1000w smps based on LUDO3232

Silvio

Active member
Finally I designed and etched the PCB after a lot of hard work, Here are a few pics of my progress on this 1000w smps based on Ludo schematic with some alterations and design. I will test it as soon I receive the output caps from aliexpress.

IMG_0336[1].JPGIMG_0337[1].jpgIMG_0351[1].JPGIMG_0357[1].jpgIMG_0356[1].JPG
 
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lucas-nld

New member
Very nice work Silvio, it's looking good, and the black silk screen printed on the other side of your PCB where are the parts should go is also a very nice touch! It does look like quite a waste of the transformer though, looking at how little windings there are on the transformer. That's an ETD49, correct? I'm also busy with designing a 1KW SMPS, though I'm still deciding whether it will be a half or a full bridge. However, I'll be using either an E42/50 with Ferroxcube 3C90 ferrite, or more likely even an ETD39 with 3C95. I'll be using copper tape, to maximise the transformer efficiency.
 

Silvio

Active member
Hi Lucas I used litz wire to wind my transformer with 70 strands of 0.16mm for primary and 60 strands of 0.16mm for secondary. The winding fill was around 7/8 and not much space was left though. I also included a Faraday screen in it to suppress interference as much as possible. I began my initial tests and its working quite well. I am finishing my Mains isolator power source so that I can give it a good load and establish the snubber network, check and set the short circuit protection. BTW my smps is for 80-0-80 volts out at 235vac input.
Copper tape seems better though giving maximum coupling between windings. Be careful with insulation though not too much and not too little. It is good practice that the copper foil will be a little less than the bobbin width say 2 or 3mm, but the insulation tape will be the full width of the bobbin. This will help with better insulation and less creapage voltages along the edges of the winding foil.
I will be glad to see your progress with some pics when you start your project.

Best regards and good luck

Silvio
 

Silvio

Active member
Here are a few pics of my progress on the isolating transformer for SMPS testing. This is capable of around a KW or more at 220volts out. This was taken out of an old amplifier capable of 3kw output. I am fitting it in an old UPS box. Probbably this will power my whole workbench in the future.
My progress so far I have to continue today and try to finish it

IMG_0369[1].JPGIMG_0368[1].JPGIMG_0367[1].JPGIMG_0366[1].JPG
 

lucas-nld

New member
Ah, okey, I can see in the later pictures that you did indeed fill up almost all the winding space. I thought that the pictures in your first post in this thread was showing all the windings you put on it, so that was my mistake! An isolating transformer is definitely a very useful bit of kit when building any offline SMPS. I'll be using an USB oscilloscope connected to a laptop which doesn't have a grounded plug, so that should take care of the problem for me, as an oscilloscope is pretty much essential, especially when you're making a high powered SMPS off of your own design instead of someone else's. I'll post any pictures as soon as I start with my 1KW project.
 

Silvio

Active member
Hi Lucas, I made my first test today though I did not receive the output caps and had only a couple of 470uf at 200v that I put on temporarily. I adjusted the ringing and fitted the snubbers on the drain source of the switching fets. I did some experimentation with different values and found the best combination with the smps loaded at around 400 watts. I managed to get around 1100watts out of it with resistive loads attached to the output. Load was 9 amp at 122 volts. However the output of the isolation trafo is rated at 200 volts and and not 220 as I first taught it is. I guess I have to add a few turns to it to get 220 at least. My set up was with and isolated oscilloscope and with the isolation power transformer. I still have to try it on mains. My output voltage is calculated at 78-0-78 with 230 volts input. getting within the ripple at load I guess it will sag to about 130-140 volts on full load. I also adjusted the over current protection and I set it to cut at 10amp load. This works very good and Ludo made a good job here in design. I am posting my schematic so that you can take a look on what I have worked on.

shcematic.jpg Go to next page this pic is too small to see
 
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Silvio

Active member
Hi Lucas, I made my first test today though I did not receive the output caps and had only a couple of 470uf at 200v that I put on temporarily. I adjusted the ringing and fitted the snubbers on the drain source of the switching fets. I did some experimentation with different values and found the best combination with the smps loaded at around 400 watts. I managed to get around 1100watts out of it with resistive loads attached to the output. Load was 9 amp at 122 volts. However the output of the isolation trafo is rated at 200 volts and and not 220 as I first taught it is. I guess I have to add a few turns to it to get 220 at least. My set up was with and isolated oscilloscope and with the isolation power transformer. I still have to try it on mains. My output voltage is calculated at 78-0-78 with 230 volts input. getting within the ripple at load I guess it will sag to about 130-140 volts on full load. I also adjusted the over current protection and made it work on 10 amp load


View attachment Schematic 1000w.pdf
 

Silvio

Active member
1000 watt SMPS based on LUDO 3232 Schematics but with a different arrangement

This power supply works like a charm and pushed out over 1100 watts. The output voltage was designed for 80-0-80 at 225 volts AC however it will rise to 180 with 235 volts but keeping in mind that it will sag a bit on load thus keeping in the 80 volt region when loaded. I will post a video of the end result when I receive the output caps. The short circuit protection works like a charm and can be adjusted without a lot of hustle, 3 cheers for LUDO for this. The CPU heat sink does it job fine especially when on heavy load and the temperature stays rather cool at say 30-35 degrees C with the fan on. The heat sink was positioned so that it also cools the trafo as the current density of the copper wire is 6 amps per square mm. The efficiency was calculated at 96% when fully loaded. I am posting the full Schematics, PCB, Component layout etc. so one can replicate.

I would like to thank MicrosiM , LUDO and especially Wally for the helpful advice given during this SMPS build


All information is in the PDF file attached.

View attachment 1000W smps final.pdf
 
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Silvio

Active member
Adding a few turns to rise the output of the isolation trafo

IMG_0385.JPG

Checking input and output voltages for comparison

IMG_0387.jpg IMG_0389.JPG
 

Silvio

Active member
1000 watt SMPS based on LUDO 3232 Schematics LOAD TEST

Here is the Load test of the 1000 watt SMPS

[video=youtube;18l-plvqkdU]https://www.youtube.com/watch?v=18l-plvqkdU[/video]
 

villenjak

New member
Hi Silvio,

Very nice project, congrat...
How can I change the number of windings in the secondary for the main voltage +/- 28V 30Amps?
Any help is welcomed :)
 

Silvio

Active member
Hi Villenjak, yes you could change the winding to +/- 28v but you have to give me some details about the core used and the switching frequency and also the mains input voltage. You can also go to switching power supply informations on this site and there is an XL sheet which can calculate the number of turns needed.

Regards,

Silvio
 

Silvio

Active member
Hi Silvio,
I would not change the core (ETD49) and freq. Mains input is 220VAC. Can I change your diagram as attached?

View attachment 6014

Yes you can change the diagram as attached.
1 what core material are you using? (N87, N27, 3c90, etc) Please specify
2 what Power do you need on the main output?
3 What power do you need on the 5v rail.
4 Is the SMPS used for audio?
5 What maximum voltage the amplifier can take? (Please note that the voltage will drop on load as my schematic is not regulated)
6 Are you using my PCB layout with cpu heatsink?
7 do you need aux power for fan and soft start delay?

Please answer all the questions carefully and I will work out for you the number of turns/wire gauge etc for your transformer

Regards

Silvio
 

villenjak

New member
Hi Silvio,
I'll try to answer all questions:
1. N87
2. 900W max.
3. 25W max.
4. No. For UHF linear power amplifier (class AB) 200W SSB (to start, later 400W)
5. 28V max.
6. Yes
7. Yes (maybe 12v)

I hope you can help me

Regards

Villenjak
 
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