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Transformer fed with pulsating DC

Asj

Jan 23, 2012
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If transformer fed with pulsating DC what will happen . As far as DC pulse width is small nothing major will happen . Core will get magnetise and you have demagnetise the core by reversing the polarity
 

Asj

Jan 23, 2012
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If Dc pulse is fed to transformer will there be any voltage transformation to secondary of transformer.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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The most important thing is that (presuming the core isn't saturated) you will get an AC voltage on the secondary and some (possibly significant) heating of the transformer.

You may or may not magnetise the core, it depends on the material it is made up of.
 

davenn

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hi Asj

welcome to the forums

if you notice this is the introductions section of the forum
have a look in the main https://www.electronicspoint.com/ part of the forums and see which section would be the most suitable area to post you question in.
Its more likely to get an answer than when posted in here :)

cheers
Dave
 

Harald Kapp

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Hello Asj,
pulsating DC can be thoought of as DC with overlaid AC. Since the transformer is unable to transfer the DC part of the signal from its primary coil to the secondary, the DC part will only heat the transformer.
You could block the DC by adding a series capacitor to the primary coil. Thus only the AC component of the signal is seen by the transformer. The size of the capacitor depends on factors like frequency of the signal, inductance of the transformer coil, power to be transmitted etc.

Regards,
Harald
 

Asj

Jan 23, 2012
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Transformer

what will happen if i apply Dc pulse to secondary shorted transformer ? What width will be safe ? Wiil transformer go into saturation?
 

Resqueline

Jul 31, 2009
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It depends on the transformer and the resistances and leakage inductances involved.
It'll saturate as fast as the leakage inductance and resistance will allow it to.
We're talking µ-seconds for a ferrite transformer.
Use a fast current sensing circuit to stop.
 

Asj

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If i Apply Dc pulse to secondary shorted transformer how will the current waveform look like ? And since i am removing voltage iimediately so the Energy that is there in Inductor need to be taken care off.How this can be done?
 
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(*steve*)

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Asj, I've combined these three threads because they're all substantially about the same thing.
 

Asj

Jan 23, 2012
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When Dc pulse is applied at rising edge of Pulse the current will start flowing in primary of winding then after certain time secondary of transformer will come in parallel to primary and current will shoot up , but will come down at negative edge of pulse , and current will flow only in primary .
 
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