Enter System Values
Formulas
MVA = √3 × kVLL × A ÷ 1000
A = MVA × 1000 ÷ (√3 × kVLL)
Voltage is RMS line-to-line kilovolts. Current is RMS line current. MVA is total three-phase apparent power.
Example
A balanced 100 MVA transfer at 230 kV corresponds to approximately 251.02 A of line current.
A = 100 × 1000 ÷ (1.732 × 230) = 251.02 A
Assumptions and Use
- The system is balanced and three-phase.
- The entered kV is line-to-line voltage, not line-to-neutral voltage.
- MVA is apparent power, so power factor is not needed.
- This is a steady-state magnitude calculation and does not model losses, voltage drop, charging current, harmonics, or phase imbalance.
Use system study data and applicable operating limits when evaluating actual transmission or distribution equipment.