Author Topic: Unidirectional pulse to a transformer  (Read 450 times)

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Offline ZeroResistance

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Unidirectional pulse to a transformer
« on: April 13, 2018, 11:49:13 am »
To understand transformer action I have wound 2 windings on a ferrite flat and was pulsing one of the windings with a unidirectional pulse. And I am getting some some wierd voltage waveforms on the secondary. I just wanted to confirm whether these kind of voltage waveforms are expected on the secondary. I have checking voltage across the second winding in open circuit mode.

Img1 is the currnent pulse measured thru a wire piece in series with the primary winding.
Img2 is the voltage pulse measured across the open circuit secondary winding
 

Online ogden

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Re: Unidirectional pulse to a transformer
« Reply #1 on: April 13, 2018, 11:57:07 am »
To understand transformer action I have wound 2 windings on a ferrite flat and was pulsing one of the windings with a unidirectional pulse. And I am getting some some wierd voltage waveforms on the secondary. I just wanted to confirm whether these kind of voltage waveforms are expected on the secondary. I have checking voltage across the second winding in open circuit mode.

Img1 is the currnent pulse measured thru a wire piece in series with the primary winding.
Img2 is the voltage pulse measured across the open circuit secondary winding

Nothing unusual for open circuit transformer. "Ringing" is normal behavior. Try it in real world application circuit.
« Last Edit: April 13, 2018, 02:49:37 pm by ogden »
 

Offline ZeroResistance

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Re: Unidirectional pulse to a transformer
« Reply #2 on: April 13, 2018, 12:16:00 pm »
Will putting an 100K load across the secondary help?
 

Offline RoGeorge

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Re: Unidirectional pulse to a transformer
« Reply #3 on: April 13, 2018, 12:34:52 pm »
What do you mean by "unidirectional pulse"?

Offline SG-1

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Re: Unidirectional pulse to a transformer
« Reply #4 on: April 13, 2018, 12:51:07 pm »
I think he means only the positive half of the sine wave.

This is similar to using the inductive kick method to determine the polarity of a transformers terminals.  Except a battery is generally used for that, so the input is more of a square wave.
Advice is a dangerous gift, even from the wise to the wise.
 

Online ogden

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Re: Unidirectional pulse to a transformer
« Reply #5 on: April 13, 2018, 02:52:49 pm »
Will putting an 100K load across the secondary help?

Depends on transformer power rating and ratio. What voltage you expect to come out of transformer? What Power you expect to put into transformer? - Knowing output voltage and power, you can calculate resistor value which is needed to dissipate all the power you putting into transformer. Resistor as "test load" is only for testing and your learning. Usually you connect other than resistors, loads.
 


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