Grid assisted UPS system

Using Arduino Project Guidance
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The Title of this is just buzzwords that are involved in this project.

I have just began to get into using arduino and have put together a few little circuits using it. It's amazing what it can do!!! :o

I'm looking into a system that offers an AC uninterrupted power supply as an output.

It's main input will be from both a wind turbine and a few solar panels (There also could be a generator involved yet). I'm thinking about a 2 kW wind turbine and 1 kW from solar. Both go through a charge controller to feed batteries or to a dump when the batteries are fully charged.

Usually batteries would then be connected to a DC to AC inverter. However, there isn't a guarantee that there will be a constant supply of electricity to the inverter seeing as though solar only provides energy for daylight hours and the wind turbine will only supply when there is wind. The batteries would keep the inverter going for a while but would go dead pretty quick if there was a requirement of up to 2 kW!

I'm thinking the solution for this would be to have a grid assisted UPS. A system that would switch over to mains supply when the batteries began to drain of there energy.

Basically, I want to use an Arduino and set it up so that it can activate a relay possibly to switch to mains(???). I have seen ATS switches but it's not exactly what I'm looking for. Arduino is a lot more fun and there is a lot more learned from using arduino. :smiley:

Although, then there is the problem of that split second when the coil in the relay switches over causing a short period of no power being provided. Perhaps a basic UPS that is used with computers could deal with that sudden dip? (generation>charge controller>batteries>Inverter>(relay with option of grid mains controlled by micro-controller)>UPS> computer, monitor, laptops etc.

I'd also like to use the arduino to monitor wind speed, lux levels and as an energy meter but i'm not looking for that info here as it is elsewhere in the forums.

Have any of you come across a similar project?

Has anyone anything to add to this or have any experience with something similar to this?

Any information shared on this would be greatly appreciated!!

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Why not have the Arduino switch on a mains-powered battery charger. That way you don't have the switch-over glitch.

Turn it on for, say, an hour when the battery voltage gets low. Give the batteries a minute on their own and then start checking the battery voltage again. Repeat whenever the battery voltage is below the desired limit. That will prop up the battery for times when solar and wind aren't keeping them charged.

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Thanks for the reply! That would work but it's not really the way I was hoping to go about doing this. This project I'm working on will apply to future projects I'm hoping to build with this similar concept.

The other thing is that I don't have a battery charger, only a few UPS's.

I was thinking maybe if I had an analogue input going into the arduino from a sensor detecting the voltage in the battery. Then I could programme the arduino to activate a relay when the voltage was low to switch to the mains supply (Battery low). Therefore that would give preference to the solar panel or wind turbine as the prime source of power.

Not sure though how I would be able measure the voltage coming from the battery :roll_eyes: