Grid Reliability 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 Grid Reliability flashcards as text
Which NERC reliability standard specifically addresses transmission planning to ensure the BES can withstand contingency events?
Answer: TPL-001-4
TPL-001-4 (Transmission System Planning Performance Requirements) establishes planning events and performance requirements for the Bulk Electric System.
In the context of grid reliability, what does 'N-1 contingency' mean?
Answer: The grid must survive the loss of any single element while serving load
N-1 contingency means the power system must continue operating reliably following the sudden loss of any single bulk power system element (generator, line, or transformer).
A power system operator observes frequency at 59.85 Hz. What is the most immediate concern?
Answer: Load is exceeding generation, risking further frequency decline
Frequency below 60 Hz indicates load exceeds generation; if not corrected, frequency will continue to drop, potentially triggering underfrequency load shedding relays.
What is the purpose of Operating Reserve — Spinning (also called Synchronized Reserve)?
Answer: To provide immediate active power response to frequency deviations using already-synchronized generation
Spinning reserve consists of generation capacity already synchronized to the grid that can rapidly increase output to arrest frequency decline following a loss of generation.
Which of the following best describes a 'Remedial Action Scheme' (RAS)?
Answer: An automated protection system designed to detect abnormal conditions and take pre-programmed corrective actions
A Remedial Action Scheme (also called Special Protection System) automatically detects system conditions and initiates pre-determined actions such as load shedding or generation tripping to preserve stability.
When evaluating thermal limits on a transmission line, what does the 'Emergency Rating' represent?
Answer: The maximum load the line can carry for a short duration (minutes to hours) beyond its normal rating
Emergency ratings allow a transmission element to carry load above its normal rating for a limited time period, providing operational flexibility following a contingency event.
A Transmission Operator (TOP) must notify neighboring TOPs and the Reliability Coordinator when which condition occurs?
Answer: A transmission element is operating outside its reliability limits
Operating outside reliability limits is an emergency condition requiring immediate communication with neighboring TOPs and the Reliability Coordinator per NERC standards.