Step Up transformer Neutral Circulating Current

[abrahamespinal9]

Greetings,

I have a solar PV installation with an issue.

Is a PV installation where the System is 208V and im using a Y-Y transformer for getting 480VY for the solar PV inverters.

The issue is that when i connect the 480VY/208VY transformer i get a circulating current from the phase 3 and neutral of this transformer to the neutral of the distributión transformer of the client 12470Y/208Y. Is there a particulary reason for this? What could be a solution?

Please help me with this topic.

 

[electrofelon]

I thank you need to be more specific about the transformer connections. Are the two y points connected together or isolated? Did you ground anything? where are you seeing the circulating current exactly? On what conductor? how do you know there a circulating current did you put a amp clamp on it?

 

[pv_n00b]

When you connect a WYE with a solidly grounded neutral to the service it becomes a source of ground current to the utility, so any imbalance in the utility distribution system can use the grounded neutral as a return. This is why most transformers are delta-WYE. The only way around it is to either unground both sides of the transformer or ground the utility side through an impedance.