Questionable Solar
Member
- Location
- California
- Occupation
- Electrical Engineering
I am trying to understand how the DC input limit works for inverters that are being powerlimited due to the recent NEM applications. We have a few designs at our company that are being heavily affected by bifacial gain, limiting that amount of DC we are allowed to put on each of the inverters. One solution I had in mind was to take larger nameplate inverters (i.e. taking a SMA 50kW and upsizing to an SMA 62kW for example) and powerlimit them down to the correct AC size the original design has (taking the SMA 62kW and powerlimiting its AC output to 50.0kW).
The problem I need cleared up is this: if each of the inverters have a specific ratio of tolerance at the base nameplate AC output (i.e. the SMA 50kW having a max DC input of 75kW, making the DC to AC ratio 1.5) then is that ratio proportional to whatever new AC rating we powerlimit to (going from 50kW to 40kW, and the new DC input being 60kW DC due to the 1.5 DC to AC ratio) or is the DC input rating the same for the inverter no matter the AC output we are powerlimiting to? I believe I am overthinking this, but want to make sure this is a viable solution before presenting this option. Link to SMA Core1 inverters.
The problem I need cleared up is this: if each of the inverters have a specific ratio of tolerance at the base nameplate AC output (i.e. the SMA 50kW having a max DC input of 75kW, making the DC to AC ratio 1.5) then is that ratio proportional to whatever new AC rating we powerlimit to (going from 50kW to 40kW, and the new DC input being 60kW DC due to the 1.5 DC to AC ratio) or is the DC input rating the same for the inverter no matter the AC output we are powerlimiting to? I believe I am overthinking this, but want to make sure this is a viable solution before presenting this option. Link to SMA Core1 inverters.