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o4) Mark() for the correct statement and (X) for false statement of the following 1. The transient stability can be lost because of short circuits, whereas less severe faults, such as disconnection of generation or a transmission lines, do not lead to the loss of transient stability. 2. An early fault clearing means better chances of maintaining system stability determined, then if A2< Al the system is stable. 4. The longest duration of disturbance may result in instability of the system. qual 5. The use of automatic reclosing circuit breakers improves system stability 6. Equal area criterion method is used to solve the steady- state stability problems. 7.Connecting more transmission lines in parallel may improve the system stability. 8. Equations describing the steady-state stability can be linearized. For the figure shown below which shows the solution for rotor angle 8, the system is likely to be stable. do dt

Answer 1

(1)the transient stability can be lost because of the short circuits , where as less serve faults,such as disconnection of generation or a transmission lines , do not lead to the loss of transient stability . (it is not correct)

here cause of the transient disturbances are due to shorts circuits, sudden load changes and inadvertent tripping of lines and generators.

(2)an early fault clearing means better chances of maintaining system stability .(it is correct)

(3)in equal area criterion the accelerating area A1 and decelerating area A2 are determined ,then if A2<A1 the system stable ( it is correct)

(4) the longest duration of disturbance may result in instability of the system .( it is correct)

(5) the use of automatic reclosing circuit breakers improves system stability .(it is correct)

(6)equal area criterion method is used to solve the steady -state stability problem .(it is not correct)

(7)connecting more transmission lines in parallel may improve the system stability (it is correct)

(8)equations describing the steady state stability can be linearized .fotr the these figure shows the solution for rotor angle , the system is likely to be stable .(it is correct)