Two good articles on power factor correction (and another on selecting/designing the magnetics)

TI’s announcement today of its UCC28060 power factor correction (PFC) control chip for 75 – 800W consumer applications reminded me of some useful PFC links I’ve come across lately.

Power-factor correction: Rx for medical power supplies from 1998 is one of the first how-to articles written about PFC, and gives an excellent general explanation, as well as some details for medical applications. Unfortunately, some of the equations have been garbled in the move from print to HTML, but this just serves as an excellent excuse to jump over them and get to the examples.

Politically incorrect power by the estimable Joshua Israelsohn gives a good update of PFC chips, especially as they relate to motor control. Don’t miss the comment by one skeptical reader that a PFC controller could completely do away with the need for good ol’ capacitors and inductors. Keep in mind that this was written two years ago, and chips have only gotten more sophisticated. The 28060 is a good example: The chip turns on or off phases of the power supply as the load varies so that only the phases required to power the load are enabled. 

…and Living with losses: Tips on using magnetic components doesn’t have that much to do with power factor correction theory, but it’s got some good tips for selecting/designing transformers and inductors.