Solar array inverter to run as island
Solar array inverter to run as island
(OP)
Hello,
I'm working with an enphase inverter, intended for PV arrays for grid tie applications. The inverter needs to see the proper grid voltage and frequency for some time before it will come on line. For testing purposes (and safety), I would like to create a simulated grid to which I would connect the inverter. The inverter is designed to push out as much current as the attached PV array can supply.
I have considered 2 methods so far: 1 is to use another inverter tied to a battery bank. The inverter would produce a 120V sine wave for the enphase inverter to synch with. The problem with this is that the enphase inverter is likely to backfeed the other inverter, which would destroy it.
Method 2 is to use a generator. This would work but it would be loud and expensive. And there is still the problem of backfeeding, which would destroy the generator.
Does anyone have any experience in doing this? Any ideas?
thanks
I'm working with an enphase inverter, intended for PV arrays for grid tie applications. The inverter needs to see the proper grid voltage and frequency for some time before it will come on line. For testing purposes (and safety), I would like to create a simulated grid to which I would connect the inverter. The inverter is designed to push out as much current as the attached PV array can supply.
I have considered 2 methods so far: 1 is to use another inverter tied to a battery bank. The inverter would produce a 120V sine wave for the enphase inverter to synch with. The problem with this is that the enphase inverter is likely to backfeed the other inverter, which would destroy it.
Method 2 is to use a generator. This would work but it would be loud and expensive. And there is still the problem of backfeeding, which would destroy the generator.
Does anyone have any experience in doing this? Any ideas?
thanks





RE: Solar array inverter to run as island
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RE: Solar array inverter to run as island
But why? The the testing labs have gone through all of this stuff already.
RE: Solar array inverter to run as island
RE: Solar array inverter to run as island
That is an excellent suggestion. I will do that.
thanks
RE: Solar array inverter to run as island
That said; I would look for a generator and a resistive load bank that is a little larger than the invertor that you want to test. Start the generator and connect the load bank. Then connect your invertor. The heavy resistive load should give you stability and absorb a lot of the harmonics. The output of the invertor should supply the load bank and reduce the load on the generator (and the fuel costs).
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Solar array inverter to run as island
RE: Solar array inverter to run as island
RE: Solar array inverter to run as island
RE: Solar array inverter to run as island
RE: Solar array inverter to run as island
Fuel consumption will be reduced when the panels are supplying power. You may be able to switch off most of the load during the night.
Whatever you are most comfortable will probably be the best solution.
If you go the VFD route, the VFD should be capable of regenerating or you will need a load bank. You may be able to load the DC bus when the voltage goes high, but wait for an opinion from one of the VFD experts on this.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Solar array inverter to run as island
RE: Solar array inverter to run as island
That is why we suggest a load bank and a generator. The load bank takes a fairly constant load. As the inverter supplies power, the load on the generator becomes less. The inverter is capable of running a little above or below rated frequency and it should be possible to locate a generator capable of running within the inverter limits.
Bill
--------------------
"Why not the best?"
Jimmy Carter