Re: Three Phase Generation and transformer

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: <davep@xxxxxxxx>


> I am nearing completion of my 3 phase 20KVA Diesel powered generator.
> Yup, Portable power! The generator is currently wired 277/480V Wye. I
> have a 480v delta to wye step down transformer which would then be
> 208/120 (with neutral). My HV supply wants to see 208v 3 phase and a
> neutral which in turn supplies 28KVDC.
>
>     * is it ok to connect the generator 480v wye (sans neutral) to
> the Delta Primary of the step down transformer?
>     * If so, how should the wye generator, delta-wye step down
> transformer, and wye HV step up transformer be grounded?
     Its been a Long time, so if anyone knows better, speak up.

     I would tie the three neutrals together:
      alternator,
      Transformer &
      HVDC supply

     and ground the lot.  If one is available, a
     current transfromer in the 'ground bus', would be
     instructive, should read zero  If not zero, find out
     why.

     I'm thinking earth ground ~should~ be nearest the HVDC
     supply, but not real critical?

     'coil' rf ground' to be 'seperate'.

     As i say, other views welcome.

     best
      dwp