Practice Test Geeks(SOPD) System Operator/Power Dispatching Practice Test
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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

  1. What is 'cascading failure' in the context of power grid reliability?

    Answer: A sequence of dependent failures where each outage increases stress on remaining elements, potentially leading to widespread blackout

    Cascading failure occurs when the loss of one element increases loading on others, causing additional trips in a self-reinforcing sequence that can collapse a large portion of the grid.

  2. Under NERC's FAC-001 and FAC-002 standards, what must a Transmission Owner do before connecting a new facility to the BES?

    Answer: Perform facilities connection requirements studies and obtain approval from the Transmission Planner/Operator

    FAC-001/002 require interconnection studies to ensure a new facility will not adversely affect bulk electric system reliability before it is connected.

  3. What is the role of the Wide-Area Measurement System (WAMS) and Phasor Measurement Units (PMUs) in grid reliability?

    Answer: They provide time-synchronized, high-resolution measurements of voltage angle and magnitude across the grid, improving situational awareness

    PMUs provide GPS time-stamped phasor data at high sampling rates (30+ per second), giving operators and reliability coordinators enhanced visibility into dynamic system conditions across wide areas.

  4. A system operator receives a Reliability Coordinator instruction to reduce inter-area flow on a specific path. What is the operator's obligation?

    Answer: Implement the RC's instruction immediately, as the RC has the highest reliability authority

    NERC standards require that Transmission Operators comply with Reliability Coordinator directives immediately; the RC has the highest authority and widest view of system conditions.

  5. What is 'reactive power compensation' and why is it critical to transmission system reliability?

    Answer: It involves supplying or absorbing reactive power (Mvars) to maintain acceptable voltage profiles across the transmission system

    Reactive power compensation — through capacitor banks, reactors, SVCs, or generators — is essential to maintain voltage within acceptable limits, since reactive power cannot be efficiently transported over long distances.

  6. In restoration operations, what is the correct sequence for reenergizing a transmission line after a fault?

    Answer: Verify relay targets are cleared, check for trapped charge, confirm protection is armed, then energize from the appropriate end per restoration plan

    Safe line restoration requires clearing relay targets, verifying protection readiness, and following the restoration plan sequence to prevent re-faulting or switching surges from damaging equipment.

  7. What is 'transfer capability' in transmission system operations, and how does it relate to reliability?

    Answer: The maximum amount of electric power that can be transferred reliably over a transmission path while satisfying all applicable reliability constraints

    Transfer capability defines the power flow limit on a transmission path that, if exceeded, could violate thermal, voltage, or stability constraints under normal or contingency conditions.