What is power factor?
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The power factor of an AC electric power system is defined as the ratio of the real power flowing to the load to the apparent power, and is a number between 0 and 1 (sometimes expressed as a percentage; 0.5pf is 50% pf). Real power is the capacity of the circuit for performing work in a particular time. Apparent power is the product of the current and voltage of the circuit. Due to energy stored in the load and returned to the source, or due to a non-linear load that distorts the wave shape of the current drawn from the source, the apparent power can be greater than the real power. A device that draws an apparent power of 1kVA and has a 0.5pf consumes 500W, not 1kW. Because of the costs of larger equipment and wasted energy, electrical utilities usually charge a higher cost to industrial or commercial customers where there is a low power factor. Power factor correction (PFC) is therefore often used to make reactive loads look more like resistive loads. |
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| 2012-05-02 | Address flicker, dimming challenges in LED lamp design A two-stage power factor correction scheme can be used to eliminate line-frequency ripple and the resulting flicker at the output of LED solid-state lights. |
| 2012-04-03 | TI's LED driver features flicker-free dimming TI's TPS92310 TRIAC dimmable LED driver with PFC correction, features both full-range and flicker-free dimming. |
| 2012-02-27 | MEMS accelerometer boasts high stability Kionix's KXTJ2 tri-axis MEMS accelerometer boasts low power, high performance and a small form factor of 2 x 2 x 0.9mm. |
| 2011-12-29 | R2A20113A power factor correction controller R2A20113A power factor correction controller |
| 2011-12-13 | Offline regulator eliminates opto-isolator Linear's LT3798 is an isolated flyback controller that eliminates the opto-isolator or signal transformer for feedback since the output voltage is sensed from the primary-side flyback signal. |
| 2011-12-14 | Use active PFC offline LED controller for primary-side control Read about a power solution touted to reduce component costs and improve overall energy efficiency. |
| 2011-11-22 | PFC controller reduces harmonic distortion ADI unveils dual-phase ADP1048, claimed as first digital PFC controller that offers highly accurate AC power metering capability. |
| 2011-08-23 | ATR system targets rugged apps X-ES launches the XPand6000, claimed as ultra-small form-factor ATR system for rugged applications with severe size, weight, and power constraints. |
| 2011-07-22 | Power supply IC targets 85W–1kW PFC apps Power supply IC targets 85W–1kW PFC apps |
| 2011-06-16 | High-voltage LED power supply minimises parts count High-voltage LED power supply minimises parts count |
| 2011-06-16 | Avoid audible noise at light loads when using triggered PFC converters Know how to address the issue of audible low noise when using a triggered power factor controller. |
| 2011-05-17 | IC packs PFC, ballast control IR's IRS2580DS Combo8 IC comes in a compact 8-pin SO-8 package that integrates power factor correction (PFC) and ballast control in a single IC. |
| 2011-04-26 | LED control IC combines PFC, half-bridge driver IR's IRS2548D Switched Mode Power Supply (SMPS) LED control IC combines Power Factor Correction (PFC) and half-bridge driver in a single IC offering greater than 88 per cent efficiency. |
| 2011-03-24 | PFC ICs operate over 85-264VAC input line range IR's IR115x family of µPFC ICs offer high PF, low total harmonic distortion and DC Bus regulation while decreasing component count, PCB area and design time compared to traditional solutions. |
| 2011-03-17 | PFC ICs enhance system protection in AC-DC apps IR's IR115x family of µPFC power factor correction ICs promise high PF, low total harmonic distortion and excellent DC Bus regulation for AC-DC applications. |
| 2011-03-14 | Full-bridge PWM controllers pack MOSFET gate drivers National's LM5045 and LM5046 PWM controllers ease the design of full-bridge topology-based power converters into small form factor power supplies by reducing the number of external power components. |
| 2011-03-08 | LED ref design aimed at candelabra bulb substitute Power Integrations reveals the RD-268 design, a reference design for candelabra-style replacement bulbs that features TRIAC dimming support, low total harmonic distortion (THD), and high power factor. |
| 2011-02-14 | PFC LED driver IC designed for space-constrained apps iWatt debuts its first power-factor-corrected (PFC) LED driver IC with primary-side-regulated, leading- and trailing-edge-dimmable, AC/DC Digital PWM Controller. |
| 2010-12-27 | 120 V high power factor dimmable CFL with UBA2014 120 V high power factor dimmable CFL with UBA2014 |
| 2010-12-14 | LED driver IC promises high power factor at low cost LED driver IC promises high power factor at low cost |
| 2010-11-30 | LED controller improves efficiency with PF correction TI rolls out the TPS92210, a single-stage, TRIAC-dimmable LED lighting pulse width modulation (PWM) controller solution that offers single-stage power factor correction for improved efficiency. |
| 2010-11-19 | Constant current LED drivers extends over 12W to 20W Element14 has just announced the latest RECOM AC/DC LED solutions which packs universal AC inputs, power factor correction. |
| 2010-11-16 | AC-DC converter packs PFC correction Vicor Corp. delivers PFM VI BRICK module, an isolated AC-DC converter that offers isolation, voltage transformation and PFC regulation in a single stage. |
| 2010-10-08 | LED drivers offer built-in power factor correction LED drivers offer built-in power factor correction |
| 2010-09-29 | PFC controller IC features zero current switching Allegro MicroSystems Inc. reveals the SSC2101S, a dual-phase DCM interleaved PFC controller IC for use in the telecom, server, home appliance and industrial markets. |
| 2010-09-16 | EVL250W-ATX80PL: 80 PLUS Silver 250W ATX SMPS demonstration board This application note describes the characteristics and performance of a 250W wide range input and power factor corrected power supply designed to be used in an ATX app. |
| 2010-07-27 | Industrial apps reap benefits from PFC device This article explains the different power types that an electricity meter measures, power factor and power factors' implications on power measurement. |
| 2010-07-28 | 3kW fixed-off-time (FOT) power factor correction 3kW fixed-off-time (FOT) power factor correction |
| 2010-07-26 | UCC28070 300W interleaved PFC pre-regulator design review This application note reviews the design of a 300W two-phase interleaved power factor corrected (PFC) pre-regulator. |
| 2010-07-12 | LED driver integrates PFC, step-down AC/DC An offline LED driver from ON Semiconductor integrates power-factor correction (PFC) and isolated step-down AC-DC power conversion in a single stage. |
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