What is bad in model? Diode bridge

I would like to make a diode brigde but i have wrong voltage diagram . Whats is wrong in this model?

 Accepted Answer

The structure of the model looks fine to me, although there seem to be other blocks over to the right that could also be affecting results. I'd check a few things:
Remove all the blocks to the right of the voltage sensor. Does the issue go away? It could be all those blocks to the right causing the capacitor to discharge even though you're supplying some current into it from the rectifier piece.
If you replace the capacitor with a resistor, do you get the current profile you expect? It should look like the absolute value of a sine wave. If it doesn't then maybe your diode forward voltage + on resistance are too much for the AC voltage amplitude you are supplying.
Also, a nitpicky thing. Your initial capacitor voltage starts at a negative value and steadies out at zero. This is because the +/- ports are flipped the other way compared to the voltage sensor.
- Sebastian

4 Comments

Wojtek Pichlak
Wojtek Pichlak on 13 Nov 2015
Edited: Wojtek Pichlak on 13 Nov 2015
After remove block on the right side from sensor i have right voltage waveform on first pictures. In this model i make induction motor with inventer. On the right side is include switches. maybe this is reason a wrong working.
When i replace capacitor with resistor voltage waveform is like below
after change +/- ports waveform is rotate. The problem is the initial conditions becouse stars from 3500V and stabilize in -400V.
Wojtek Pichlak
Wojtek Pichlak on 13 Nov 2015
Edited: Wojtek Pichlak on 13 Nov 2015
By the way when i delate block on the right side from phaese splitter and voltage waveworm looks good. I think the problem is Asynchrouse Machine or bad connection this block. probably R or C output.
the problem was location in Asynchronous Machine and exacly Initial stator d-axis magnetic flux linkage had 0.0001 value. Waveform is OK.
Thanks for help
No problem -- looks like you figured it out on your own, though :)

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