modeling PWM stage- how to calculate the phase shift?

[mengcy]

modeling PWM stage

Hi,I am modeling a PWM stage.
it's usually modelled as a linear gain stage whose gain is VDD/VTRI. VDD is the power supply voltage,VTRI is the swing of the carrier.

My question is: this linearization model doesn't consider the phase factor. sometimes there is a large delay in the real circuit, it may cause a phase shift. how to calculate the phase shift?

Thanks in advance.

 

[sunbeam]

modeling PWM stage

It depends on your siulation,tran or AC?

delta therta = 2*pi*delay/sampling period.

 

[mengcy]

modeling PWM stage

That is a possible answer.
is there any theoretical support?