Home Assistant Solar Tracker

For the final PCB Design, I am adding a Spark gap and Zener diodes for input protection.

On the prototype, I am currently using two relays to turn the motor on. In the final design, only one relay will be used to reverse the motor direction, since this relay is used only twice a day it should last forever.

The movement relay is being replaced by a PCB solid state relay.

The logic power supply is also being replaced from a charger adaptor to a Meanwell power supply module soldered on the PCB.

I created a project repository for the source code and future PCB design.

https://github.com/VinisLab/SolarTracker

All project is under MIT License.

On the chart bellow you can see our best generation day, without any clouds, before installing the tracker:

The generation was 14,22kWh.

On the second chart the results are with active tracking, some clouds happened so we expect even better results:

The generation was 16,41kWh.

When the sun is in the extreme positions one panel can generate shadows in the adjacent one.

For this reason I added a logic that calculates the shadow incidence based on our assembly and sun position.

On this Grafana chart you can observe the green light being the sun position referenced to the installation position, this angle is converted from the sun's azimuth and elevation.

The yellow light is the shadow compensation curve.

The plateau observed between the two different curves in the blue line is caused because the travel limit.

The blue line tracks with 2 degrees of error the sun position, this data comes directly from the accelerometer and is used by the motion control.

The result is quite good since the motor is not using an inverter and only uses relays to start and stop.

The system is fully functional.

The next phase will be to substitute my prototype PCB with a proper design for the solar tracker.