the last graph P vs I , for the x-axis, insteads of I L, suppose to be I sc i think. and The middle point is I L max at which I sc provides enough current to go through the diode.
may be this a sptupid question but anyways i'll go for it. since diode is a sigle piece component why is current source in parallel and not in series to the diode?!
My understanding is this helps create a simple model for simulation, and the diode and its current during irradiance does not make sense in the real world, since with no load there is no actual current flowing anywhere (other than the leakage current of the PIN device): If I was to create an equivalent model, it would be far more complex !
What are the relationships like between irradiance and Isc and Voc? I've heard irradiance vs Voc is nonlinear and irradiance vs Isc is linear, but I'm struggling to get a straight answer on this
From my understanding, Voc and irradiance don't really have a relationship. It doesn't matter how many photons are hitting the photovoltaic cell and delocalising electrons per unit time (that is, assuming that the photons have an energy greater than the work function of the material they are delocalising the electrons from). Eventually, enough electrons will gather at the N-type layer, and enough electron holes will gather at the P-type layer to form an electric field that will attract the holes and electrons back together again. At that point, the delocalised electrons and holes will flow away from the depletion region as fast as other electrons and holes will flow back towards it. Once they reach the depletion region, the holes and electrons recombine. What you end up with is a roughly constant amount of holes and electrons gathered on the P and N-type layers, across which you have your potential difference Voc. It's not relevant at what rate electrons are being delocalised and flowing away from the depletion region, this will just be balanced by the electrons flowing back to the depletion region at a higher rate. As for Isc, I don't know.
I keep seeing this simple model all over the Internet....why is that? Does everyone copy and assume that is all there is to the subject? I subbed just in case you are going to flesh this out with a more realistic model.....looking....looking.....
The reason it's all over the internet is that it's a quite accurate model. The main thing it's missing is the series resistance of the wires connecting the solar cell to the outside world, as well as the shunt resistance of the solar cell itself. Also, if you have a solar *panel* and not a single solar *cell*, you will stack a bunch of these in series. Hope that helps.
@@JordanEdmundsEECS Thank you so much for this wonderful explanation! can you please add a video including the series and shunt resistance? if you could explain how the shunt resistance affects the Voc, it would be amazing! your video is one of the clearest I have seen on this subject, and only this part is missing. Thanks again!