Hello,

I'm reading the source code (newtonpf.m) and noticed the following lines used 
to indexing and updating the four "quadrants" of the J matrix according to 
which variables are updated depending on whether it's a PV, PQ or Ref bus:
[cid:29941cfc-bf59-448b-bfcb-d1f412caaa32]

My question is, doesn't this assume the ordering of PV-PQ-Ref buses in any V, I 
or S vectors (that are N_BUS x 1 in size)? That is, say there are 9 buses, 
where 1 is Ref,  4,6,7 are PV , and 2,3,5,8,9 are PQ, then the buses would be 
ordered like so before this function was called:

         4,6,7   2,3,5,8,9      1         (indices are sorted by bus type)
          (PV)       (PQ)       (Ref)

And according to the source code it would've been
         1,2,3   4,5,6,7,8,    9
          (PV)       (PQ)       (Ref)

But I didn't notice where this assumption was checked to be valid...

I was thinking it should instead be:

     Idx_PQ = [(internal/consecutive) indices of PQ buses, sorted]
     Idx_PV = [... PV ...]
     Idx_Ref = [... Ref ...]  (of course there would only be 1 element)

and index as J11 = real(dSbus_dVa[all except Idx_Ref, all except Idx_Ref]), and 
so on for J12, J21, and J22. But if the source code was truly incorrect in this 
regard, surely it must have been pointed out before, so I'm thinking I made a 
mistake somewhere.

Could you please point out where I'm wrong? Your time and help are much 
appreciated.

Regards,
Liangjie Chen

Reply via email to