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Flashcards in SOS Study Deck (22):

What is a Interconnection Reliability Operating Limit (IROL)

A System Operating Limit that, if violated, could lead to instability, uncontrolled seperation, or Cascading outages that adversely impact the reliability of the Bulk Electric


What is a System Operating Limit (SOL)

The value (such as MW, MVar, Amperes, Frequency or Volts) that satisfies the most limiting of the prescribed operating


What is Impedance

A measure of the total opposition to current flow in an alternating current circuit. It has two components; resistance and reactance


What is Phase Angle

The angular separation between the current and voltage cycles


What is Power Angle

The voltage angular difference between two locations in the power system


The AVR regulates the amount of DC applied to the?



Real power or MW's flow in which direction?

from the higher power angle to the lower power angle (could also be said higher voltage angel to lower voltage angle)


Reactive power or MVAR flow in which direction

from the higher voltage magnitude to the lower voltage magnitude


Impedance is made up of?

Capacitance, Inductance and Resistance


What is steady state stability

when the system parameters such as voltage, frequency and power flows may be changing but the changes are small and occur gradually


What is Transient stability

the ability of the power system to overcome a situation where a sudden, large change takes place on the sytem without violating SOL's. Could be a loss of generator and sever system fault.


What is Transient Instability

when the power system operates at an angle of 90 degress or more can be caused when heavy power transfers occur in the system as with a loss of genreation


Generator ratings specify the __________ and ___________ at which they can operate safely

voltage and frequency


What part of the operating reserve is used to meet CPS

Regulating reserve


What part of operating reserve is used to meet DCS

Contingency reserve, spin and non spin


If two systems are severely out of synch (large frequency difference) what is likely to be reported on the synced scope

A vibrating indicating needle


Firm load shed for continuity of the BES of how much MW's needs to be reported to NERC

100 MW or more


Loss of firm load > or = to ___________ requires reporting to NERC

Entities with > or = to 3000 MW reports loss of > or = 300 MW.

All other entities report loss of > or = 200 MW or 50% of total demand

Loss reported within 24 hours


Firm load reporting is how much to NERC

> or = 100 MW report time is 24 hrs


Which entities may determine the deviation of a dynamic schedule constitutes reliability concern? Who do they notify?

RC or TO and notify the PSE


Emergency plans should be review and updated by the TO and BA how often?



Emergency plans must include interim provisions if it is expected to take more then ________ to implement the contingency plan for loss of the primary control center?

60 minutes