20th September 2020

Introduction to Power Factor Improvement

In this article, we will see in detail how about Power Factor Improvement. It is import to know new concepts before that for easy understanding.

Alternating Current(AC) power has three components Active power, Reactive power and Apparent Power.

Apparent power

Active Power(P): also called as real power or true power, it is the actual converted into output. unit of measurement of active power is Watt.

Reactive Power(Q): in simple terms, reactive power can best be described as the quantity of “unused” power that is developed by reactive components in an AC circuit or system. Unit of measurement of reactive power is Kilovar(kVAr).

Apparent Power(S): Vector sum of both active and the reactive components. unit of measurement of apparent power is Kilovolt Amperes (kVA).

In simple terms, Power factor is (Active power)/(Apparent power). In order to improve the power factor(Power Factor Improvement), reactive power should to as minimum as possible.

Presence of active power and reactive power always takes place in the electrical system, majorly due to inductive loads like motor etc.

Impact of reactive power

  • Higher KVA demand from the transformer.
  • Higher electricity cost
  • Higher voltage drop in the system
  • Increase losses of transformer, switchgear and cables.
  • Increase current flow for the load

It is thereby necessary to reduce and manage the reactive power to achieve higher efficiency of the electrical system and also reduce the cost of the electricity consumed.

Power factor improvement through power capacitor is the most cost-effective method to reduce and manage reactive power and improve the power factor.

Advantages of power factor improvement

  • Relief of penalty charges from the electricity board.
  • Better utilization of switchgear, cables and transformer.
  • Improvement in system voltage
  • Reduction in line current.
  • Reduction in kVA demand

Low power factor is a huge problem for the power systems, So power factor correction is required. Many methods are used for power factor correction. Power factor is improved by applying capacitors or synchronous motors are also used for power factor correction and these synchronous motors are known as synchronous condenser.

Relevant articles: Introduction to Power Factor, Power factor improvement using a power capacitor.