Re: infinite bus, 1 branch/1 gen

[Carlos E Murillo-Sanchez]

Russ Patterson wrote: Hi Uriel,   Is there documentation (apologies if I missed it) that explain how the power flow handles input data?  For example,  from the case you just got working for me (attached):   1)      The mpc.bus field “Vm” appears to just be treated as the initial guess for the bus voltage magnitude. 2)      The mpc.bus field “Va” actually fixes the bus angle permanently.   If you change Va to, say 10°, then the load flow result will be:   ================================================================================ |     Bus Data                                                                 | ================================================================================ Bus      Voltage          Generation             Load   #   Mag(pu) Ang(deg)   P (MW)   Q (MVAr)   P (MW)   Q (MVAr) ----- ------- --------  --------  --------  --------  --------     1  1.154   10.000*  -149.60    -39.69       -         -     2  1.174   13.313    149.60     49.10       -         -                         --------  --------  --------  --------                Total:     -0.00      9.41      0.00      0.00   That is a perfectly good result of course.  I am playing around to see what values matter and what don’t – but  I’m wondering if there is a document that explains things like “this is an initial guess” or “this setting fixes this angle” etc.    Best regards, Russ Dear Russ:  Bus #1 is designated as the slack bus (and hence, also for angular reference).  Thus, for this particular bus alone, the angle is assumed known and taken from the respective column in the bus table.  This is a standard power flow assumption. carlos.