This was one of the final projects I completed during my exchange program in Finland.
For this project, I collaborated with Fatbardh.
This is a much larger and more advanced version of one of my first projects ever.
Also a solar tracker: http://www.instructables.com/id/Arduino-Solar-Tracker/ .
The features of this solar tracker are:
- Solar tracking involves ensuring that the solar panels stay oriented toward the sun for as much time as they can.
- Electricity checker: It monitors the voltage and current produced by the panels and computes the generated Power and Energy.
- Data logging involves transferring the data recorded by the energy monitor to ThingSpeak’s cloud platform.
- Additionally, there is an LCD screen to show the data from the energy monitor.
This instructable contains technical illustrations of the project. A link to the full project report and presentation is available at step 10.
Why:
To read more about the energy profit from this kind of system please read this chapter on wikipedia.
This is also my entry for the 3D printing contest:
I would be thrilled to own a 3D printer. Doing other projects will be greatly beneficial for me. To create gears and protective covers. If you enjoyed this Instructable, please consider voting for it in the 3D printing contest.
My excuses for my spelling mistakes, you may always let me know if you see some.
Step 1: Overview
In this step, I’ll go over all the used components in this project.
Solar panels:
We used 2 solar panels of each 12V 150W which will bring the total to 300W.
Energy Monitor: The energy monitor uses 2 current sensors, to measure the current.
Using a voltage divider to reduce the voltage to a level that can be read by the Arduino’s ADC.
If you don’t want to make it yourself self you can buy one as well: ebay link
Light direction sensor:
Light direction is detected by four Light-dependent resistors or LDRs. Each of the LDRs is placed in a voltage divider and the signal is fed to the Arduino its ADC.
ebay link
The end-stop Switch
The end stop makes sure the mechanical construction doesn’t collide in itself.
The motors
The motors are 12V linear actuators from internet.
And are controlled with a very simple H-bridge.
ESP8266
The ESP8266 is a cheap WIFI module that we use to send the data to a ThingSpeak datastream
The LCD
The display is used to display the energy monitor values
The microcontroller
The microcontroller we used was an Arduino ATMEGA 2560
Arduino MEGA 2560 R3 ~10$ – Ebay
The charger
For the charger, you should search for an MPPT (max power point tracking) charger. And for sure not buy the one in the picture because this one overcharged our batteries and is not MPPT.
Step 2: Mechanical Construction.
Neither of us had much experience with metalworking. As a result, we received assistance from a nearby vocational school.
The structure includes a sturdy steel beam with a separate section that is inserted by sliding a rod into a hole. We add levers to this arrangement which we attach the linear actuators to.
Take a glance at the PDF technical drawings and photos to gain a clearer understanding of its appearance.
Fusion 360 is used to create both the technical drawings and the renderings.
Step 3: The Light Sensor
This is the same principle as the previous version. 4 LDRs separated by a crossbeam. This time the crossbeam was 3d printed.
It works by comparing the average LDR values of each side to determine which side to rotate to.
LDR holder 3d model: http://www.thingiverse.com/thing:1500571
Step 4: Motor Control Algorithm
The function of the motor control algorithm is to activate and deactivate the motors. Everything hinges on the information gathered by the light sensor.
This has also shown enhancement in comparison to my previous iteration. A hysteresis is now in place. Similar to a Schmitt trigger. The motor will only activate if the light difference exceeds a specific threshold, and it will only deactivate if the light difference is below a certain value.
Step 5: Energy Monitoring
The energy monitor works by measuring the voltage and current output of the panels.
By multiplying these two values you get the generated power.
P = U * I
P= Power in Watt; U = Voltage in Volt; I = Current in Ampere.
By integrating the Power over time you’ll get the total generated Power.
Voltage measurement
The voltage measurement is done by a voltage divider over the panel’s output. To get the output range of the panels 0-22V down to a range of 0-5V to protect the analog-digital-converter.
Current measurement
The current measurement is done by two ACS712 hall effect current sensors.
Step 6: Data Logging
The data logging is done by sending all the data to a ThingSpeak channel.
This is done by an ESP8266 WIFI module.
Step 7: Microcontroller
You can get an Arduino MEGA 2560 clone on ebay for somewhere in-between 5$-15$
Step 8: Software
If you want to use this code you should have a look at:
- EnergyMonConnections.h
- connections for the energy measurement
- solartrackerdefines.h
- settings and connections for the LDRs and solar tracker
- solarPanel.h
- to set the formulas right for the calculations of the ADC
- Internet.h
- set wifi name and password as well as API key
Step 9: Final Results!
Step 10: More Information
For much more information about this project.
I would like to recommend you my project report and presentation.
Step 11: Questions
Feel free to ask if you have any questions. If you are unable to locate the answer in the comment section. I’ll aim to include additional details in the Instructable based on the areas that receive the most questions.
I hope you had fun reading my Instructable.
