What is the difference in the design of 10KW VFDs vs say 200KW VFDs. Is it only cooling and high power IGBTs? Can a low power VFD be simply scaled to any high power with only changing IGBTs alone ?
not likely
in addition to the IGBTs, you'll need to change the IGBT drivers, the snubbers,
the capacitors, the magnetics, and the sense and feedback circuits will need
at least some resistor changes.
Everything is bigger and more serious and parts are chosen not to fail, 290 A / phase on a 400V L-L system is just big enough to need very careful consideration of all aspects - also the sw freq is likely to be lower ( ~ 1-2kHz ) so the design of any filters is a lot more involved ... as is start up and the consideration of an active PFC front end to minimise distortion on the mains
At 10kW you can just use 6 diodes to rectify the incoming mains for the DC bus - no so much for 200kW / kVA ...
It depends. I presume that major manufacturers like Siemens have modular software that is used through different VFD sizes of a series or even across series. That's at least my impression when looking at the refernce manuals.
A software containing all functions necessary for high power inverters can surely run a low power device.
you'll find out when you go to use the smaller software in the bigger converter - mainly to do with the lower switching frequencies and the lower filter freq's in the hard ware ...