Single-Phase TRANSFORMER Simulation


  #1  
Old 11-21-05, 02:47 AM
Zedone
Visiting Guest
Posts: n/a
Arrow Single-Phase TRANSFORMER Simulation

Hi,

I want to simulate a single-phase transformer circuit with
-open circuit
-short circuit
-inductive
-capacitive
-resistive load tests.

What do you suggest me as a circuit simulation program and what steps I should follow in that type of circuit?

Thanks in Advance
 
  #2  
Old 11-21-05, 07:49 AM
5
Member
Join Date: Nov 2004
Location: CA
Posts: 1,913
Upvotes: 0
Received 0 Upvotes on 0 Posts
Any electrical or electronic function can be expressed as an "equivalent circuit" of resistance, inductance, and capacitance.

I am 30 years removed from advanced electronic theory and design training ( Navy C-7 school) and 18 years out of that industry alltogether, so CRS prevents further elucidation. So I just suggest you refer to your basic electrical and electronic texts.

As far as a computer simulation, try Google. The last computer I worked on in the Navy had an 8K hard drive. YES "K" !
 
  #3  
Old 11-21-05, 04:54 PM
Zedone
Visiting Guest
Posts: n/a
Thanks for the help Mr 594tough.

i now installed multisim 8. i try to make the entire circuit. but something is wrong that circuit doesnt work. i think that where i make wrong.

i attach the circuit schematic below.
http://img502.imageshack.us/my.php?i...sformer1wv.jpg

I need to make the open circuit of the single phase transformer circuit... From U3 voltmeter side, i want to measure the open circuit voltage.

Vs (function generator)=90V
F=100 Hz
----open circuit test----
1- With the variable ratio auto-transformer set to sero switch on
2- Raise the voltage in steps of 20% to the rated voltage of 120V
3- Measure and read the results.

pls help.
Thanks
 
  #4  
Old 11-21-05, 08:12 PM
G
Member
Join Date: Oct 2004
Location: USA
Posts: 676
Upvotes: 0
Received 0 Upvotes on 0 Posts
I have version 5 its less temperamental.

R1 you have 100meg why ? That's to large, you may have it connected wrong. looks like a control.
Set all meters to AC. you have U3 set to DC.


I would use a power transformer.
some times you need to add a ground to the secondary side of the xformer. the center tap looks like the best spot.

You have an unconnected center tap on the primary side.
Sometimes EWB does not like un-connected lines.
 
  #5  
Old 11-22-05, 05:06 AM
W
Member
Join Date: Jan 2004
Location: Oregon
Posts: 1,104
Upvotes: 0
Received 0 Upvotes on 0 Posts
In your diagram, you do not have a variable ratio auto-transformer. You have a fixed ratio transformer.

You have a potentiometer (variable resistance), however your circuit is connected to both resistive element terminals, not to the 'wiper'. If you want to use the component as a variable resistance, you have to use one of the resistive element terminals and the wiper.

You have no significant load on the secondary side. As soon as sufficient current flows on the primary side to provide magnetization, you will have full voltage on the secondary side. The current required will depend upon how 'perfect' the transformer is.

-Jon
 
  #6  
Old 11-22-05, 05:26 AM
Zedone
Visiting Guest
Posts: n/a
there are similar shapes when i look at the transformer section in the multisim8. so i dont know which one is the single-phase transformer. i gave the schematic to give a general opinion.

thank you very much for your helps. i need a clear understanding even if i had a bad english.

i installed circuitmaker also. but there is no such like a transformer. there are different shapes.
 
  #7  
Old 11-22-05, 06:13 AM
W
Member
Join Date: Jan 2004
Location: Oregon
Posts: 1,104
Upvotes: 0
Received 0 Upvotes on 0 Posts
In your diagram, T1 _is_ a single phase transformer.

Specifically it is a single phase, center tapped, isolation transformer. This means that there is a single primary coil and a single secondary coil, that each coil has an electrical connection in the center, and that the two coils are not electrically connected.

You said that you wanted to model a single phase variable autotransformer. An 'auto'transformer has a _single_ coil, with both primary and secondary taps on the _same_ coil. A _variable_ autotransformer means that you have a single coil with a couple of primary taps for the input, an a _moving_ secondary tap for the variable output. There is a nice diagram on this page:
http://www.nmr.mgh.harvard.edu/~reese/VariacPage/

-Jon
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: