I request the respected professionals to give an idea of software to control the power factor using a microcontroller.

Please have a look at datasheet of a modern power-factor controller chip, like TDA4862:

http://www.infineon.com/cmc_uploa...da4862.pdf

and you will see how complicate this task is. You would have to implement all these measures and features, which TD4862 fabricates in a tiny SO8 package!! So, why to reinvent the wheel?

Kai