Limited information means you need to make a few assumptions on power factor and efficiency.
Assume PF of 0.75 and efficiency of 90%
kVA = (kW / Power factor) / efficiency so kVA = (90 / 0.75) / 0.9 = 133.33 kVA
So 133.33 kVA minimum but better to add a little extra to be on the safe side
so 140 kVA or closest available unless you can provide more detailed information.
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