Deck 1 Flashcards
The loss of the magnetic bonds that bind together the elements of a power system is known as
All of the above
If a 2 pole generators rotor is spinning at 3601 rpm while the generator is connected to a 60hz system,how fast is the generators torque angle changing?
6 degrees per second
Neglecting losses, the difference between a generators mechanical power input and electrical power output is called
Accelerating power
Steady state instability
Slowly developing event
Transient instability
Rapidly developing event
Oscillatory instability
Excitation systems are common cause
According to the equal area criterion for transient stability
The decelerating area must at least match the accelerating area
A generator is angle unstable whenever its torque angle exceeds 90
False
High speed transmission protection is a benefit to angle stability because
All of the above
The primary difference between an out of step event and a fault is
The speed at which the impedance changes
When a power system is angle stable it has what 3 characteristics
Sustained generator torque angles of less that 90 degrees
Sustained power angles of less that 90 degrees
And a torque angle of 25 degrees
What are 3 classifications of angle stability
Steady state, oscillitory, transient
Angle stability is not like voltage control in which a system operator has the time to correct voltage deviation
True
For a generators torque angle to change there must be what
Accelerating power
What are two actions available to a system operator to assist with maintaining angle stability?
Maintaining system voltage levels as high as possible, maintaining system impedances as low as possible, ensure that generator voltage regulators are operated in automatic, ensure that high speed protective relay stems are in service as intended
