Which method can improve a poor power factor?

Which method can improve a poor power factor?

• A. Installing inductors.
• B. Installing capacitors or other reactive-power sources.
• C. Reducing voltage.
• D. Increasing load.

Answer: (B)

Power factor describes how effectively the electrical power is being used, defined as the cosine of the phase angle between voltage and current. When loads are inductive, current lags voltage, increasing reactive power and lowering the power factor. The way to improve it is to add a source of reactive power that supplies leading reactive power to offset the lagging reactive power from the inductive loads. Installing capacitors or other reactive-power sources provides this leading reactive power, which cancels part of the lagging reactance and reduces the net reactive power. This raises the ratio of real power to apparent power, moving the power factor closer to 1. Conversely, adding inductors would worsen the lag, reducing the power factor; reducing voltage or increasing load doesn’t reliably correct the phase relationship and can even worsen efficiency.

Power factor describes how effectively the electrical power is being used, defined as the cosine of the phase angle between voltage and current. When loads are inductive, current lags voltage, increasing reactive power and lowering the power factor. The way to improve it is to add a source of reactive power that supplies leading reactive power to offset the lagging reactive power from the inductive loads.

Installing capacitors or other reactive-power sources provides this leading reactive power, which cancels part of the lagging reactance and reduces the net reactive power. This raises the ratio of real power to apparent power, moving the power factor closer to 1. Conversely, adding inductors would worsen the lag, reducing the power factor; reducing voltage or increasing load doesn’t reliably correct the phase relationship and can even worsen efficiency.