amundsen:
I understand it is not possible to regulate both current and voltage, but my concern is indeed more to limit the current because of the nature of the panel it might change according to time.
Well a panel may decrease in it's maximum current capacity in time, especially if you don't clean it off once in awhile, however I can't think of how it could increase it's maximum current capacity in time unless you happen to move to a location that has more sunlight? Why wouldn't a simple fuse be a good current limiter? Keep in mind that the load generally determines how much maximum current will flow not the panel even when the panel is producing it's maximum voltage.
Again the better you can explain your requirements and application, the better the quality of the possible answers might be.
Lefty