Check my simple PPL structure with a pure sine wave

[aabbddlah]

i was asked to design a simple PPL structure with a pure sine wave
, run the simulation and get the results that prove that PLL works.


i v done that so
could u guys have a look at the attachments

and tell me if i v got something wrong in the simulink file
or the outputs
many thanks

 

[tbui]

Simple PLL

Fref = Fout ?
I don't think that makes sense.

 

[aabbddlah]

Re: Simple PLL

i am new to this topic
could u plz tell me what to alter in the circuit then

many thanks

 

[LvW]

Re: Simple PLL

i was asked to design a simple PPL structure with a pure sine wave
, run the simulation and get the results that prove that PLL works.

Question: Do you know something about the function (task) of a PLL ?
Otherwise, you cannot see if it "works" or not.
Question: What kind of loop filter?
(Is "Butter" an indication for a Butterworth filter of 2nd order? This will not work!)

 

[saro_k_82]

Re: Simple PLL

(Is "Butter" an indication for a Butterworth filter of 2nd order? This will not work!)

Why LvW?

 

[LvW]

Re: Simple PLL

Since the VCO creates one pol, your PLL would be of 3rd order, which leads to instability of the closed loop system. You should use only a 1st order lowpass with an additional zero or a PI filter.

 

[anastasia]

Re: Simple PLL

i was asked to design a simple PPL structure with a pure sine wave
, run the simulation and get the results that prove that PLL works.


i v done that so
could u guys have a look at the attachments

and tell me if i v got something wrong in the simulink file
or the outputs
many thanks