# PSpice Simulation - Bridge Rectifier

1. Aug 25, 2007

### lim1991

Hi, i'm having a problem while running a simulation of a Bridge Rectifier on PSpice.

This is my circuit schematic:

Vs is at 15sin(100*pi*t).

And this is the input and output waveforms plotted by PSpice.

http://img338.imageshack.us/img338/6281/untitledpb6.jpg [Broken]

I'm aware that my input wave should have a symmetrical peak-to-peak value but i can't get it on PSpice. I have asked around and was assured that my schematic and output wave is ok, but there's no answer to why my input wave is like that .

Using PSpice Student Version 9.1.

Last edited by a moderator: May 3, 2017
2. Aug 25, 2007

### AlephZero

It looks like a plot of Vs measured relative to your earth point.

The + and - terminals of your voltage source are both floating relative to earth. Presumably there is a way to plot the voltage difference between two points, if that's what you want to see. (I don't know PSPICE so I can't help on how to do that).

3. Aug 25, 2007

### lim1991

Hi, thhank you for the reply.

Yes, i know it i s measured relatively to the earth point. But if i ground the circuit somewhere else, i will get the wanted Vs wave, but then the output wave will be that of a half-wave rectifier.

I am required to plot the sinewaves for Vs and Vo ( voltage across resistor ).

4. Aug 26, 2007

### AlephZero

OK, I'll try saying the same thing again in different words.

The "input wave" is the voltage difference between the + and - terminals of your voltage source. It's got nothing to do with the voltage between one of those terminals and ground.

You need to find out how to plot the voltage difference between any two node points in a PSPICE simulation. People do this all the time testing real circuits with real voltmeters and oscilloscopes, so there must be an easy way to do it in PSPICE otherwise the program would be fairly useless for doing real work!

But I don't use PSPICE so I can't tell you how to do it - sorry. Try looking at the tutorial or demo problems, or if all else fails read the manual.

5. Apr 20, 2010

### EE_guy

Hello,

I believe the window where you can see/add traces or graphs of the desired output gives you, as one of the options in the little panes, the ability to graph such a difference between nodes. It is called voltage differential. It should also appear in the schematic window before you run the simulation. It allows you to place two voltage markers one at each of the nodes of interest. After running the simulation, you should be able to go into the add trace menu and see the differential voltage noted as Vout(1:2) or something like that.