How will a buck-boost converter work with a brief explanation?

Buck Converter: Its convert higher voltage to lower voltage:

Boost Converter: Its convert lower voltage to higher voltage.

Buck-Boost: Its convert higher to lower and vice vesrsa.


Schematic of Buck-Boost:

Application Notes for BUCK BOOST:

http://www.ti.com/lit/an/slva535a/slva535a.pdf

Buck Boost design

https://pdfs.semanticscholar.org/563e/256c04c29c64907ce5c1c0e66bf4d04439a7.pdf

Using above link you can easily design a buck boost converter.