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Short-Circuit & Per-Unit Studies

Per-Unit System: Base MVA, Base kV, Base Current and Base Impedance

A four-step walk through the per-unit system (base MVA, base kV, base current Ibase = Sbase ÷ (√3 Vbase), base impedance Zbase = Vbase² ÷ Sbase), with a worked example converting a 1.25 Ω transformer impedance to 0.1050 per unit on a 100 MVA, 34.5 kV base.

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