Calculator · Electrical Engineering
Power Factor Correction Calculator
A shunt capacitor supplies the reactive power a lagging load draws, raising the power factor from PF₁ to PF₂ while the real power stays unchanged. Single-phase correction only.
Inputs
Results
Required Qc
1.38 kvar
Capacitance C
83.04 µF
Initial Q₁ · φ₁
1.38 kvar · 36.87°
Target Q₂ · φ₂
0 var · 0°
| Real power (unchanged) | 1.84 kW |
|---|---|
| Reactive reduction | 1.38 kvar → 0 var |
Assumptions
- · single-phase shunt-capacitor correction of a lagging load; ideal compensation leaves the real power unchanged
Explore in the Lab
Compare before/after in the Power & Three-Phase Lab
Carries P, PF₁, PF₂, V and f.
Technical reference
Qc = P · (tan φ₁ − tan φ₂)
C = Qc / (ω · V²)
tan φ = √(1 − PF²) / PF
- P
- real power (> 0)[W]
- PF₁, PF₂
- initial and target power factor, PF₂ ≥ PF₁
- V
- RMS voltage (> 0)[V]
- f
- frequency (> 0)[Hz]
Reference: P = 1840 W, 0.8 → 1.0, 230 V, 50 Hz → Qc ≈ 1380 var, C ≈ 83 µF.
The target PF must not be lower than the initial PF.
Single-phase formula only; it is never applied to a three-phase bank.