Forgive me for being unclear. The low-voltage side being supplied by the DER is 480 volt and is a grounded Wye. The high voltage side is 13.8kV and is in a Delta configuration and is connected to customer-owned MV gear (also being supplied by utility MV distribution lines). So "primary" and...
I am currently designing an inverter based distributed energy resource facility in which, upon review, the utility is requiring an additional zero sequence current for effective grounding on the high-voltage side of my transformer. I have a 1500kVA oil-filled padmount step-up transformer...
