modelling a PV invertor

[confusedengr]

thread238-299994

I am working on a solar farm project wherein it is required to model the AC side of PV inverters connected to a 415V AC board through to the 11kv Grid through a transformer. (modelling of Solar PV modules are not required).In order to find the short circuit fault contribution,how can the inverters be modelled.

I am using SKM POwertools.

Can this be modelled as a Utility source or a Usual generator?
Hvae seen a previous thread related to this;however could nt find any conclusion in that.

 

[Janitor]

Do inverters for solar farms in your area require fault ride through?

 

[confusedengr]

No fault ride through is not a requirement. However, some of the large invertors comes with built-in FRT which conflicts with the requirement of Anti-Islanding protection.

 

[IPopov]

Hi, it is not necessary to make a model for inverter. According to the manufacturar the maximum short circuit current for inverter is 5 % more than the nominal current. Tiristor system inside of the inverter not allow current more than 5 %.

 

[jfpe]

As part of the UL listing process, the inverter manufacturer must measure AC fault current and duration. You should be able to get this information from them.
-JFPE

 

[cranky108]

I do know ASPEN has a model for a fault current limited generator, which is what I use.

Caution on modeling because if the units can generate reactive current, or are limited from producing reactive current will make a difference in the negative sequence part of the model. It will show up in the contribution into ground faults because of this. I haven't seen this with inverters, but I have seen this with DVAR systems.