Download - EMS Users Group Meeting March 13, 2000
NERC Policy 10, draft 3 NERC Policy 10, draft 3
Proposed Standards and Measurements Proposed Standards and Measurements for the Building Blocks of Interconnection for the Building Blocks of Interconnection
ReliabilityReliability
EMS Users Group Meeting
March 13, 2000
Stephen P. Hoffman, ComEd
What is an IOS?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 ServicesInterconnected Operations Services
• Balance Supply and DemandBalance Supply and Demand
• Continuous
• Regulation• Load Following
• Post Contingency
• Frequency Response• Spinning Reserve• Non-Spinning Reserve
• Transmission SecurityTransmission Security• Reactive Power Supply from Generators
• Emergency PreparednessEmergency Preparedness• System Black Start Capability
Seconds Hour
Deployment Period
Minutes
Where We’ve BeenWhere 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
Where We’re Going***Where We’re Going*** 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 non-
technical 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 issuesSeven non-technical issues1. 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”IOS “White Paper” 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 10Need for Policy 10 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 IOSAncillary Services Relative to IOS Ancillary services:
– are driven by regulatory objectives (open, non- discriminatory 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’ ObligationsOperating 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’ ObligationsOperating 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’ ObligationsSuppliers’ 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 ComparisonIOS and Ancillary Service Comparison
IOS Suppliers:Generators and
ControllableLoads
Policy 10ReliabilityControl Functions
•Regulation•Load Following•Contingency Reserves
•Frequency Response•Spinning•Non-Spinning
•Reactive Power Supply from Generation Sources•Unit Black Start
Raw Materials AssemblyProcess
Operating Authority:
System Controland Integration
Functions
Transmission Customers:•Loads•Generators•IOS Suppliers
ReliableTransmission
Service
•Scheduling Sys. Control & Dispatch•Reactive Supply & VC from GS•Regulation and Frequency Response•Operating Reserve- Spin•Operating Reserve- Supplemental•Energy Imbalance
Finished Product
Power variationsPower variations
Consists of changes in:– Load
– Generation
– Interchange
8000
9000
10000
11000
12000
13000
14000
15000
16000
17000
0
500
1000
1500
2000
2500
3000
3500
4000
Load, Generation, and Interchange over two days
Transition to definitionsTransition to definitions
RegulationLoad
FollowingContingencyReserves - Spinning &
Supplemental
DispatchableUnits
Energymarket
12800
12850
12900
12950
13000
13050
13100
13150
13200
13250
13300
1650
1700
1750
1800
1850
1900
1950
2000
2050
2100
2150 Any of the
IOS/Ancillary terms just divide this real variability into different categories.
FrequencyResponse
IOS Quantity relationshipsIOS 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 ProcessReal Energy Demand - Supply Balance Process
Real energy Demand-Generation BalanceVariability locatedwithin theOPERATINGAUTHORITY1
+ Area ControlError (ACE)2
OPERATING AUTHORITYresponds to ACE byissuing schedules to IOSSUPPLIERS. Thedynamic schedules aregenerated automaticallyby AGC, or manually bydispatcher action.3
IOSSUPPLIERSrespond todynamicschedules4
Total variability corrected by the OPERATING AUTHORITY5
Supplier Control ErrorSupplier Control Error 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 MeasurementsIOS Resource MeasurementsStatedCapabilities
Regulation -Range,Ramp rate,acceleration
Definedonce percontractperiod
Definedmany times percontractperiod
ObservedCapabilities
Power output,Range, and Ramp rate shortfalls fromstated
re-set events
SCEVariableSchedule
Scheduleparametersindicate “howmuch” of thestated capabilitieswere dispatched.
Useful forfinancialpurposes
Could alsoindicatedeliveryerror
IOS actualoutput
Indicatesdeliveryerror
Useful forreliabilityandfinancialpurposes
Regulation and Load FollowingRegulation and Load Following
Stated capabilities– Capacity
– Maneuverability Ramp Rate Acceleration Signal Update (Regulation = automatic;Load Following =
automatic or manual)
Reg & LF ScheduleReg & LF Schedule
310
315
320
325
330
335
340
345
350
0:02:00 0:04:00 0:06:00 0:08:00 0:10:00Time
Sch
edu
led
Ou
tpu
t
Schedule with AccelerationSchedule with Ramp RateControl Signal
HoldRaise Raise
Lower Lower
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
Regulation and Load Following Regulation and Load Following as seen by the Supplieras seen by the Supplier
CapacityManeuverabilityEnergy
Unit Providing Regulationor Load Following
MW
ControlSetpoint
Time
Min. LoadOn Control
Max. LoadOn Control
Two Units Following Control InstructionsFrom the Operating Authority
Manual Control
AutomaticControl
Reg & LF Criteria- several optionsReg & LF Criteria- several options
[StDev{|SCEsampled|}hour] < limit
– 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 limit.
Avg[ACE1 * SCE1]hour < SCEACElimit , and
Avg{|SCE1|}hour < SCElimit
– Where: SCE1 = one-clock minute average of the SCE.
CContingency Reserves - ontingency Reserves - Spinning and SupplementalSpinning and Supplemental
Stated Capabilities– Capacity
Maintain reserved capability at all times Load reserved capacity within (10-X) minutes
– Maneuverability Responsive to Operating Authority Control Signals
– Synchronized (spinning and frequency responsive)– Maintain an Operable Governor (frequency responsive)
Agree on the dispatch time “X”
98041
-10 0 10 20 30 40 50 60TIME (minutes)
MW
OU
TP
UT
No DCSrequirement
Time toredeployreserves
+Y% 0%
Contingency
±10% of reserves
Requestedreserves
TDCS
Contingency Reserve Schedule & Criteria
Frequency ResponseFrequency Response
Frequency Response Capabilities– Capacity– Maneuverability
Frequency Response Characteristic
F, Hz
FRi, MW
F, Hz
FRi, MW
+DB
-DB F, Hz
FRi, MW
+DB
-DB
FSi
Frequency ResponseFrequency ResponseSchedule and CriteriaSchedule and Criteria
Frequency Response Characteristic
SCE > 0% of the requested MW amount during disturbance recovery.
Bulk Transmission SecurityBulk Transmission Security(Reactive Power Supply from Generation (Reactive Power Supply from Generation
Sources)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.
MVar
MW
Rated Power Factor
ReactiveSupply for
VoltageSchedule Support
Potential Reactive Reserves
Reactive Power SupplyReactive 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 StartBlack 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 ImpactsIOS 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
CertificationCertification Demonstrates ability to perform a service Inverse relationship between ability to measure
and certification difficulty Important for Reliability & market design
Deployment FrequencyRare Continuous
Difficulty
Simple
Rigorous
Black Start Regulation & Load Following
Certification TestPerformance Metric
Contingency Reserves &Reactive Power Supply
Provides customers assurance they are paying for a real product
De-certification???
Certification - RegulationCertification - Regulation Mutually agree on 60 minute test period Confirm time via phone circuits Operating Authority
– 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 FollowingCertification - 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
Certifying entity– performs correlation coefficient test– issues certification
Certification - Contingency ReservesCertification - 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
Certifying entity– ensures that actual is between 100% and Y% of CR amount
– issues certification
Certification - Reactive SupplyCertification - 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 ResponseCertification - 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 CapabilityCertification - System Black Start Capability
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 TestBasic 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 TestLine 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 TestLoad 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 CertificationBlack Start Certification
Certification is issued upon:– 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 examplePractical exampleContingency ReservesContingency Reserves
Three Ancillary Service supply options:– purchase from CA,
– purchase from third party, or
– self provision
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.
ConclusionConclusion
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