V = 0.9 pu. and cos ϕ = 0.8 lag.

Base power = 100 MVA

Base current = 437.38 A

P.U. value = Actual value / base value

Now, the base voltage \(= \frac{{MVA\;Base}}{\sqrt3\times{Base\;current}}\)

\({V_{Base}} = \frac{{100 \times {{10}^6}}}{\sqrt3\times{437.38}} = 132\;kV\)

Now, V_{actual} = 0.9 pu × 132 kV

⇒ **V**_{actual }= 118.8 kV

\( ⇒ {V_{L - L}} = {{{V_{actual}}}}\)

**V**_{L-L} = 118.80 kV