What is Power Factor?
Power factor is the ratio between real power (kW) and apparent power (kVA) in an electrical system. It indicates how effectively electrical energy is being converted into useful work. A low power factor means more reactive power is flowing, leading to higher losses and reduced system efficiency.
Why Correct the Power Factor?
Improving power factor offers several benefits:
- Reduced losses in cables and transformers.
- Lower electricity bills in systems where utilities charge penalties for low power factor.
- Improved voltage regulation, leading to better performance of equipment.
- Increased system capacity, as the same infrastructure can carry more useful load.
What is kVAR in Power Factor Correction?
Reactive power, measured in kilovolt-amperes reactive (kVAR), does not perform useful work but is essential for creating magnetic fields in motors, transformers, and inductive loads. By installing capacitor banks to supply the required kVAR locally, the reactive power demand from the grid is reduced.
The formula used by the calculator is: Qc=P×(tancos−1(PF1)−tancos−1(PF2))Q_c = P \times \left(\tan \cos^{-1}(\text{PF}_1) – \tan \cos^{-1}(\text{PF}_2)\right)Qc=P×(tancos−1(PF1)−tancos−1(PF2))
Where:
- QcQ_cQc = required kVAR for correction
- PPP = real power in kW
- PF1\text{PF}_1PF1 = initial power factor
- PF2\text{PF}_2PF2 = target power factor
How to Use the Calculator
- Enter the real power (in kW or HP).
- Enter the existing power factor (PF₁).
- Enter the target power factor (PF₂).
- Optionally, add a percentage for future expansion load.
- Provide system voltage for reference (used for capacitor bank selection).
- Click Calculate to see the kVAR required for correction.
Applications
- Industrial plants: For capacitor bank sizing and distribution panel upgrades.
- Commercial buildings: To maintain power quality and avoid penalties.
- Utilities and consultants: For feasibility studies and energy audits.
- Educational use: For teaching electrical engineering concepts.
Final Note
This calculator provides quick guidance based on standard power factor correction equations. For critical projects, always verify results with detailed engineering design, manufacturer datasheets, and applicable electrical codes (IEC, IEEE, IS, NEC, etc.).
