diyAudio

diyAudio (http://www.diyaudio.com/forums/)
-   Power Supplies (http://www.diyaudio.com/forums/power-supplies/)
-   -   Leco smps some ugly tests... (http://www.diyaudio.com/forums/power-supplies/204158-leco-smps-some-ugly-tests.html)

DjLeco 10th January 2012 12:14 AM

Leco smps some ugly tests...
 
Leco SMPS on 12 ohms loading , 140,5 volts DC output on idle, 139,5volts DC on 12 ohms load.

50 Ampres/100milivolts shunt seried , shows 22,6 mV on it ,so curent on load is 11,25 Amperes.

Power is 11,25A x 139,5V = 1509.5 watts

Leco SMPS 12 ohms loading.MOV - YouTube



Leco SMPS on 4 ohms loading , 140,5 volts DC output on idle, 126,4 volts DC on 4 ohms load.

50 Ampres/100milivolts shunt seried , shows 54,2 mV on it ,so curent on load is 26 Amperes.

Power is 26A x 126,4V = 3272 watts




Leco SMPS on 2,66 ohms loading , 127 volts DC output on idle, 115,5volts DC on 2,66 ohms load.

50 Ampres/100milivolts shunt seried , shows 76,4 mV on it ,so curent on load is 36 Amperes.

Power is 36A x 115,5V = 4135 watts


Leco SMPS a and 2,66 ohms loading.MOV - YouTube

dexter2003 11th January 2012 09:04 PM

Quote:

Originally Posted by DjLeco (Post 2854450)
Leco SMPS on 12 ohms loading , 140,5 volts DC output on idle, 139,5volts DC on 12 ohms load.

50 Ampres/100milivolts shunt seried , shows 22,6 mV on it ,so curent on load is 11,25 Amperes.

Power is 11,25A x 139,5V = 1509.5 watts

Leco SMPS 12 ohms loading.MOV - YouTube



Leco SMPS on 4 ohms loading , 140,5 volts DC output on idle, 126,4 volts DC on 4 ohms load.


50 Ampres/100milivolts shunt seried , shows 54,2 mV on it ,so curent on load is 26 Amperes.

Power is 26A x 126,4V = 3272 watts




Leco SMPS on 2,66 ohms loading , 127 volts DC output on idle, 115,5volts DC on 2,66 ohms load.

50 Ampres/100milivolts shunt seried , shows 76,4 mV on it ,so curent on load is 36 Amperes.

Power is 36A x 115,5V = 4135 watts


Leco SMPS a and 2,66 ohms loading.MOV - YouTube




Nice work !

It's the half bridge with Igbt isn't it ?
Make another test with a 3kw load and keep it for 30 minutes :) .
I suppose the transformer is wound with litz wire , 4 kw peak for audio is goood .

I like the smps , but i don't like the igbt , if you used them , because of their hi VCE , let's suppose 2V at 30 A , 60W that's only the conduction losses + some small switching losses .
If i were you , I would try some robust mosfet with 0.03 ohm Rds, that will give you 0.8V drop , a huge improvement , the only drawback is the huge gate charge (in the range of 30nF).

Keep the good work!

DjLeco 12th January 2012 12:03 AM

Man, it was just a simple test; final one, I think will be full bridge for 1/2 curent on primary, and less Ic on output switching devices.
In that test, I was limmited from small heatsink of rectifier diodes, and resonant capacitor curent cappability...

I have very low loss on switching devices, gratefully almost perfect drive of it, very low rise and fall times.

Look here:

Proper IGBT driving, on mine SMPS (100Khz half bridhe resonant soft switching mode)


Observe ULTRAFAST switching, very low rise and fall timmings.

View image: DSCN5197

Tomorrob (today better said) I will try full bridge tipology, at 62,5 , 100 , and 125 Khz.

Mine IGBT;s are WARP ones (150Khz hard switching, 300 Khz soft switching).

Not interested to use mosfets, due internal body diode, also I don;t want to complicate output topology with schottky and antiparralel diodes too.

All modern SMPS, uses IGBT, or combination of mixed IGBT with mosfet too, also not interested...

Simple one, is most time, the efficient one!

If I lose under 100 Watts per total SMPS at 4000W total load, randament is HUGE, also, musical power is not more than 1/2 from a pure sin wave, or dummy load as I tested.

Next time, I will use, maybe bigger power resistors for dummy load, for longer time testing, If I keept that test, mine 4 ohms resistor will melt itself...

dexter2003 12th January 2012 04:16 AM

Quote:

Originally Posted by DjLeco (Post 2857600)
Man, it was just a simple test; final one, I think will be full bridge for 1/2 curent on primary, and less Ic on output switching devices.
In that test, I was limmited from small heatsink of rectifier diodes, and resonant capacitor curent cappability...

I have very low loss on switching devices, gratefully almost perfect drive of it, very low rise and fall times.

Look here:

Proper IGBT driving, on mine SMPS (100Khz half bridhe resonant soft switching mode)


Observe ULTRAFAST switching, very low rise and fall timmings.

View image: DSCN5197

Tomorrob (today better said) I will try full bridge tipology, at 62,5 , 100 , and 125 Khz.

Mine IGBT;s are WARP ones (150Khz hard switching, 300 Khz soft switching).

Not interested to use mosfets, due internal body diode, also I don;t want to complicate output topology with schottky and antiparralel diodes too.

All modern SMPS, uses IGBT, or combination of mixed IGBT with mosfet too, also not interested...

Simple one, is most time, the efficient one!

If I lose under 100 Watts per total SMPS at 4000W total load, randament is HUGE, also, musical power is not more than 1/2 from a pure sin wave, or dummy load as I tested.

Next time, I will use, maybe bigger power resistors for dummy load, for longer time testing, If I keept that test, mine 4 ohms resistor will melt itself...

That signal is before the gate rezistor? it looks too dam fast . At my amps rise time is something in the range of 180ns if i remember correctly ,today i will test it ,and i'm using 9A gate drivers ,gate charge something like 18nF.....

Kv3audio 12th January 2012 04:37 PM

Quote:

Originally Posted by dexter2003 (Post 2857369)
Nice work !

It's the half bridge with Igbt isn't it ?
Make another test with a 3kw load and keep it for 30 minutes :) .
I suppose the transformer is wound with litz wire , 4 kw peak for audio is goood .

I like the smps , but i don't like the igbt , if you used them , because of their hi VCE , let's suppose 2V at 30 A , 60W that's only the conduction losses + some small switching losses .
If i were you , I would try some robust mosfet with 0.03 ohm Rds, that will give you 0.8V drop , a huge improvement , the only drawback is the huge gate charge (in the range of 30nF).

Keep the good work!


I am sure that Lecos wont spend time making that simple test for his robust SMPS.

Waiting to see yours holding 2.6KW for 13 minutes, not 30 :p

DjLeco 12th January 2012 09:44 PM

Kv3audio, I smell a little jealousy?

As you saw, that resistor is NOT capable for taking that amount of power, much than one minute without destroying.

When I have time, I will make another test on 4 Kw dummy load, so, after 15 minutes of load, what you will tell?

You stick the nail in the neck?

Kv3audio 12th January 2012 11:21 PM

nope

Your SMPS will heat like hell for 15 minutes loaded, good luck

also I dont care for both results

DjLeco 13th January 2012 10:09 AM

So, if you don't care about anyone of results, why have you post here?

Post hunting or?

Nothing personally with you , or anyone else, but your post above, looks a little...

pergo 13th January 2012 10:22 AM

best congrats for you!

Do you use this SMPS for your amps?
The main voltage is 220V or 110V?

palstanturhin 13th January 2012 11:31 AM

Good job!
What is the efficiency of it?


All times are GMT. The time now is 06:06 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio


Content Relevant URLs by vBSEO 3.3.2