When to use this calculator
Estimate reactive compensation needed to raise an entered displacement power factor. Ideal steady sinusoidal correction requirement; harmonic resonance and switching design are not included.
Explore the ac power & reactance calculators for other questions in this topic. For a related calculation, use the RC Low Pass Cutoff Calculator: Find the minus-three-decibel cutoff of an ideal RC low-pass filter.
PUTTING IT INTO PRACTICE
Power Factor Correction: a worked example
The values below are an illustrative example, not a recommendation. Replace them with measurements or assumptions that match your question.
| Input | Example value |
|---|---|
| Real power (kW) | 100 |
| Initial displacement PF | 0.8 |
| Target displacement PF | 1 |
| Result | 75 kvar |
- Check the input labels and enter the example values above.
- Apply the relationship: Capacitive correction = kW × (tan(acos initial PF)−tan(acos target PF)).
- The result is 75 kvar, rounded for display.
How to interpret your result
Ideal steady sinusoidal correction requirement; harmonic resonance and switching design are not included.
Use RMS values in the AC power relationships. Apparent power is measured in VA and real power in watts. Pure-sine conversions and balanced three-phase equations only apply under their stated assumptions.
Frequently asked questions
Why can volt-amps differ from watts?
Apparent power is the RMS voltage-current product, while real power also reflects power factor. They are numerically equal only at a power factor of one.
When is the power factor correction calculator useful?
Estimate reactive compensation needed to raise an entered displacement power factor. Ideal steady sinusoidal correction requirement; harmonic resonance and switching design are not included.
How do I use the power factor correction calculator?
Enter real power (kw), initial displacement pf, target displacement pf. The result updates automatically. Use the units shown beside each input; the example values illustrate the method.
Which formula does this calculator use?
Capacitive correction = kW × (tan(acos initial PF)−tan(acos target PF)).
What should I check before using the result?
Ideal steady sinusoidal correction requirement; harmonic resonance and switching design are not included.
How are results rounded?
Scalar numbers display up to six decimal places, with scientific notation for very large or small values. Text, fraction, date and schedule outputs use the format described on the tool. Intermediate calculations use JavaScript floating-point arithmetic. Keep sensible precision for your measurements.
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