Power Grid Operations & Management Flashcards
7 cards from real SOPD practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Power Grid Operations & Management flashcards as text
What is the primary purpose of automatic generation control (AGC) in power grid operations?
Answer: Automatically adjust generator output to maintain system frequency and scheduled tie-line flows
AGC automatically adjusts generator MW output to correct Area Control Error (ACE), maintaining frequency at 60 Hz and keeping net interchange on schedule.
During a voltage collapse scenario, which corrective action should a system operator take FIRST?
Answer: Energize shunt capacitor banks and request reactive support from neighboring areas
Energizing capacitors and obtaining reactive support restores reactive power margin and arrests voltage decline before more drastic actions are required.
A transmission line's thermal limit is reached at 115°C conductor temperature. What does this limit protect against?
Answer: Excessive sag that could reduce ground clearance below safe minimums
High conductor temperatures cause thermal elongation and increased sag, reducing ground clearance and creating a safety hazard.
What does the term 'N-1 reliability criterion' require of a transmission system?
Answer: The system must remain stable and within thermal limits following the loss of any single element
The N-1 criterion requires that the bulk power system remain secure and within all limits after the sudden, unplanned loss of any single contingency element.
When a large generating unit trips offline unexpectedly, what is the immediate grid response?
Answer: System frequency declines as load exceeds available generation
Losing a large generator creates a power deficit; system frequency begins to drop until governor response and AGC restore the balance.
What is 'spinning reserve' in power system operations?
Answer: Generation capacity already synchronized to the grid and available to increase output within 10 minutes
Spinning reserve is synchronized, unloaded generating capacity that can be rapidly called upon to arrest frequency decline following a contingency.
A dispatcher observes that the Area Control Error (ACE) is persistently negative. What does this indicate?
Answer: The area is generating less than needed, causing underfrequency or excess imports
Negative ACE means the area is under-generating relative to its scheduled net interchange and frequency contribution, requiring an increase in generation.