Hi there,
First-time poster here, and an electronics amateur with what is probably a very basic question, so I'm not even sure I'm in the right place...!
I have a small device that uses power from a solar panal to run a small motor for a pump. The device also has a single-cell battery to store power to run the motor while the sun's gone. I've had a look at the wiring inside and it's very simple - I've knocked up a circuit diagram which is attached.
There is one problem, however. Because the load on the motor is a reciprocating pump it has uneven rotational load on the motor, making it hard for the motor to start. Frequently, therefore, the device will take some time start as the motor will be stalled trying to overcome the initial resistance. However, even in dim light, if you manually start the motor (overcoming the initial resistance) it will run fine.
So, my question is this: is there a simple way to modify this circuit so as to charge up a capacitor from the solar panel that would be able to release a burst of charge to 'kick-start' the motor? I know capacitors can do this sort of thing, but I'm racking my brains back to school days and not getting very far!
The solar panel is about 6"x4" and is probably a 3-5v rated panel. The cell in a single (1.2v) NI-MH D size. The motor is a small (<1" diameter) thing like you used to use at school. Not sure what voltage rating it is, though.
Many thanks,
Andrew