1kW smps project (based on MicrosiM design)

[badboy_6120]

View attachment 5616View attachment 5617View attachment 5618I have 2x680uF in series at primary (eqivalent 340uF).
Trafo ratio is n=3. The secondary side capactance is 4x1000uF (2000uF per rail).
I am getting ripple at secodary side exacly 2.8Vp-p.

After adding another 2 caps 1000uF/200V at each rail (i have 840uF equivalent capacity at primary side), I am getting around 2,45Vp-p ripple at secondary (measured from V- rail to V+ rail).

badboy --> that is why I am so surprised that you have only around 100mV ripple at secondary (screanshoot no6 50mV/div).

I must do some more investigation at my board.

for screenshots number 1 to 3 I set oscilloscope in 50X mode (10X switch on the probe and 5X on the oscilloscope) and I forgot to set it back for screenshot no6 (50mV/div)
So with 540W load I have 4V p-p ripple not 100mv

8x0.2x5x10x50x10^-3 = 4V

 

[badboy_6120]

Here's the measurement without 50X attenuation
*** Chanel 2 ***
*** 2V/div ***




The ripple is actually less than 3V p-p in about 550W load

 

[borysgo2]

badboy
Thanks a lot, that is making a lot of sense to me now.
The additional capacitance at primary helps a lot.

Regards Peter

 

[badboy_6120]

badboy
Thanks a lot, that is making a lot of sense to me now.
The additional capacitance at primary helps a lot.

Regards Peter

happy to help

by the way 3V p-p is with 5A output current, as I said earlier I changed the main transformer to a lower voltage for some test (56-0-56)

good luck

 

[stewin]

It's possible with a minor rework. However I don't recommend using it to power up a PWM controller (use what you have on your schematic instead).

thanks sir i used the circuit on schema .it worked well , i have used mje340 instead of tip50 all is cool and well. but i still need to coil the main former properly . will post results

 

[badboy_6120]

Hi guys

I connect the smps to a 200W amplifier (4 0hms) and I have some lousy noise on amplifier output without any input signal


I even short cut the amplifier's input but the same noise with a little attenuation exist on the output

with traditional power supply (50Hz transformer and 22000uf on each rail) I have a nice and clean output without any input signal
here's the schematic of my current amplifier

 

[Jagd.Panther]

What channel/probe did you use? is that +-400mV on amp out?

 

[badboy_6120]

What channel/probe did you use?

Hi "Jagd.Panther"
It's on channel two
Volts/Div = 50mv
Time/Div = 5 us
probe attenuation is on 1X

is that +-400mV on amp out?

If you're talking about the peak to peak of sparks, yeh that's right


I added some snubbers to smps and now the sparks on amplifier's output is less than 80mV peak to peak

The snubbers are :
1nf/10 ohms 2W on each IGBT's collector-Emitter
2.2nf / 10 ohms 0.25W on each main transformer secondaries

 

[vikram singh]

could anyone help for starting the basic of microcontroller programming
i have pic programming kit

 

[tsalz]

Anyone have a complete parts list for the 2.1 version? Some parts such as R4,R5,C21,C22 are not specified. I read the entire thread and never found anyone mentioning this or a complete BOM.

 

[protech1104]

this smps. will explode. after 5 min max.

 

[ikemhla]

1kW smps project(Based on MicrosiM Design)

A warm Hi to you all.

I am new to this forum.

I am interested in building this smps. Can someone help me and guide me through he whole process.

I find this project very fascinating. I need +75 and -75 volts for my amp.

Thank you all in advance for your help.


Regards

Ike

 

[protech1104]

Yes i can help you . Schematic part and evry think but in confideciel

 

[ikemhla]

protech1104

Thank you for the offer for assistence.

I shall PM you and we can take the matter further.

Regards

Ike

 

[protech1104]

with pleasure

 

[CkmTronik]

help...sir please shared flyback transformer turn ratio calculation...

sory bad my english

 

[Weller]

help...sir please shared flyback transformer turn ratio calculation...

sory bad my english

This topic is not about flayback trafos since with pushpull technic we don´t store energy in the core (gap actually).

 

[ludo3232]

ALL files

Hi all,

All files are here :


View attachment SMPS.zip

 

[stewin]

hi all i found this protect schema on the web by schutzschaltung . i tried it and it works well with my smps .
but i wanted to increase the current limit to about 8 amperes or even 15 amperes . where can i adjust??

 

[stewin]

Hi all,

All files are here :


View attachment 5939

thanks ludo for the files they are great