Hi Everyone like most new members I'm here seeking help.

[JohnHaine]

Quite a lot to unpack here.

First, with some rewiring everything except the spindle motor should be able to run directly from the mains, without using the step-down transformer.

The spindle needs ~6kW to run, or ~24A max, which you won't get from a standard ring main (which I think is limited to 16A). However in the UK a cooker spur (also electric shower?) can run up to 32A or ~8kW, so plenty at least from a power p.o.v.

The phase converter you linked to seems to convert from 230 single phase to 380V 3ph so should run your motor directly. However you don't get the benefit of variable speed which presumably you do with the VFD. I am not sure if it would be recommended to connect the output of such a phase converter to a VFD input, you would need to check with the phase converter manufacturer.

A small amount of googling suggests that one way to work an inverter (such as your VFD) is using an external DC source derived from a single-phase supply. Looking at the manual for the HLP-... it seems to have a connection to the internal DC bus voltage brought out to terminals. However it is not obvious whether this is rated for use as a supply input, again you would need to check with HOLIP. The idea is to use a beefy external supply which transforms 230V to 380V (transformer), then a bridge rectifier to convert to DC, plus some smoothing capacitors. Basically you bypass the internal 3-phase bridge rectifiers of the VFD. You would need to seek specialist advice from the VFD supplier to check this out - it certainly isn't DIY electrical engineering.

Or look for a single phase input 7kW VFD and convert the motor to delta to run off 230V 3-phase? Replace the current HLP inverter.