For the curve, what do you recommend me?
It is necessary in principle to choose close to the actual curve of the panels P (U), to be drawn, which has nothing to do with a wind turbine with I (proportional to the light) almost independent of V = U up to U max, to see the photoelectric effect curves.
UImax decreases with luminous intensity.
P (U) is thus close to a slope line proportional to the solar light flux, up to a little before Umax, to decrease abruptly very quickly to zero, to Umax at I = 0.
This is not at all like the Windmaster 500, which does not descend and has a fixed slope regardless of wind or light.
It should look for Pmax whatever V is empty by increasing the current to P max, and measure the P (U) curve automatically in the learning phase.
Is UDC UDC empty with Preel = 0 or PDC UDC chosen?
This curve is too vague in its definition.
But the program is likely to be very different for wind turbine U = Uvide-RI and Uvide decreasing with I by braking the wind turbine and solar panels with I fixed according to U up to U max.
It is possible to try the low U slope straight possible at u max panels.
It lacks a lot of specific information.