One year ago, I began building my own solar system to provide power for my village house.Initially I made a LM317 based charge controller and an Energy meter for monitoring the system.Finally I made PWM charge controller. In April-2014 I posted my PWM solar charge controller designs on the web,it became very popular. Lots of people all over the world have built their own. So many students have made it for their college project by taking help from me.I got several mails every day from people with questions regarding hardware and software modification for different rated solar panel and battery. A very large percentage of the emails are regarding the modification of charge controller for a 12 Volt solar system.
To solve this problem I made this new version charge controller so that any one can use it without changing the hardware and software. I combine both the energy meter and charge controller in this design.
Specification of version-2 charge controller :
1.Charge controller as well energy meter
2. Automatic Battery Voltage Selection (6V/12V)
3.PWM charging algorithm with auto charge set point according to the battery voltage
4.LED indication for the state of charge and load status
5. 20x4 character LCD display for displaying voltages,current,power,energy and temperature.
7.Reverse current flow protection
8.Short Circuit and Over load protection
9. Temperature Compensation for Charging
Electrical specifications :
1.Rated Voltage= 6v /12V
2.Maximum current = 10A
3.Maximum load current =10A
4. Open Circuit Voltage = 8-11V for 6V system /15 -25V for 12V system
Full Project is on Instructables