hi !
i do need some REALLY SIMPLE literature about frequency controll of ac induction motor with squirell ' s cage , preferably with help of some microcontroller
my goal is to get a feel of how to create this at all , and to explain what is going on — without going deep into math or diffequations
can you advice me something please ?

 

Google VFD, variable frequency drive, lots of information available. Mostly used on 3phase motors, but up to a certain point they can be used to run a 3phase motor on single phase supply.

 

Do a search of Picmicro app notes. as per @shortbus, they do not work well with 1ph induction motors.
Max.