The inverter performance ratio indicates the ratio between the actual energy yields and theoretical energy yields of inverters.
The calculation formula is as follows: PR = EAC/ (YR×PO) x 100%.
EAC indicates the actual energy yields of inverters in a day.
(YR x PO) indicates the theoretical energy yields of inverters in the same period.
YR indicates the inverter equivalent power generation duration.
YR= H/GSTC. Unit: kW·h.
H indicates the total irradiance on the inclined plane of the PV plant array.
HT= Σtime(Hkx ε).
lΣ time indicates that the sum is calculated by recording time.
lHk indicates the Kth 5-minute increased irradiance of the current day monitored by the EMI.
ε indicates the temperature correction coefficient.
ε = 1 –(Tk– 25) x Component peak power temperature coefficient.
Tk indicates the Kth 5-minute component surface temperature monitored by the EMI.
A lot of EMI such as pyranometer does not measeure the temperature of the pv module (Tk ).
In this case to not affect the Performance Ratio formula, the temperature corection coeficient will not be calculated anymore , so ( ε =1).
