Unipolar and bipolar spwm for sine wave inverter.

[israel7732]

what is the difference between Unipolar and bipolar spwm. i have been trying to figure out the differences. please talk on the deficiencies too.

 

[goldsmith]

what is the difference between Unipolar and bipolar spwm. i have been trying to figure out the differences. please talk on the deficiencies too.

Hi
I think you're referring to the two level and three level SPWM signal . right ?
If yes , it depends on what kind of application you're referring to !
For instance , in a sine wave inverter , it will deliver , lower THD ( three level in compare with two level ) . higher efficiency . more linearity . and ... etc .
Or perhaps in a class D amplifier , it will present , lower THD , and better efficiency . and ripple of PSU , won't have any special effect on it's procedure . and also , it will deliver better noise rejection ratio . ( it will increase SNR ) or ... etc .
Best Wishes
Goldsmith

 

[israel7732]

thanks mr gold. please mention the 3 levels.

 

[goldsmith]

thanks mr gold. please mention the 3 levels.

Hi again
Take a look below , please : post #134 . i've sent some pages about this issue . i think you can find what you need in those pages .
https://www.edaboard.com/threads/254847/


Best Wishes
Goldsmith

 

[RONY CHAKRABORTY]

There is a good description of Unipolar, Bipolar and all other method here.
https://www.freescale.com/webapp/sps/site/overview.jsp?code=784_LPBB_HCS08TPM
I have found this helpful