Question

A three phase star-connected load is drawing power at a voltage of 0.9 pu and 0.8 power factor lagging. The three phase base power and base current are 100 MVA and 437.38 A respectively. The line-to-line load voltage in kV is _______

Answer 1

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