SOPD Emergency Procedures 5 — Questions and Answers
Question 1: During a major storm, multiple transmission lines trip in rapid succession. What concept describes this type of failure progression?
- Cascading outage (Correct answer)
- Sequential switching
- Overload tripping sequence
- Coordinated protection operation
Correct answer: Cascading outage
A cascading outage is a sequence where each successive failure increases stress on remaining elements, triggering further trips in a self-reinforcing chain.
Question 2: An operator is directed to implement an 'emergency operating procedure' (EOP). Which statement is TRUE about EOPs?
- EOPs are pre-approved plans that operators execute without needing additional management approval during the emergency (Correct answer)
- EOPs require written approval from the reliability coordinator before implementation
- EOPs only apply to declared emergencies lasting more than four hours
- EOPs are optional guidelines that operators may adapt as they see fit
Correct answer: EOPs are pre-approved plans that operators execute without needing additional management approval during the emergency
EOPs are pre-approved procedures that operators are trained and authorized to execute immediately during emergencies without waiting for additional approvals.
Question 3: What is the role of the 'Reliability Coordinator' (RC) during a regional emergency?
- To have the widest view of the interconnection and coordinate emergency actions across multiple transmission operators (Correct answer)
- To directly control all generation dispatch within the affected balancing authorities
- To serve as the single point of contact for media inquiries during the emergency
- To authorize all load shedding actions taken by transmission operators
Correct answer: To have the widest view of the interconnection and coordinate emergency actions across multiple transmission operators
The RC has a broad system view and coordinates across multiple entities to direct actions that preserve reliability across the interconnection.
Question 4: A system operator notices that voltage at a critical 500 kV bus has dropped to 480 kV during heavy loading. What is the BEST immediate corrective action?
- Place additional reactive power resources in service (capacitor banks, SVCs, or generators in AVR mode) (Correct answer)
- Increase real power output from nearby generators to compensate
- Open the 500 kV line to redistribute load to lower-voltage paths
- Notify neighboring utilities and wait for their VAr support
Correct answer: Place additional reactive power resources in service (capacitor banks, SVCs, or generators in AVR mode)
Low voltage is caused by insufficient reactive power; the correct remedy is to supply additional VArs from available reactive resources.
Question 5: When restoring a black start unit to energize a transmission path, which sequence is correct?
- Energize transmission line, pick up auxiliary load on cranking path, then synchronize to the larger system (Correct answer)
- Synchronize all generators first, then energize the transmission lines
- Shed all load on the path, then energize from the high-voltage side
- Contact the reliability coordinator and wait for written authorization before any switching
Correct answer: Energize transmission line, pick up auxiliary load on cranking path, then synchronize to the larger system
Black start restoration requires energizing the cranking path first, picking up enough load to stabilize the unit, then carefully synchronizing to expand the energized island.
Question 6: During a widespread emergency, an operator receives conflicting instructions from the Balancing Authority and the Reliability Coordinator. Whose directive takes precedence?
- The Reliability Coordinator, who has the highest level of authority under NERC standards (Correct answer)
- The Balancing Authority, as the operator's direct supervisory chain
- The operator's on-site supervisor, who is accountable for the decision
- Neither; the operator must call NERC directly to resolve the conflict
Correct answer: The Reliability Coordinator, who has the highest level of authority under NERC standards
NERC standards establish the Reliability Coordinator as having the highest authority over reliability-related actions during emergencies, superseding balancing authority instructions.
Question 7: What is the significance of the 'time zero' concept in post-event analysis of a major disturbance?
- It identifies the initiating event from which all subsequent failures are sequenced to determine root cause (Correct answer)
- It marks when load shedding was first authorized by the reliability coordinator
- It represents the moment system frequency reached its lowest point
- It is the time at which the disturbance was first reported to NERC
Correct answer: It identifies the initiating event from which all subsequent failures are sequenced to determine root cause
Time zero is the moment of the initiating event; establishing it precisely allows investigators to reconstruct the exact sequence of failures in a cascading outage.
SOPD Emergency Procedures 5
During a major storm, multiple transmission lines trip in rapid succession.
What concept describes this type of failure progression?