Simulink vector space alpha beta transformation

AI Thread Summary
The discussion focuses on creating a three-phase voltage and performing an alpha-beta transformation followed by a Cartesian to Polar transformation to check the output angle. The expected output angle should vary from 0 to 180 degrees and drop to -180 degrees, but the actual results were inconsistent. The issue was identified as being related to the sample rate of the scope, which was initially set too low. By increasing the sample rate from 0.01 to 0.00002, the output angle behaved as expected. The problem was ultimately resolved with this adjustment.
Cdz
Messages
20
Reaction score
1
<< Thread moved to the HH forums from the technical engineering forums, so no HH Template is shown >>[/color]

The model:
model.PNG

reference generation subsystem.png

The goal:
1. Create a three phase voltage
2. Do a alpha-beta transformation
3. Do a Cartesian to Polar transformation
4 Check the output angle
The expected result:
Since the space vector rotates counter-clock wise the angle should from 0 to 180o and drop to -180o(instantly!) and rise again and repeat.
But the actual result is:
result.PNG

As you can see it does not reach 180 or -180 sometimes..I need your help.
 

Attachments

  • result.PNG
    result.PNG
    28.6 KB · Views: 592
  • reference generation subsystem.png
    reference generation subsystem.png
    51.6 KB · Views: 824
Last edited by a moderator:
Physics news on Phys.org
I changed three phase voltage generation part to a Three Phase Sine Generator and the angle output is as I expected.
So the problem lies in three phase voltage generation.
But i can not figure out how that is wrong. Help!
 
Problem solved. The problem is that the scope is running with too low a sample rate. I changed the sample rate from 0.01(default) to 0.00002 and the result is good.
 
Back
Top