I have to do a project on MPPT (Perturb & observe) with a buck converter. I've read a lot of papers on it but I'm unable to understand a few things about it. I understand that in P&O algorithms, the voltage of the PV array is varied until MPPT is reached. But how is the voltage of the PV changed in the first place? Isn't it dependent on the sun entirely? I'm not sure on this but I think that is to be done with the help of a dc to dc converter. If that is so, then it is on the output of the dc to dc converter that MPPT should be applied. But in all the papers I've seen so far, the MPPT mechanism takes input directly from the PV module and then adjusts converter voltage. I don't understand the former step of the process. I mean, it is the converter's voltage that we should be playing around with to find the max power point, not the PV's direct output as we can't even change that. So shouldn't the MPPT mechanism read and compare the converter's current and previous power levels rather than using the PV's output readings directly? I doubt I'm explaining myself very well, but I hope you understand me. Thank you!