Power Factor Calculator
Estimate the capacitor bank compensation needed to improve power factor in an AC electrical system.
System Parameters
Input Parameters
Results update automatically when inputs change.
Results
Estimated compensation: 5.53 kVAR
Estimated reactive power compensation required to reach the target power factor.
Old reactive power8.82 kVAR
Target reactive power3.29 kVAR
Required compensation5.53 kVAR
Estimated capacitance per phase—
Planning estimate only. Confirm system configuration, capacitor ratings, harmonics, and equipment requirements with a qualified electrician.
How to use the calculator
- Select single-phase or three-phase AC and enter the system voltage.
- Enter the supply frequency and active power.
- Enter the existing power factor and your target power factor.
- Review the estimated reactive power compensation and capacitance per phase.
Assumptions and limitations
This calculator uses the ideal relationship Qc = P × (tan(arccos(PF₁)) − tan(arccos(PF₂))). Capacitance is estimated using the selected frequency and voltage. For three-phase systems, voltage is line-to-line and the selected delta or wye connection determines the per-phase capacitance estimate. Actual capacitor-bank selection must account for harmonics, switching, tolerances, voltage rating, protection, load variation, and local electrical codes. This tool is for planning only and does not replace professional electrical design.
