RC Prep Flashcards
ACE
ACE=(NIa-NIs)-10B(Fa-Fs)-Ime
How often is ACE calculated
Every 6 seconds
Time error correction
+/-0.02 Hz for time error correction, offsets ACE by .20 or 20% (NIAs)
CPS1- Control Performance Standard
Calculated and evaluated monthly, CPS1 >/=100%
Rolling 12 month average <100% is non compliant
BAAL- BA Ace Limit
Cannot exceed for 30 minutes
BAAL High >scheduled frequency
BAAL Low < scheduled frequency
MSSC
Most severe single contingency, reviewed annually
Reportable DCS
Disturbance control standard
Less than MSSC or > 80% of MSSC
Within one minute of sudden decline of ACE–>More than 1 event occurring within that one minute equates to 1 event
Contingency event recovery period
Time frame from resource output to decline within the first one minute interval of a reportable BA contingency event and extending for 15 minutes thereafter
Exemptions to reporting DCS
RC declared EEA
Multiple contingency events and magnitude exceeds MSSC
Multiple balancing contingency events within the sum of the time periods defined by the cont. event recovery period and the contingency event restoration period whose combined magnitude exceeds the MSSC
Contingency reserve restoration period
Restore contingency reserve within 90 minutes of the end of the contingency event recovery period
DCS Requirement
Must achieve 100% ACE Recovery- NERC CR Form 1
Frequency and load relationship (thumbrule)
1% decrease in frequency results in 2% decrease in load (3% for inductive motors)
Governor dead band
+/- 0.036 Hz–>Will not see change in NIa in ACE equation if no governor response occurs from a change in frequency
Frequency Response Measure (FRM)
Median of all frequency response observed for frequency deviation events identified by NERC for previous year
FRM must be = or more (-) than its FRO
Frequency Response Obligation (FRO)
FRM must be = or more (-) than its FRO
Calculated each year
BA’s percentage of the interchange and load
FRSG- Frequency Response Sharing Group
Jointly meet FROs- must modify frequency bias to represent frequency bias setting for the combined area–>Either sum area or single FB setting for the combined area
BAAL-005 action if ACE cannot be calculated
ACE Requirements
> 30 minutes, BA inform RC within 45 minutes starting at the initial time ACE was not able to be calculated
Manually calculate at this time
Must be available 99.5% of year (45 hours)
Frequency metering equipment requirements
Accurate to 0.001 Hz and available 99.95% of year (4.5 hours)
Dynamic transfers
Dynamic schedules- reflected in NIs
Pseudo tie- used as virtual AGC in ACE equation- reflected in NIa
Developed as way to account for the generation and load in the appropriate BA’s ACE equation
AGC (Automatic Generator Control)
Partially replaces lost generation–>Contingency reserves return ACE to 0
Hydro can respond quick (2-5 minutes on AGC)
AGC Modes
Tie line bias- uses entire ACE equation
Flat frequency- Considers only frequency control- islanded or isolated BA
Flat tie line- Only interchange component- if frequency signal is unavailable or unreliable
Assessment period for interchange request
Time from ramp:
1 hour or less- 10 minutes
1-4 hours- 20 minutes
>4 hours- 2 hours
Assessment evaluation for interchange
Energy profile
Ramp
Scheduling path
ATC- Available Transfer Capability
ATC=TTC-CBM-TRM
CBM- Capacity benefit margin
TRM- Transmission reliability margin
ATC**- accounts for unscheduled flow
Reliability Adjustment Arranged Interchange
Modify schedule for reliability between only the source and sink BA
Must communicate to RC within 10 minutes if denied and reason for denial
Who confirms and and who is informed once interchange is confirmed?
Sink BA
- Source BA
- Intermediate BA
- Each RC
- TSP
- Purchasing and selling entity
TLR- Transmission Loading Relief (TLR)
Interchange transactions >5% may be curtailed to provide relief
How often are real time assessments performed by the RC and purpose?
Every 30 minutes- identify IROL exceedances
How long can a IROL exceed its limit?
30 minutes or Tv (Tv must be 30 minutes or less)
Who implements plan to prevent exceeding IROL/SOL?
RC
How often are plans, processes and procedures reviewed?
Every 15 months
GMD are more likely to occur in what terrain?
Igneous rock
Impacted equipment by GMD event?
Transformer with high side wye grounded windings >200kv
Who disseminates GMD info?
Designated RC
EEA Levels
EEA 1- All available generation resources in use, concerned about sustaining contingency reserves, non firm energy sails are curtailed
EEA 2- Load management procedures in effect, no longer able to provide energy requirements- BA has implemented Operating Plan to mitigate emergencies and still able to maintain minimum contingency
EEA 3- Firm load interruption imminent or in progress- unable to meet minimum contingency reserves
Who issues EEA?
RC
Time requirement for reviewing Operating Plans
30 days
Submitted by BA and TO to RC
Operating plan should include what?
Communication Pro
Controlling Actions
Coordination
Staffing levels
Requirement for review of changes to restoration plan with blackstart resources
Planned- prior to change
Unplanned- within 90 days of change
Requirement to verify blackstart plans?
Every 5 years through:
- Actual events
- Blackstart resource testing every 3 years
Training requirements for blackstart resources
TO- Annually
Switching Personnel- 2 hours every 2 years
GO- 2 hours every 2 years- starting unit and energizing bus
Blackstart resource testing requirements
Every 3 years
- No assistance from BES
- Energize a bus
TO and GO agreement for changes in blackstart resource ability
Within 24 hours if offline
Within 30 minutes if online
RC review of restoration plan frequency
Every 13 months
- Neighboring plan within 30 days and notification within 60 days if there is a conflict, resolved within 30 days
Island load shed thumbrule
6-10% will increase frequency 1 Hz
Load restoration thrumbrule
5% of online generation
Restoration drill training
2 drills/year
Annual training for RC
Each TO/GO every 2 years participate in drill
BCC (Back up control center) requirements
Implemented in 2 hours or less and maintained 2 hours or more
Performed annually
Differential relay (87)
Power in=Power out, closed zone of protection
Distance relay (21)
Open zone, uses PT and CT–>Z=V/I
Relay zones of protection
1- 90%
2- 120-150%
3- 150-300%
Overcurrent Relay
Back up to distance and differential
50- instantaneous
51- timed
Directional- 67
SIL- Surge impedance loading
@ SIL- Produced reactive power=consumed reactive power
>SIL- Inductive, voltage lowers
Capacitor equation
Rated*[(Bus voltage/Rated voltage)^2]
AVR Requirements
Must run in AVR unless:
S/u, S/d, testing
Notify SO within 30 minutes for a change in VR status, not required if within 30 minutes
Generator Transformer requirements
W/ in 30 days of request if the primary transformer windings are > generator terminal voltage, Gen. owner shall provide TO and TP w/:
- Tap settings
- Available fixed tap ranges
- Impedance data
DCS Compliance
100% to 15 minute recovery
CPS Compliance
> 100% (monthly)
Reportable manual load shed
> /= 100 MW
Reportable loss of firm load
> /=300 MW
BAAL
<30 minutes to get within bound
COM requirements for RC (primary/backup)
TO, BA, adjacent RC
COM requirement for BA (primary/backup)
RC, adjacent BA, TO, GO, DSP
Back up: RC, TO, adjacent BA
COM requirement for TO (primary/back up)
RC, adjacent TO, BA, GO, DSP
Back up: RC, BA, adjacent TO
Failure of comms
Notify affected entities within 60 minutes if >30 minutes
Testing of alt. comms
Once very month (TO, BA, RC)- must initiate corrective action within 2 hours to repair or replace
Requirement to report EOP-004 event
IAW Operating plan within 24 hours or 4PM the following business day
TOP-001 data validation
BA must validate data once every 90 days–>must be restored within 2 hours if lost
EOP-005, System restoration plan requirements
Reviewed annually and submitted to RC- within 90 days of unplanned changes, prior to any planned changes, verified every 5 years
Restoration drill plan review requirement
Every 13 months
RC review neighboring RC and TO plan within 30 days
If an issue arises, not. of conflict within 60 days and resolved in 30 days