Motor Power Factor Calculator

Power factor is calculated as the ratio of real power to apparent power: PF = P(kW) / S(kVA). It can also be expressed as cos φ, where φ is the phase angle between voltage and current.

Power factor in AC circuits represents the efficiency of power usage, ranging from 0 to 1. It indicates how much of the supplied power is actually used for useful work versus reactive power that doesn't perform work.

The power triangle is a visual representation showing the relationship between real power (P), reactive power (Q), and apparent power (S). It forms a right triangle where S² = P² + Q².

A good power factor is typically above 0.9. Industrial facilities often target 0.95 or higher to minimize reactive power charges and improve system efficiency. Unity power factor (1.0) is ideal but rarely achieved in practice.

A power factor of 0.75 means that only 75% of the supplied power is used for useful work, while 25% is reactive power. This indicates poor efficiency and may result in higher electricity costs and system losses.

Power factor correction requires adding capacitors to reduce reactive power. Calculate the required capacitance using: C = Qc / (2πfV²), where Qc is the reactive power to be compensated, f is frequency, and V is voltage.

For single-phase: PF = P / (V × I). For three-phase: PF = P / (√3 × VL × IL), where VL is line voltage and IL is line current. Three-phase systems are more efficient and commonly used in industrial motor applications.

Motors typically have lagging power factor due to inductive loads. Poor power factor increases current draw, causes voltage drops, reduces system capacity, and may result in utility penalty charges. Correction improves efficiency and reduces operating costs.