
Power Factor correction using a static capacitor
Calculation formulas as follows:
- Q1 = I losses + Cu losses
- Q2 = PkW · (Tanφ1 – Tanφ2)
- I losses = 2% · Str
- Cu losses = USC% · Str
- Q = Q1 + Q2
Where:
- Q1 = Reactive power to be compensated at the terminals of a transformer due to no load and load losses.
- Q2 = Reactive power to be compensated due to total reactive components of lighting, power and mechanical loads.
- Q = Overall reactive power to be compensated to achieve target power factor.
- I losses = Transformer no load losses = Iron core losses.
- Cu losses = Transformer load losses = Copper losses.
- Str = Transformer rating (KVA).
- P = Maximum demand load on the Main distribution board (kW).
- φ1 = Inverse cosine of power factor before compensation.
- φ2 = Inverse cosine of target power factor.
- Usc% = Short circuit percentage impedance voltage of the transformer.
Power Factor Values assumptions before compensation:
- For lighting outlets = 0.96
- For power outlets and receptacles = 0.8
- For motors = 0.8
Inputs = Transformer size + Transformer type + kVA Max. demand load for the whole system + PF before compensation + Target value of PF.
Outputs = Reactive power to be compensated at the terminals of a transformer due to no load and load losses.
- Reactive power to be compensated due to total reactive components of lighting, power and mechanical loads
- Overall reactive power to be compensated to achieve target power factor + circuit breaker size required to protect the capacitor bank.
Software: | Power factor correction calculations for power system – MS Excel Spreadsheet |
Version: | – |
Developer: | Mahmoud Salama |
Size: | 126 KB |
Price: | FREE |
Download: | Right here | Video Courses | Membership | Download Updates |

good very nice