Power Integrations highlights importance of power factor correction at APEC 2017 | EDN


Power factor correction is the process of improving a low power factor in a facility by increasing the ratio of real (working) power to apparent (total) power.

Power-factor correction allows the input current to continuously flow, reduces the peak input current, and reduces the energy loss in the power supply, thus improving its operation efficiency. Power-factor-corrected (PFC) power supplies have a power factor near unity (~1), and thus are highly efficient. The use of energy-efficient PFC devices, including uninterruptible power supplies (UPSs), can lead to significant cost savings.


  1. Tomi Engdahl says:

    Is Power Factor Correction Justified in the Home?

    Though PFC equipment may be warranted in industrial applications, an analysis of the energy savings enabled by this equipment in residential applications suggests its added cost to the consumer may not be justified.

    Recently, you may have noticed advertisements for a device that claims to reduce your monthly home electricity bills. The advertising literature states that you are paying for the added electricity that must flow when power factor (PF) is less than “unity” within your house. But to what extent does PF influence energy consumption? And do the energy savings accrued through power factor correction (PFC) justify the purchase of standalone PFC devices?

    Numerous pieces of equipment in the home are candidates for PFC. Some of these equipment types have capacitive inputs (for example, switching power supplies). However, some of the larger loads are the motor-driven appliances such as refrigerators and washing machines, which have inductive inputs.

    In the instance where a circuit has a PF less than unity, more current must flow to produce the desired electrical work. This additional current flow causes more power losses in the conductors located in the walls of your house, for which you derive no advantage except for a small amount of additional heat generated

    So Why PFC?
    PFC devices are used in some commercial or industrial applications where a company may have a large number of electrical motors that would have a significant effect on the PF of utility transmission lines, which span much longer distances than the cables in the home. Utilities may assess commercial or industrial customers a penalty for PF significantly less than one.

    Some appliance manufacturers are incorporating PFC into their finished products. The European Union’s International Electro-Technical Commission adopted the IEC61000-3-2 standard that required, by Jan. 1, 2001, all equipment needing 75 W of power or greater and less than 16 A to meet standards for harmonic generation and, thus, meet PFC requirements. Thereafter, Britain, China and Japan adopted similar standards. North America does not presently have these requirements.

    Where the mechanical load is reasonably constant (e.g., an air conditioner compressor motor), a PFC capacitor can be specified to produce a desired effect. Appliance manufacturers are faced with an interesting dilemma when including PFC into their finished products. They must convince their potential customers that over the product life, energy cost savings would equal or surpass the additional initial selling price, vis-à-vis a non-PFC item.

    It may be that the energy savings enabled by PFC on a global scale will, through a combination of legislation and economics, cause PFC to be incorporated universally into all electrical equipment.

  2. Tomi Engdahl says:

    Power Saver Scam EXPOSED!

    Power Saver devices are sold everywhere. But do they actually save power?! DON’T BE SHEEP!


    2 päivää sitten
    With the new “smart” meters they can unfortunately start charging for apparent power instead of real power. And that can be done remotely. If they do that then suddenly things with capacitive droppers like time switches and will cost about 10 times as much to run and most LED lamps will cost between twice and ten times as much to run depending on their circuitry.
    Sadly, a simple capacitor won’t fix most electronic power factor issues. But it’s a nice case and can be used as a shocker. (but with a much bigger capacitor)


Leave a Comment

Your email address will not be published. Required fields are marked *