As already stated, if the motor is existing, your insulation may have been damaged, so be observant. Remember, as the voltage and frequency change, so does the current, as well as harmonics. This can be calculated at any given frequency, maybe not so easy, but!!
One of our clients, a very large chemical company (worldwide), now always requires the use of oversized shielded cable on all VFD driven motors. They also require the VFD to be one size larger than required by the HP of the motor. Since I haven't worked on any of their projects in awhile, I think they always buy Allen Bradley drives. I know one of the largest brand snacks makers always specifies Allen Bradley. There are other good drive manufacturers out there, Reliance, Ge, to name a couple.
And there are several ways to control them. Get some literature from your local Allen Bradley rep or supplier.
