Power per unit problem

[electric]

Can someone help me with this partial per unit problem? The actual problem has couple of other generator but I got stuck with this very first step.

Problem:

Generator 1 rated as 100 MVA, 33 KV, reactance 10%. Determine the reactance of the generator corresponding to base values of 200 MVA, 35 KV.

Solution:

MVAB = 200 (given)

KVB = 35 (given)

X B = (KVB (L-L))2 /MVAB

= 352 /200 = 6.125

Xpu (new) = 0.1 (33/35)2 * (200/100) = 0.16 pu

Xactual = Xpu * XB = 0.16 * 6.125 = .98

The actual answer to this problem is Xg = 0.1777

 

[Flyer_PE]

Xpu (new) = 0.1 (33/35)2 * (200/100) = 0.16 pu

It appears you pretty much had the answer here. The per unit impedance on the new base is:

For new base MVA: ZpuNew=ZpuOld*(MVAnew/MVAOld)

For new base voltage: ZpuNew=ZpuOld*(kVOld/kVNew)^2

ZpuNew = 0.1*(200/100)*(33/35)^2 = 0.178 pu