Q$.1$ Choose the BEST correct answer

Transient stability solution method is:

a$)$ Numerical integration

b$)$ equal area criteria

c$)$ Newton Raphson

d$)$ a & b

The relative speed $({}_0)$ of the machine, this speed must go to zero over time for the machine stability.

a$)$ TRUE

b$)$ FALSE

When using equal area criteria, if $A1>A2$ then the system is:

a$)$ transient stable

b$)$ transient unstable

c$)$ critical stable

d$)$ dynamic stable

Q$.2[$see example$1]$

A generator supplying an electrical power given by $P_e=2\mathrm{.}5sin$ p$.$u$.$ to infinite busbar. The input mechanical power drive the generator $P_m=1p.u.$ If the mechanical drive change from $1$ to $1\mathrm{.}5$ p$.$u$.$ and the load angle increases until reached maximum value of $60$ find:

i$)$ the equilibrium angle ${}_{}$

ii$)$ The energy areas $A_1$&$A_2$ after $P_m$ changes

iii$)$ Is the system stable or not