86.4 kW Large 240V 1-Phase Integration

[MJRobinson]

Suggestions on integrating a 86.4kW PV system to a 240V 1-Phase Load Center (400A).

I was originally thinking (10) SMA 7.7's. But they add up fast $$, especially when we add an extended warranty.

I've never had this come up before but thought I would throw it up here.

Is there a 480v 3-Phase to 240V 1-Phase transformer that would do this job? In this case I would use a CORE-50 and a SMA15000

Thanks,

M

 

[ggunn]

Suggestions on integrating a 86.4kW PV system to a 240V 1-Phase Load Center (400A).

I was originally thinking (10) SMA 7.7's. But they add up fast $$, especially when we add an extended warranty.

I've never had this come up before but thought I would throw it up here.

Is there a 480v 3-Phase to 240V 1-Phase transformer that would do this job? In this case I would use a CORE-50 and a SMA15000

Thanks,

M

You cannot interconnect a three phase inverter with a single phase service by any remotely conventional means. A transformer alone won't do it. The largest single phase inverters I know of are 11.4kW.

 

[MJRobinson]

Yep

Yep

You cannot interconnect a three phase inverter with a single phase service by any remotely conventional means. A transformer alone won't do it. The largest single phase inverters I know of are 11.4kW.

What 11.4?

Michael

 

[GoldDigger]

Although there is a passive transformer configuration that can convert a three phase source to produce single phase power it does not work in the reverse direction (voltage reference on the singe phase side), so it will not do you any good. Any inverter used would be grid interactive and require a voltage waveform reference for each phase. Your question is really whether there is a transformer connection which takes single phase input and produces three phase output.

A rotary phase converter would fulfill that requirement, but would not provide enough stability and still would not allow a power flow in the reverse direction.
A motor-generator set would work in theory, but the losses would, IMHO, be far too high.

Is there no chance of getting a three phase POCO service for this purpose?

 

[ggunn]

What 11.4?

Michael

Fronius and SolarEdge both make 11.4kW single phase inverters.

 

[ggunn]

Although there is a passive transformer configuration that can convert a three phase source to produce single phase power it does not work in the reverse direction (voltage reference on the singe phase side), so it will not do you any good. Any inverter used would be grid interactive and require a voltage waveform reference for each phase. Your question is really whether there is a transformer connection which takes single phase input and produces three phase output.

A rotary phase converter would fulfill that requirement, but would not provide enough stability and still would not allow a power flow in the reverse direction.
A motor-generator set would work in theory, but the losses would, IMHO, be far too high.

Like I said...

 

[pv_n00b]

Suggestions on integrating a 86.4kW PV system to a 240V 1-Phase Load Center (400A).

I was originally thinking (10) SMA 7.7's. But they add up fast $$, especially when we add an extended warranty.

I've never had this come up before but thought I would throw it up here.

Is there a 480v 3-Phase to 240V 1-Phase transformer that would do this job? In this case I would use a CORE-50 and a SMA15000

Thanks,

M

Something you will want to look into is if you are sharing a distribution transformer with others. If you are on a shared transformer there is usually a 20kW imbalance limit allowed and your 86kW system will exceed that.

 

[PWDickerson]

Fronius makes a 15 kW single phase 240V inverter. It is the largest single phase inverter I am aware of. Five of them should do the trick.

 

[jaggedben]

The Fronius is probably the way to go, but I will just point out that the latest version of the Enphase IQ combiner would have the same output wiring.