How is mains source decided?

[DaveS]

Hi all,

Sorry if this is a dumb question.

In a typical solar installation we have a mains grid supply and a Solar Panel / inverter mains supply joined together. This combined mains supply supplies the house. If an excess of power is generated by the solar panel after supplying the house it is exported to the grid.

How does the house "know" to take it's supply from the inverter first and not the grid?

Dave.

 

[Nigel Goodwin]

It doesn't need to 'know' anything - essentially your house is just fed from a single 'supply', the actual source makes no difference.

Try thinking of it as always been fed from the grid, and your inverter as always feeding the grid.

 

[DaveS]

Yes, that works Nigel. Just something I'd never thought about before.

Thanks for that.

Dave

 

[Jules_Theone]

But what makes the power flow from the GTI inverter onto the grid, does the inverter lead the voltage or current sinewave or the voltage from the inverter is slightly (marginally) higher?

 

[Nigel Goodwin]

But what makes the power flow from the GTI inverter onto the grid, does the inverter lead the voltage or current sinewave or the voltage from the inverter is slightly (marginally) higher?

Measure the on-load and off-load output voltages from an inverter, and I suspect you will have your answer

 

[debe]

The output voltage needs to be higher than the mains for any current to flow. This also creates a problem in suburbs that have a lot of GTI solar systems, It can cause higher mains voltage.