One big 3 phase inverter or 3 small single phase ones?

[amigo]

Hi guys,
I wonder if you know what will be better - a big 17kW three phase inverter or 3 x 6 kW single phase ones?
Are there any pros and cons and why?
Thanks in advance

 

[ian.settle1]

Hi guys,
I wander if you know what will be better - a big 17kW three phase inverter or 3 x 6 kW single phase ones?
Are there any pros and cons and why?
Thanks in advance

Next question, whats it for ?????????

 

[amigo]

Its just question is it going to be better to use a big inverter,when designing a PV plant or to go for more smaller ones?

 

[poheZ]

i would have thought that 3 single phase inverters is how to install it anyway?

 

[Markc]

It may be down to what the DNO asks for. They may require total shut down if a phase is lost which would mean the three phase inverter or they may not be worried and in that case three inverters may be better so if one is lost the other two keep generating. Three inverters will cost a bit more but I would say on a 17Kw system then there must be good scope in it to cover it.
We have done systems with three inverters but under 4kw. It was the choice of the client in the end who felt it better to in case of a problem on one system.

 

[pmac10]

3 phase will produce a superior quality dc at the rectification stage and it is this dc which will be inverted to give your variable frequency ac output, this is one important difference.

 

[amigo]

From the economic side,a 3p is cheaper to buy,but there will be more DC cables going to it and on other hand,if it goes wrong,then there will be no power generated at all.Also a kiosk will be needed to protect from rain,dust and so on,as 3p's have generally lower IP because of the cooling they require.
Single phased have higher IP,so they can be installed outside with little rain cover,and at the end of each array,which will reduce the number of 6mm2 solar cables being used,but they are more expensive.Again,if one goes wrong,the others will keep going.
I can see the MarkC point,that if one phase falls,then should be an overall shut down.
@pmac10, could you please make more clear for me what you meant in your post?I wish to get it better.
Thanks