Power factor

Understanding power factor

Power factor is a measure of how effectively electrical power is being converted into useful work output in an electrical circuit.

It is a dimensionless quantity ranging from 0 to 1 and is expressed as a cosine of the phase angle between voltage and current in an AC (alternating current) circuit.

• Leading Power Factor: If the current leads the voltage in phase (e.g., in capacitive loads), the power factor is considered leading and is typically expressed as a positive value.
• Lagging Power Factor: If the current lags behind the voltage in phase (e.g., in inductive loads), the power factor is considered lagging and is typically expressed as a negative value.

A higher power factor (closer to 1) indicates a more efficient use of electrical power, while a lower power factor (closer to 0) suggests inefficient power usage.

Low power factor can result in increased energy costs and decreased efficiency in electrical systems. Power factor correction, often achieved using capacitors or inductors, can be employed to improve power factor and reduce energy losses in certain applications.