ABSTRACT
One of the major applications for switching converters is power factor correction. Nonlinear loads in electronic systems degrade the quality of the power utility systems by reducing its power factor and injecting unwanted harmonics. As such, electric appliances or electronic systems drawing a sinusoidal current at a unity power factor, ideally behaving as a resistive load, are desired. Many electric appliances or electronic systems are designed to accept a universal-input AC voltage from the full range of European, Japanese, and North American mains, which span approximately from 85 to 264 Vrms. These systems must satisfy various regulations that limit the input current harmonic content, such as IEEE-519 or EN61000-3-2 (for equipment connected to the public low voltage distribution systems), and other standards for conducted and radiated emissions. There are also various national and industry standards as well as voluntary incentive programs, such as 80 PLUS® and Energy Star® programs, that require certain quality and energy efficiency from the power supply.
