Read this INTRO first please ..
Dear All !
Hi, Im new to this forum...
Im designing a single axis solar tracker as an engineering project. Im doing this for a manufacturer , and its going to compete with a commercially available tracker,
IF my tracker is viable, we go into mass production.After a lot of testing off course.. So, I'd like to discuss lots of things with you guys because I think there are a few very bright people here.
A little introduction about my tracker,
--> Single axis (90 degree east -west)
--> Uses a 10W solar panel as a sensor and its not connected to the other big panels..
--> Im using a linear actuator with a reed sensor , amazingly takes ~2A current at 12V for moving this mammoth 300kg load (coz of the ball screw.. )
--> The Circuit has an on-board 12V, 4.5 Ah battery that im supposed to charge the battery with as well.
--> Im using an AVR Microcontroller, ATmega8. It has 6 ADCs , an analog comparitor, PWM pins, and lots of other goodies..
The system has a 8 x 250W panels as you can see. Its hooked up to a sunny boy 1700E grid tie inverter.
--> The tracker will also have a learning capability , ie it will log data and will become more efficient as time passes by.
IF IM MISSING A TRICK SOMEWHERE , PLEASE POINT IT OUT.
The questions:
1. im measuring the 10W solar panel voltage and current, for this im using a simple shunt, the INA128 instrumentation amplifier and reading the ADC value.any bright ideas on improving this setup are most welcome ...
2. Please tell me about Solar tracking algorithms that you are aware of.. I have this idea of MPPT, i know its in the regulators.. but I think if I measure the current and voltage of the 10W panel .. and position the panels so I can get the Max power on the IV curves (ie max current and voltage value ).. That would be great.. I have also looked into other algorithms .. as well..
3. I plan to use the LMD 18200 motor driver , since my actuator's reqs are so small.. anyone know of any protective circuitry in addition with the thermal and current flags on the LMD 18200 , Plz let me know..
4. Was getting problems with counting the pulses of the reed sensor, but now I think using a Schmitt trigger OR RC filter with ADC monitoring would work..
Please remember , I dont want any hardware that I dont really want.. The circuit has to be super efficient..
5. For the battery, I want two charging stages. A simple charge.. and a float charge that I can apply with PWM. to protect the battery from overcharging, I will use a switch .. (in the high or low side, haven't decided yet.. ) . I need Ideas for the switch. The switch will remain closed for extended periods of time, I also want to apply float charge via PWM , so I think I have to use a high side P-channel MOSFET.. help needed with this one..
Thanks for reading and answering .. sorry if i missed a imp detail ..
Cheers ..
Dear All !
Hi, Im new to this forum...
Im designing a single axis solar tracker as an engineering project. Im doing this for a manufacturer , and its going to compete with a commercially available tracker,
IF my tracker is viable, we go into mass production.After a lot of testing off course.. So, I'd like to discuss lots of things with you guys because I think there are a few very bright people here.
A little introduction about my tracker,
--> Single axis (90 degree east -west)
--> Uses a 10W solar panel as a sensor and its not connected to the other big panels..
--> Im using a linear actuator with a reed sensor , amazingly takes ~2A current at 12V for moving this mammoth 300kg load (coz of the ball screw.. )
--> The Circuit has an on-board 12V, 4.5 Ah battery that im supposed to charge the battery with as well.
--> Im using an AVR Microcontroller, ATmega8. It has 6 ADCs , an analog comparitor, PWM pins, and lots of other goodies..
The system has a 8 x 250W panels as you can see. Its hooked up to a sunny boy 1700E grid tie inverter.
--> The tracker will also have a learning capability , ie it will log data and will become more efficient as time passes by.
IF IM MISSING A TRICK SOMEWHERE , PLEASE POINT IT OUT.
The questions:
1. im measuring the 10W solar panel voltage and current, for this im using a simple shunt, the INA128 instrumentation amplifier and reading the ADC value.any bright ideas on improving this setup are most welcome ...
2. Please tell me about Solar tracking algorithms that you are aware of.. I have this idea of MPPT, i know its in the regulators.. but I think if I measure the current and voltage of the 10W panel .. and position the panels so I can get the Max power on the IV curves (ie max current and voltage value ).. That would be great.. I have also looked into other algorithms .. as well..
3. I plan to use the LMD 18200 motor driver , since my actuator's reqs are so small.. anyone know of any protective circuitry in addition with the thermal and current flags on the LMD 18200 , Plz let me know..
4. Was getting problems with counting the pulses of the reed sensor, but now I think using a Schmitt trigger OR RC filter with ADC monitoring would work..
Please remember , I dont want any hardware that I dont really want.. The circuit has to be super efficient..
5. For the battery, I want two charging stages. A simple charge.. and a float charge that I can apply with PWM. to protect the battery from overcharging, I will use a switch .. (in the high or low side, haven't decided yet.. ) . I need Ideas for the switch. The switch will remain closed for extended periods of time, I also want to apply float charge via PWM , so I think I have to use a high side P-channel MOSFET.. help needed with this one..
Thanks for reading and answering .. sorry if i missed a imp detail ..
Cheers ..