Hello,
I am attempting to create a simple solar tracker using two equal solar panels hooked up to each other, positive lead to negative. The idea being the panel that obtains more light will push it's current across and drive an electric motor in the direction that best orients it with the sun. The problem arises due to the fact the panels are very small and well balanced and cannot create anywhere near the amount of power needed to drive the sort of electric motor I will be needing. Any suggestions for using these panels to control a larger supply of electricity, or somehow amplifying the current output? I have considered using relays/transistors, but am new to electronics and do not fully understand what I need.
Thanks for any help.

 

If I understand you correctly, you want to connect both panels together +to- and -to+ and which ever panel is in the sun the most will power the motor. Short answer - it won't work. Firstly, if you connect the two panels together like that, they are essentially shorting each other out so you will get nothing from the panels when they are both pointing at the sun (or 180degrees away from the sun). The protection diodes which are in series with the panels will take all the current leaving nothing to power motor. A better idea would be to use a comparator circuit to compare the voltages from each panel and a relay to connect the motor to most powerful panel. To get the required power, use a capacitor or battery to store the power in then discharge to the motor when there's enough.The motor will have short bursts of power applied to it.

 

hmm, sounds like I was going about this incorrectly. Although I should have specified that these are individual solar cells, and I do not believe they have protection diodes, although I may be wrong. I did a little research on comparators and it looks like just what I need. I also like the capacitor idea, as that may solve some of my problems with the low power output. Thanks for bearing with my poor explanation and the help!

 

If you don't have protection diodes in series with the cells, they will cook each other. The diode in solar panels stops reverse current destroying the panels at night. I would connect the panels in series to get a higher useful voltage, as long as both panels are pointing in the general direction of the sun it will be ok. Do you know what voltage you have available for each cell? I've seen comparators which go as low as 2.5 - 3.0v. Also I didn't ask how powerful the motor you were planning to use is and how large the array you wanted to move?

 

I was under the impression that the diodes were in place so that that batteries being charged by panels don't drain at night or when in the shade, I wasn't aware that the panels would actually be able to do damage to each other. If I understand what you're saying, I should hook the panels up so that they may achieve the necessary power to drive the motor. My real intention with the panels was to use them as a sensor for the sun, or were you talking about hooking up the two panels in series to the comparator?
YouTube - Simple DIY Solar Tracker
This is very similar to what I am trying to achieve, except I hope to do so on a larger scale through somehow allowing the panels to open or close a larger supply of electricity. I believe the cells can output approximately 3v-4v each. I'm not entirely sure how large a motor I will be using, but I think that it will be well beyond the output of just a few of these panels.
Thanks again

 

may be im late to read this thread and reply, but if your idea is to use this to control power to a large circuit then the intensity of the light available would be enough, you can use a omni directional LDR for this with some electronics.
if you ned to move a solar panel always facing the sun, use two sensors of LDR togethr with some opamp to control a motor to move your panel, then the panel can give you maximum power.

as some one sugested, when you drive the motor, the voltage drop will disturbed your comparator input and it will start to oscilate.

razeen