plz tell me what is the design procedure along with simulation circuit for converting 440v,50Hz 3 phase ac supply to 440v,(0-100)Hz 3phase ac supply using rectifier and inverter( for controlling motor speed) :?: :? ?

 

First thing is to sit down and decide what are the parameters you need,
then you estimate if it is feasable to build it or simply buy one.
Common VFDs use 3-phase rectifier bridge and caps to create
DC "bus-voltage". Then you have some transistors that form 3phase output which is controlled by microcontroller. This is the most basic system. Modern VFDs check for many thing before and during operation.
Options are nearly endless...