Post on 13-Apr-2018
7/25/2019 Per-Unit and Base Impedance Calculation
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Change of Base Formula
Where:
ZBASE= Base Impedance
KVLL= Base Voltage (Kilo Volts Line-to-Line)
MVA3= Base Power
ABASE= Base Amps
ZPU= Per Unit Impedance
ZPU GIVEN= Given Per Unit Impedance
Z = Impedance of circuit element (i.e. Capacitor, Reactor,
Transformer, Cable, etc.)
XC= Capacitor Bank Impedance (ohms)
XC-PU= Capacitor Bank Per Unit Impedance
PER-UNIT AND BASE IMPEDANCE CALCULATOR
Calculator-1
Known variables:
Formulas and Variables
7/25/2019 Per-Unit and Base Impedance Calculation
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Capacitor Bank Per-Unit Calculations
Motor Per-Unit Calculations
MVAR3= Capacitor Bank 3-Phase Rating
X" = Motor Sub-Transient Reactance
LRM = Locked Rotor Multiplier
Background