Paritian

Electricity

Power Factor Correction Calculator

Capacitor bank size in kvar needed to raise the power factor from one value to another.

Results

Reactive power 55.32 kvar
Apparent power 133.33 kVA
Apparent power 105.26 kVA
Capacitance 1100.62 µF
Current 192.45 A
Current 151.93 A
Percentage 21.05 %

What this tool does

A poor power factor means the supply carries current that does no useful work, and most industrial tariffs charge for it. This gives the reactive power a capacitor bank must supply to lift the power factor to your target, and shows how much the apparent power drops as a result.

Formula

Qc = P × (tan φ₁ − tan φ₂)

Variables

SymbolMeaningUnit
pActive powerkW
pf1Power factor
pf2Power factor
uuVoltageV
fqFrequencyHz
QcReactive powerkvar
S1Apparent powerkVA
S2Apparent powerkVA
CCCapacitanceµF
I1CurrentA
I2CurrentA
IRPercentage%

Worked example

  • Active power100 kW
  • Power factor0.75
  • Power factor0.95
  • Voltage400 V
  • Frequency50 Hz
  • Reactive power55.32 kvar
  • Apparent power133.33 kVA
  • Apparent power105.26 kVA
  • Capacitance1100.62 µF
  • Current192.45 A
  • Current151.93 A
  • Percentage21.05 %

Limitations

  • Electrical installations are governed by national wiring rules. Cable sizing also depends on installation method, grouping, ambient temperature and protection devices, which this calculator does not evaluate.
  • The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.