Busbar Insulation Inside Medium Voltage VFD Converter Panel

You should state your location. Codes or standards from elsewhere may not apply.

I would guess that uninsulated bus bars are acceptable with the described arrangements. Even if the bus bars were insulated, various connections would probably still remain exposed. If so, insulated bus bars could give a false sense of security.

Yes.

The only value in using bus insulation inside of any MV equipment is in when physical clearances between live parts is restricted beyond what is necessary. There is ZERO personnel protection value to insulating the bus, because on MV equipment one should NEVER be working on it live unless extreme precautions and personal protective equipment is used. insulating the bus changes nothing in that regard.

At this voltage, busbar insulation is NOT for people's protection . This is why there must be anyway other devices as interlocks to prevent access to live parts.

If there is some insulation, it is to ensure proper insulation, and decrease overall size of the equipment . Personnally, I prefer non insulated bars, as sleeving can gather dust, age, in other words change of dielectric properties. And at this rather low voltage, thermal considerations are probably more impacting the overall dimensions than insulating distances.