Voltage regulator to charge battery

26^th Feb 2013

Week Four Sem. 2:

 Due to a technical “hitch” the schematic diagram has been delayed, the 28pin DIL and 3 pin resonator are not available on Cadstar and have to be drawn and placed onto the ECAD libraries. Further investigation has taken place into incorporating a regulator to supply power to a battery and prevent over charging by cutting off the charge to the battery when fully charged. initial circuits that could be used involve the LM 317 adjustable voltage regulator however this has a drop out voltage of about 3 volts which:

1. is way to high as there is not enough margin on the panel for this.
2. is very wasteful.

Battery regulator circuit

As there are still analogue pins available on the Arduino a schematic for a solar shunt could possibly be adapted to suit this purpose.

instead of the comparator an analogue pin on the Arduino used with a voltage divider set to the batteries maximum charge voltage and software to activate /deactivate the darlington pair.

 Preliminary measurements have been taken and dimensions drawn out for the supporting stand and mountings for the panel and the pan and tilt module from the data sheets, investigations into acquiring a light meter for testing has been done.

15^th Feb 2013

Week Three semester 2:

prototype on breadboard 

               

The Prototyped sensors.

Over the intervening period of term report handed in and other pressures the blog has not been updated  however the progress as to the electronics and prototyping to breadboard.

The sensors have been wired in series with a 22k resistor biased with 5 volts and a signal line between them to be read by the analogue pins of the Arduino. The 5 volts is supplied via a 7805 regulator which in turn is being supplied by 12 volts to simulate the panels voltage.

Two transistors are used as switches for the motor power supplies and a PWM signal line for the position of the servo.

The software has been written and the circuit and software work well together under preliminary home testing. during this coming week i hope to produce a schematic and a PCB design to begin manufacture.

 

short video of the software and hardware working.