SOPD Emergency Procedures 2 — Questions and Answers
Question 1: During a voltage collapse emergency, what is the FIRST priority action for a system operator?
- Shed load to restore voltage above minimum limits (Correct answer)
- Contact neighboring utilities for emergency assistance
- Increase generation output at all available plants
- Notify NERC and file an OE-417 report
Correct answer: Shed load to restore voltage above minimum limits
Load shedding to restore voltage above minimum acceptable limits is the immediate priority to halt voltage collapse progression.
Question 2: A major transmission line trips due to a fault and automatic reclosing fails. What is the operator's next step?
- Attempt a manual reclose after verifying the line is de-energized (Correct answer)
- Immediately dispatch a crew without further analysis
- Reduce system load to pre-fault levels before any action
- Declare a system emergency and begin load shedding
Correct answer: Attempt a manual reclose after verifying the line is de-energized
A manual reclose attempt, after confirming the line is safe, is the correct next step when automatic reclosing has failed.
Question 3: What does the term 'islanding' refer to in power system emergency operations?
- A portion of the grid operating isolated from the main interconnection (Correct answer)
- Deliberate load shedding of a single geographic island
- A generation unit disconnected from the grid for maintenance
- A protective relay scheme that isolates a single bus
Correct answer: A portion of the grid operating isolated from the main interconnection
Islanding occurs when a section of the power system becomes electrically isolated and continues to operate independently from the bulk grid.
Question 4: Under NERC EOP standards, when must a Transmission Operator notify its Reliability Coordinator of an emergency?
- As soon as the operator becomes aware of a condition that could impact reliability (Correct answer)
- Only after load has been shed and the emergency is confirmed
- Within 24 hours of the emergency beginning
- Only when neighboring utilities are also affected
Correct answer: As soon as the operator becomes aware of a condition that could impact reliability
NERC EOP standards require immediate notification to the Reliability Coordinator as soon as a reliability-threatening condition is identified.
Question 5: A generator trips unexpectedly, causing system frequency to drop rapidly. Which automatic response activates first?
- Governor response (primary frequency control) (Correct answer)
- Automatic Generation Control (AGC)
- Under-frequency load shedding relays
- Emergency energy purchase from neighboring balancing authorities
Correct answer: Governor response (primary frequency control)
Governor response is the fastest automatic primary frequency control, reacting within seconds to arrest frequency decline.
Question 6: During a 'hot restart' of a tripped generator, what is the key concern for the system operator?
- Synchronizing the unit to the grid at the correct voltage, phase angle, and frequency (Correct answer)
- Ensuring fuel supply is adequate before attempting restart
- Clearing all protective relay targets before synchronization
- Notifying customers before the unit is reconnected
Correct answer: Synchronizing the unit to the grid at the correct voltage, phase angle, and frequency
Proper synchronization—matching voltage magnitude, phase angle, and frequency—is critical to prevent damage when reconnecting a generator.
Question 7: What is the purpose of an 'emergency energy transaction' during a system emergency?
- To import or export power with neighboring balancing authorities to restore system balance (Correct answer)
- To curtail interruptible customers to reduce system load
- To activate demand response programs within the balancing area
- To transfer load between substations via switching operations
Correct answer: To import or export power with neighboring balancing authorities to restore system balance
Emergency energy transactions allow balancing authorities to exchange power across interconnections to quickly address generation or load imbalances.
SOPD Emergency Procedures 2
During a voltage collapse emergency, what is the FIRST priority action for a system operator?