Summary of TRACKING MAXIMUM POWER POINT FOR SOLAR EFFICIENCY
Parts used in the Open Source MPPT Project:
- ESP32 microcontroller
- Synchronous buck conversion circuit
- Switch-mode power supply (SMPS)
- Inductor cores
- Battery configuration support software
In days of yore when solar panels weren’t dirt cheap, many people (and even large energy companies) used solar trackers to ensure their panels were always physically pointed at the sun to make sure they harvested every watt of energy possible. Since the price of panels has plummeted, though, it’s not economical to install complex machines to track the sun anymore. But all solar farms still track something else, called the Maximum Power Point (MPP), which ensures that even stationary panels are optimized for power production.
While small MPP trackers (MPPT) are available in solar charge controllers in the $200 range that are quite capable for small off-grid setups, [ASCAS] aka [TechBuilder] decided to roll out an open source version with a much lower price tag since most of the costs of these units are in R&D rather than in the actual components themselves. To that end, the methods that he uses for his MPPT are essentially the same as any commercial unit, known as synchronous buck conversion. This uses a specially configured switch-mode power supply (SMPS) in order to match the power output of the panels to the best power point for any given set of conditions extremely rapidly. It even works on many different battery configurations and chemistries, all configurable in software.
This build is incredibly extensive and goes deep into electrical theory and design choices. One design choice of note is the use of an ESP32 over an Arduino due to the higher resolution available when doing analog to digital conversion. There’s even a lengthy lecture on inductor core designs, and of course everything on this project is open source. We have also seen the ESP32 put to work with MPPT before, although in a slightly less refined but still intriguing way.
Thanks to [Sofia] for the tip!
Source: TRACKING MAXIMUM POWER POINT FOR SOLAR EFFICIENCY
- Why did the author build an open source MPPT tracker?
To create a version with a much lower price tag since commercial costs are mostly in R&D. - What conversion method does this project use?
The project uses synchronous buck conversion to match panel output to the best power point. - Why was an ESP32 chosen over an Arduino for this build?
An ESP32 was selected because it offers higher resolution for analog to digital conversion. - Can this system work with different battery types?
Yes, it works on many different battery configurations and chemistries via software configuration. - Is the design of this project open source?
Yes, everything regarding the project is open source. - Does the article mention any specific theoretical topics covered?
The build includes a lengthy lecture on inductor core designs and electrical theory. - How does the project handle varying conditions?
It matches power output to the best power point extremely rapidly under any given set of conditions.
