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#1 Jan 15, 2018
thienbaotan
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Unexpected waveform when measuring power of an AC source

Here I construct a circuit like this: https://drive.google.com/file/d/1vQpMv4zMCwWEVPU-xe5RJrONDJXWRfvb/view?u...

My simulation configuration:

+ Step size: 1us

+ Simulation time: 20ms

But I don't know why the waveform is so weird: https://drive.google.com/open?id=1GRuMI41FfU7uT9Ai0Wflo816txwnQ8qc

Can anyone help me this? Thank you very much in advance.

Mon, 2018-01-15 03:46
RobertoGb
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Hi,

I would like to know which version and hotfix you use. 

On the other hand, I would like to simulate the same circuit at my end and chech if this issue is reproducible. Could you tell me please the properties of the transformers you are using or send me directly the project (PSpice@flowcad.de)? 

Regards

Mon, 2018-01-15 04:02 (Reply to #2)
thienbaotan
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I use version Orcad 17.2, Lite version. The transformer is XFRM_NONLINEAR. Thank you so much. 

I found out that if I let the value of R1 <1p, the simulation looks like what i sent you. Meanwhile, if the value is 1p, the result is a curve line but still not a periodic waveform (pretty weird waveform)

https://drive.google.com/open?id=1WbqJLAeF2vh0CqzZCAkixUW8zD_leb6M

Mon, 2018-01-15 04:12
RobertoGb
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Hi,

I do not know what the reason is. I simulated at my end and it does not look like your curve. I do not think it is related with the version you are using. Could you send me your files please? 

Mon, 2018-01-15 04:18 (Reply to #4)
thienbaotan
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Mon, 2018-01-15 07:34
RobertoGb
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Hi,

So now I am able to get the same issue than you. You did not tell in your previous messages, that you also configured the transformer with different values for the transformers turns in relation to the default ones. 

Anyway, now I am getting the same results than you. However, I do not understand, why they change just because of the value of the resistor. Let me investigate a little bit more. 

Regards

Mon, 2018-01-15 10:15 (Reply to #6)
thienbaotan
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OMG, i'm so sorry, i forgot that :( 

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