Hi ,
How to reduce the transformer hum noise in SMPS which is working in flyback topology?

 

Increase the frequency to above the audio range.

However, if it's an existing design, the transformer will probably have to be replaced.

 

If i have to increase the frequency of switching, it is not possible, because it is fixed frequency switching. And this is not an existing design. what are all the possible reasons for transformer humming?

 

If i have to increase the frequency of switching, it is not possible, because it is fixed frequency switching. And this is not an existing design. what are all the possible reasons for transformer humming?

The transformer humming is mainly caused by the laminations which are not tight well. These laminations vibrate due to the changing magnetic field in the transformer. Humming may be caused by vibrations of the transformer's hoyusinng or windings.

 

A cheap transformer is made with loose parts and no adhesive to keep the parts together.
A good transformer is made properly and is quiet.
You get a cheap transformer if you pay a cheap price.

 

I just can't believe my eyes, why the misinformation you get from these forums, everyone knows transformers hum because they dont know the words!!

Sorry, I just couldn't resist.

 

The only transformer that I have heard make a noise was an overloaded one that made a buzz, not a hum.
I guess I have never heard a cheap transformer.

High power incandescent light bulbs sing the words when they are dimmed. They are smarter than transformers that don't know the words. I also couldn't resist.

 

I just can't believe my eyes, why the misinformation you get from these forums, everyone knows transformers hum because they dont know the words!!

Sorry, I just couldn't resist.

Please don't apologize, that's fantastic.

You know if the hum REALLY bothers you, just enter a deep stage of meditation and don't let it bother you.

Just say ohhhhhhhhhhhhmmmmmm, ha pun fight

 

Reverse the primary.

 

Torch it or blow it to gibs.

 

Reverse the primary.

What is the need for reversing the primary? if we reverse what will happen to flyback action?

 

ok so, as we all know, transformers can make loud robotic noises when they transform. greasing/oiling their joints should help them transform more silently such that they can do it in stealth easier. are your transformers autobots or decepticons?

srsly, epoxy is a great idea.

 

Post diagram in use ?

 

Your guess is as good as mine.