I agree, RRaghunath,that the 480 Volt does not need to be grounded under some codes, including the code that I am subject to..
However grounding the 480 Volt system avoids over-voltages due to discontinuous ground faults and inadvertent common mode over-voltages due to accidental contact between a 480 Volt phase conductor and higher voltages.
In the absence of a neutral the 480 volt system may be corner grounded or if a 240:480 Volt transformer is used, the center tap may be grounded.
The wye:delta arrangement may have issues with circulating currents and with back-feeding into lost phases.
Changing to a delta wye transformer avoids the wye:delta issues and provides a neutral for system grounding.
Although the 480 Volt system does not need to be grounded grounding the 480 Volt system is highly recommended.
I note that the OP's original question concerned running a neutral conductor with the overhead.
We are in agreement that there is no need for a neutral to be run with the 22kV circuit conductors.
Interestingly, the utility that supplies my residence does not run neutrals for single phase distribution circuits. One wire only.
There is many miles of single wire, single phase distribution in rural areas.
At each service transformer, the neutral side of the transformer is grounded with a driven ground rod. A neutral conductor is carried overhead for one span and grounded a second time with a driven ground rod. End of story, end of neutral conductor.
I was quite taken aback when I moved to this area 10 years ago. The practice is widespread and I have never heard of an issue or accident attributed to the lack of a neutral conductor.
If it stops snowing I may be able to get a picture but no promise.
Bill
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"Why not the best?"
Jimmy Carter