Low ripple 220V DC power supply for peltier elements in series

My project is a peltier based cooler that is using 16 5A peltier elements to cool a device super fast, and the remaining challenge is the power supply. The voltage for each element should be between 12 and 15V. Slow variations in the voltage is not a problem, but the ripple should be low.

A 90A/15V power supply could be used, but these are expensive and space is very limited.

What I'm thinking of is embedding a simple 220V DC power supply with a diode bridge and a ripple filter, and connect the peltier elements in series. Peltiers in series is not a problem, but will it be possible to get rid of the ripple on such a high voltage?

Should there be one filter for all elements and/or seperate filters for each element?

Why is ripple so important? Peltier devices don't need a particularly 'clean' power source.

Brian.

You will get slightly higher performance with constant current operation of peltier elements. In a first order estimation, the heat pumping capacity will be set by the average current and the internally dissipated power by the RMS current. The peltier characteristic can be imagined as mostly resistive with a small temparature dependent e.m.f part. In so far even unfiltered full wave rectified mains voltage won't perform so bad, with may be 12 to 15 % less efficiency.

Hjallmar said:

My project is a peltier based cooler that is using 16 5A peltier elements to cool a device super fast, and the remaining challenge is the power supply. The voltage for each element should be between 12 and 15V. Slow variations in the voltage is not a problem, but the ripple should be low.

A 90A/15V power supply could be used, but these are expensive and space is very limited.

What I'm thinking of is embedding a simple 220V DC power supply with a diode bridge and a ripple filter, and connect the peltier elements in series. Peltiers in series is not a problem, but will it be possible to get rid of the ripple on such a high voltage?

Should there be one filter for all elements and/or seperate filters for each element?

Click to expand...

Hi Hjallmar, and welcome to EDABoard forum,


What is DC voltage after rectifying 220V AC ?

I will first check maximum allowed voltage for peltiers.

What will happen if one or more peltiers become damaged (in content of serial connections) ?

What is complete cooling area which is obtained with Peltier elemets areas ? Do you need that big area or you plan to use Peltiers in termal cascade ?


For me whole design is not good and dangerous. All cost will be high and in my country there is proverb "Skuplja Dara nego maslo." (Dara is woman who makes butter, and Dara is more expensive than butter). :smile:

Look to use some better solution, water cooling, increase heatsink area, add fans,.... 15V @ 90A its around 1,4KW for cooling I dont know what you try to cooldown but with this power rate you can use cryogenic cooling system.

I think as first step for hard cooling needs is closed water cooling system. But all depends from what you need, what you want and what you can.



Best regards,
Peter

:wink: