Green and clean

Solar Ćuk controller for motor home

There are some good products on market however I was one day reading the article about Slobodan Ćuk and his interesting charger project (published in 2005 Elector magazine) and made a decision to do it.

Google->Ćuk converter (Ćuk is pronounced as chook)
cuk_1

System design
The motor-home doesn't have enough area for many panels. It means that the supplied to battery power is limited. As my motor-home has 24v system the voltage is known - 24. Two 12v panels connected in paralles produce apprx. 24v.
As Ćuk converter will be used battery power to operate. It would be a good idea to connect it to this battery only during a very good sun light intensity. Probably a separate battery operated module is needed to check on it.
When Ćuk converter is On it suppose to check on the battery voltage value, PV voltage value, make a decision to connect both together if PV_v >Batt_v and after that make another decision: what charging stage to use?

Ćuk converter
The main part of this converter is L1,L2 and (if used) the isolation transformer.
Arduino can supply 30kHz PWM to Ćuk converter Mosfet(s) and by changing the Duty Cycle control the going through the Ćuk converter current.
Arduino suppose to analyze voltage and current and decide what voltage and what current to apply to 24v battery. In my design I use AGM battery and all parameters are adjusted for this type of battery.

Making
I have managed to create a 1st converter and even tested with 10 amps.
Will update more later.

Links
https://en.wikipedia.org/wiki/Cuk_converter
https://www.quora.com/What-are-the-applications-of-cuk-converters