Definition
Imp (Maximum Power Current) is the current at which a PV module produces its maximum power, at STC. Typically 0.92 × Isc. Used to verify the inverter per-MPPT current limit accommodates the parallel string count.
Key Takeaways
- Imp = current at maximum power point, at STC.
- Typically 0.92 × Isc.
- Used to verify inverter per-MPPT current limit.
- Bifacial Imp is 5–15% higher than front-only — account for it.
- Stays roughly constant with temperature; small +0.04 to +0.06 %/°C increase.
Frequently Asked Questions
5 commonly searched questions about Imp (Maximum Power Current).
What is Imp?
Maximum Power Current — the current flowing through a PV module at its maximum power point. Reported at STC on the datasheet.
Typical Imp?
9.5–13.5 A for standard modules. 13.5–17 A for bifacial high-current. Half-cell similar to full-cell.
Imp vs. Isc?
Imp = current at maximum power point. Isc = short-circuit current at V=0. Imp ≈ 0.92 × Isc typically.
Does Imp affect MPPT design?
Yes. Parallel strings × Imp must not exceed inverter per-MPPT current limit (typically 12.5–25 A).
Does bifacial increase Imp?
Yes. Bifacial Imp can be 5–15% higher than front-only Imp due to rear-side irradiance. Account for this in per-MPPT current verification.
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