Calibration in PV model

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Suraj Bhanu Jat

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Apr 18, 2023, 9:42:08 AM4/18/23
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Hello,

I have actual power output data from a solar powerplant for 04-04-2023 with time stamp of 5 minutes. I have prepared the physical model using PVlib and calculated the power output from physical model and then compared it with the actual AC power output. 

specifications of PV plant  - https://pvoutput.org/display.jsp?sid=46137


Now, the problem is that there is huge difference between actual power output and physical power output. Can anyone please help me witht the physical model. What should be calibrated in the physical model so that I can reduce the difference between the actual power output and the physical model power output.

I am attaching the physical model code as well as the excel file in which I have compared the results. Weather data I have extracted from PVGIS.

Thanks in advance,
Suraj Jat


 
Physical Model.pdf
04-04-2023.xlsx

kevina...@gmail.com

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Apr 19, 2023, 8:10:31 AM4/19/23
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Hi Suraj,

Based on the plot in the excel file, I suspect that the solar position is being calculated incorrectly.  Looking at the GHI data, sunrise seems to be around hour=7 and sunset around hour=19, which means the timestamps in this dataset are probably in local time.  But the notebook is localizing the input data to UTC.  That would cause a time shift of several hours between the calculated solar position and the irradiance data, causing an asymmetrical and strange power output like in your plot.  Try setting the correct time zone for your data and seeing how that improves things.

Best,
Kevin
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