectives:
– generation/load balance (continuous and post
contingency)
– transmission security
– emergency preparedness
measurable
 higher cost or effort.
 separable & distinct
 usually provided by generators

Interconnected Operations Services
• Balance Supply and Demand
Deployment Period
• Continuous
• Regulation
• Load Following
Seconds Minutes
• Post Contingency
• Frequency Response
• Spinning Reserve
• Non-Spinning Reserve
• Transmission Security
• Reactive Power Supply from Generators
• Emergency Preparedness
• System Black Start Capability
Hour
Where We’ve Been

IOSWG Report Issued March, 1997

Decision to convert IOSWG report to Policy
10 by EC/OC April 1997
IOSITF formed September 1997
Policy 10 R1 posted April, 1998
Policy 10 R2 posted December, 1998
Policy 10 Adopted as White Paper, July 1999
Policy 10 R3 posted December, 1999
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Where We’re Going***
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IOSITF to issue responses to public comments
IOSITF submits draft 3.1 for NERC OC approval and MIC
concurrence in March 13-15, 2000
NERC Board Approval - May 2000
Assign subcommittee to resolve solutions to 7 nontechnical issues in implementation of Policy 10.
Compliance Templates (Metrics) for Policy 10 to be posted
summer 2000
Effective date of Operating Policy 10 and associated
compliance templates in their entirety January 2002
*** Future plans subject to change!
Seven non-technical issues
1. Distinction between NERC IOS and FERC Ancillary Services
2. Allow implementation of Policy 10 in a manner that adheres to
reliability principles yet accommodates differences in emerging market
structures.
3. Prepare to file Operating Policy 10 with FERC.
4. Determine the necessary requirements for independence of the
Operating Authority from commercial interests.
5. Determine the applicability of Operating Policy 10, in particular, how
the Policy applies to traditional, vertically integrated utilities.
6. Recognize the potential interactions of Policy 10 with Policies 1-9.
7. Coordinate remaining steps to enact Operating Policy 10.
IOS “White Paper”

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Approved by the NERC SC in July 1999
Contains IOS Standards
– Defines IOS
– Describes obligation of Suppliers and
Operating Authorities
– Defines IOS Resource certification
Contains IOS Metrics
– Describes measurement of delivery
– Proposes method for determining adequate
delivery
Need for Policy 10
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Lack of standards will result in inconsistent practices, which
may undermine reliability.
Assists industry restructuring initiatives:
– Corporate realignment or functional unbundling
– Divestiture
– Operational Unbundling
– Evolving markets
Operating Authorities (OA’s) may no longer own nor have
inherent “rights” to resources that supply IOS
Nothing is free. Formal agreements/protocols will replace
informal arrangements.
Ancillary Services Relative to IOS

Ancillary services:
– are driven by regulatory objectives (open, nondiscriminatory transmission access, equitable cost
recovery)
– provide a means to recover costs (i.e. collect revenues)

IOS:
– constitute “building blocks” (physical capabilities)
needed to support reliability
– have always existed, and will always exist under some
name
– are combined and deployed to provide ancillary services
– Accommodate local/regional needs
Operating Authorities’ Obligations

Determine and publish IOS requirements***
–
–
–
–
–
–

quantity
response times (if applicable)
location (if applicable)
metering & telecommunication requirements
Tx service requirements
process for arrangement, provision and deployment
*** Use inclusive, open process to establish
regional/local requirements
Operating Authorities’ Obligations
Arrange for and deploy IOS to meet
reliability obligations
 Adapt and modify requirements in response
to system conditions
 Monitor supplier’s performance

Suppliers’ Obligations
Deliver stated capabilities
 Certify resources as required
 Provide and maintain required metering &
telecommunication facilities
 Provide information needed to verify
performance
 Notify Operating Authority of changes in
capability

IOS and Ancillary Service Comparison
Raw Materials
IOS Suppliers:
Generators and
Controllable
Loads
Policy 10
Reliability
Control
Functions
•Regulation
•Load Following
•Contingency
Reserves
•Frequency
Response
•Spinning
•Non-Spinning
•Reactive Power
Supply from
Generation Sources
•Unit Black Start
Assembly
Process
Finished
Product
Reliable
Transmission
Transmission
Operating
Service
Customers:
Authority:
•Loads
System Control
•Generators
and Integration
•IOS Suppliers
Functions
•Scheduling Sys. Control & Dispatch
•Reactive Supply & VC from GS
•Regulation and Frequency Response
•Operating Reserve- Spin
•Operating Reserve- Supplemental
•Energy Imbalance
Power variations
 Consists
of changes in:
– Load
– Generation
– Interchange
17000
4000
16000
3500
15000
14000
3000
2500
13000
2000
12000
11000
10000
1500
1000
9000
500
8000
0
Load, Generation, and Interchange over two days
Transition to definitions

Any of the
IOS/Ancillary
terms just divide
this real
variability into
different
categories.
Frequency
Response
Regulation
13300
2150
13250
2100
13200
2050
13150
2000
13100
1950
13050
1900
13000
1850
12950
1800
12900
1750
12850
1700
12800
1650
Load
Following
Contingency
Reserves Spinning &
Supplemental
Dispatchable
Units
Energy
market
IOS Quantity relationships
Definitions and associated rules determine
how much is needed for each bucket.
 Total amount is the same, so rules just shift
amounts from one bucket to another.


Examples:
– generation scheduling method impacts the amount of
Regulation needed.
– Capacity bought with rights to dispatch serves any
Load Following need.
– 16 hour energy schedule increases variability that must
be corrected with another resource.
IOS Measurements
Lots of details & possibilities
 Is there a single number to “measure” one
service?
 Some measurement objectives are tied to
desired financial terms.

– frequency of CR deployment
– variability of Regulation schedule
– Measure capability shortfalls?

Some measurement objectives measure
whether reliability was maintained
– did the resource follow the request?
Real Energy Demand - Supply Balance Process
Real energy DemandGeneration Balance
Variability located
within the
OPERATING
AUTHORITY1
+
Area Control
Error (ACE)2
OPERATING AUTHORITY
responds to ACE by
issuing schedules to IOS
SUPPLIERS. The
dynamic schedules are
generated automatically
by AGC, or manually by
dispatcher action. 3
IOS
SUPPLIERS
respond to
dynamic
schedules4
Total variability corrected by the O PERATING AUTHORITY 5
Supplier Control Error
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Any dispatch request can be expressed as a
variable schedule.
SCE = actual - scheduled
Need to measure SCE average and “variability”
IOS are used to correct for SCE
a resource can both supply, and consume, IOS
schedule respects stated (agreed to) resource
capabilities
If a resource is providing several products, the
purchasing entities need to agree how to divide the
single delivery error.
IOS Resource Measurements
Stated
Observed
Variable
Capabilities Capabilities Schedule
Regulation Range,
Ramp rate,
acceleration
Power output,
Range, and
Ramp rate
shortfalls from
stated
re-set events
Defined
once per
contract
period
Defined
many
times per
contract
period
Schedule
parameters
indicate “how
much” of the
stated
capabilities
were
dispatched.
Useful for
financial
purposes
SCE
IOS actual
output
Indicates
delivery
error
Could also
indicate
delivery
error
Useful for
reliability
and
financial
purposes
Regulation and Load Following

Stated capabilities
– Capacity
– Maneuverability
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Ramp Rate
Acceleration
Signal Update (Regulation = automatic;Load Following =
automatic or manual)
Reg & LF Schedule
Sc he dule d O ut put
350
Sc h e dule wit h A c c e le r a t io n
Sc h e dule wit h R a m p R a t e
C o n t r o l Sign a l
345
340
335
330
325
320
315
H o ld
R aise
L o w er
R aise
L o w er
310
0 :0 2 :0 0
0 :0 4 :0 0
0 :0 6 :0 0
Tim e
Pt+1 = Pt + Rt * dt + 1/2 * Jt * dt2
Rt+1 = Rt + Jt * dt
Subject to:
Pmin < Pt < Pmax Rmin < Rt < Rmax Jmin < Jt < Jmax
0 :0 8 :0 0
0 :1 0 :0 0
Regulation and Load Following
as seen by the Supplier
Unit Providing Regulation
or Load Following
Two Units Following Control Instructions
From the Operating Authority
Max. Load
On Control
Control
Setpoint
Capacity
Maneuverability
Energy
MW
Manual
Control
Automatic
Control
Min. Load
On Control
Time
Reg & LF Criteria- several options

[StDev{|SCEsampled|}hour] < slimit
– Where: SCEsampled = Supplier Control Error at the sampled rate
(e.g., every minute).
– Meet this limit 90% of the periods in each month
– The Operating Authority would select the numerical value of slimit.
Avg[ACE1 * SCE1]hour < SCEACElimit , and
 Avg{|SCE1|}hour < SCElimit

– Where:
SCE1
= one-clock minute average of the SCE.
Contingency Reserves Spinning and Supplemental
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Stated Capabilities
– Capacity
Maintain reserved capability at all times
 Load reserved capacity within (10-X) minutes
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– Maneuverability

Responsive to Operating Authority Control Signals
– Synchronized (spinning and frequency responsive)
– Maintain an Operable Governor (frequency responsive)

Agree on the dispatch time “X”
Contingency Reserve Schedule & Criteria
TDCS
Frequency Response
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Frequency Response Capabilities
– Capacity
– Maneuverability
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Frequency Response Characteristic
FRi, MW
FRi, MW
FRi, MW
FSi
+DB
F, Hz
-DB
+DB
F, Hz
-DB
 F, Hz
Frequency Response
Schedule and Criteria
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Frequency Response Characteristic

SCE > 0% of the requested MW amount
during disturbance recovery.
Bulk Transmission Security
(Reactive Power Supply from Generation
Sources)

Continuous
– Reactive Power Supply to follow
voltage schedules

Event Response
– Reactive reserves activated by
an automatic voltage regulator
(AVR) in response to a sudden
voltage change.
Rated Power Factor
MVar
Reactive
Supply for
Voltage
Schedule
Support
Potential
Reactive
Reserves
MW
Reactive Power Supply

Reactive supply capabilities
– Reactive Capacity (both leading and lagging)
 Maintain reserved reactive capability at all times
– Maneuverability
 Responsive to Control Signals
– Respond to voltage schedule updates
– Maintain an operating Automatic Voltage Regulator
(AVR)
 Criteria
– Error is maintained less than an Operating Authority specified
band
– AVR status is maintained
Black Start

Black Start Capabilities
– Capability to start a self-starting unit within a time specified.
– Capability of picking up external load within a specified time.
– Stated MW capacity and energy capability of the System
Black Start Capability unit or units.
– Frequency response and voltage control capability.

Certification tests, and actual performance during an
event.
IOS Measurement Impacts

Additional control center (EMS?) capabilities will
be needed to:
– calculate IOS performance, and
– track variables tied to IOS financial settlement.
In general, will need to track requests in
future, whereas present practice largely
tracks actual output
 Will need to track intra-hour performance
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Certification
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Demonstrates ability to perform a service
Inverse relationship between ability to measure
and certification difficulty
Important for Reliability & market design
Contingency Reserves &
Reactive Power Supply
Rigorous
Difficulty
Black Start
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Regulation & Load Following
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Simple
Rare
Continuous
Deployment Frequency
Certification Test
Performance Metric
Provides customers
assurance they are
paying for a real
product
De-certification???
Certification - Regulation
Mutually agree on 60 minute test period
 Confirm time via phone circuits
 Operating Authority
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–
–
–
–
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sends raise & lower signals
signals remain unchanged for at least 1 minute
signals respect agreed-upon resource limits
record 1 minute average of schedule and actual output
Certifying entity
– performs correlation coefficient test
– issues certification
Certification - Load Following
Mutually agree on 60 minute test period
 Confirm time via phone circuits
 Operating Authority

– sends raise & lower signals
– signals remain unchanged for the pre-determined
minimum time between load changes
– sends at least 15 load change requests
– signals respect agreed-upon resource limits
– record 1 minute average of schedule and actual output
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Certifying entity
– performs correlation coefficient test
– issues certification
Certification - Contingency Reserves
Mutually agree on 8 hour test window
 Confirm time window via phone circuits
 Operating Authority

– selects actual time of test within the 8 hours (surprise test)
– request that resource provide its declared amount of Contingency
Reserves
– record 1 minute average of schedule and actual output
– record from 1 minute before notification until 19 minutes past TDCS
-X
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Certifying entity
– ensures that actual is between 100% and Y% of CR amount
– issues certification
Certification - Reactive Supply
Based on Planning Standards
 IOS Resource

– performs AVR tests as described in NERC Planning
Standards 2B M4 & 2B M6.
– Verifies and maintains its stated reactive capacity, as
described in NERC Planning Standards 2B M3.

Certifying entity
– verifies completion of all test criteria
– issues certification
Certification - Frequency Response
Mutually agree on test period
 IOS Resource

– record output changes in response to a test frequency
signal, or
– test that portion of the governor system that can be
tested if real power cannot be modified.

Certifying entity
– verifies completion of all test criteria
– issues certification
Certification - System Black Start Capability
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Composed of five parts:
–
–
–
–
–
control communication path
primary and alternate voice circuits
Basic Starting Test
Line Energizing Test
Load Carrying Test
– Many comments were received that some of the
last two tests were too difficult to perform.
Basic Starting Test
Mutually agree on a one week test window
 Operating Authority

–
–
–
–
selects actual time of test within the week (surprise test)
isolates IOS Resource from the power system
request that resource start within the agreed-upon time
ensure that the resource remains frequency and voltage stable for
30 minutes
Line Energizing Test
Isolate sufficient transmission as called for
in black start plan
 Conduct a Basic Starting Test
 monitor frequency & voltage at both ends of
line while energized by resource


ensure that the resource remains frequency and
voltage stable for 30 minutes
Load Carrying Test
Conduct a Basic Starting Test
 Conduct a Line Energizing Test
 Pick up sufficient load at the remote end of
the line


ensure that the resource and load remains
frequency and voltage stable for 30 minutes
Black Start Certification

Certification is issued upon:
–
–
–
–
–
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control communication performance
test primary and alternate voice circuits
One year Basic Starting Test
Three years Line Energizing Test
Six years Load Carrying Test
Provisions for revocation of certification
Practical example
Contingency Reserves

Three Ancillary Service supply options:
– purchase from CA,
– purchase from third party, or
– self provision
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OA(CA) just needs to dispatch resource
Which resources/suppliers form the pool of eligible
suppliers for Contingency Reserves?
Which resources/suppliers can actually be dispatched by
the reserve sharing system?
Certification helps to answer these questions.
Conclusion

Many of the concepts described in Policy 10
must be implemented, in some manner, as long
as the electric industry continues on the path to
deregulation