Secondary Network Distribution Systems Background and Issues ......

[Open Neutral]

So a friend that works on rooftop solar issues in DC, and bigger farms outside of there, was telling me about distribution being fed from multiple sources.

I said "Huh???" and he referred me to Secondary Network Distribution Systems Background and Issues Related to the Interconnection of Distributed Resources

Needless to say, it's news to me.

He sees both individual customers (?buildings?) and neighborhoods fed this way.

This creates problems err opportunities[1] for his folks deploying grid-tie solar. The reverse power protection (designed to prevent re-feeding tripped Primary 1 from Primary 2 via Transformer 2, secondary, then Transformer 1) can't cope well with solar input mid-span.




[1] al-la Curtis LeMay

 

[don_resqcapt19]

Very common method of power distribution in downtown areas of larger cities...often having available fault current well over 100,000 amps.

 

[Open Neutral]

Not surprised that there's Yet Another thing out there I've never heard of before.

But a fault still takes down that secondary, regardless of how many feeds it has; except I suppose if it's a vegetation fault that available current level soon solves it.

 

[Paulsey88]

As Don said, quite common in dense urban areas. Very stiff supply, very reliable, high fault currents available. Usually placed in "conduit & manhole" systems where most facilities are underground. While very reliable, transient events can cascade through the system if not properly protected and planned for (see recent events in NY, NY). I would not want to be the engineer integrating variable distributed generation.