The bus 1 has constant voltage and it is considered as an infinite bus. The negative active power means that PVs send power to the grid.
Στις 24 Νοε 2016 13:33, ο χρήστης "Saranya A" <[email protected]> έγραψε: > I dont see in the case file where you have connected the Bus 1 to the grid. > Can you clarify on this? > > On Thu, Nov 24, 2016 at 1:31 PM, Alexandros Gesios < > [email protected]> wrote: > >> Bus 1 represents the grid connection which has negative active power >> because the active power from PV is larger that the load active power. >> >> Στις 24 Νοε 2016 07:38, ο χρήστης "Saranya A" <[email protected]> έγραψε: >> >>> I ran the "casePV3" and observed that bus 1 which is slack bus has Pg as >>> -3MW. Can a bus which has photovoltaic unit as generator observe real >>> power? I am not pretty aware of the power electronics of it. I think if you >>> can reason that out you may get some direction. >>> >>> Regards, >>> Saranya A >>> >>> On Thu, Nov 24, 2016 at 4:08 AM, Alexandros Gesios < >>> [email protected]> wrote: >>> >>>> Ι made some changes in the matrices and OPF completes but I do not >>>> think that it allocates the reactive power among the PVs in an optimal way >>>> regarding the losses. >>>> The last three PVs absorb Qm reactive power while the other operate in >>>> a unity power factor. >>>> I attach the case in order to be more specific. Also the network is >>>> radial. >>>> >>>> >>>> 2016-11-23 20:46 GMT+02:00 Alexandros Gesios < >>>> [email protected]>: >>>> >>>>> Dr. Zimmerman >>>>> >>>>> >>>>> I applied the change you have mentioned and the result is the following: >>>>> >>>>> >>>>> MATPOWER Version 6.0b1, 01-Jun-2016 -- AC Optimal Power Flow >>>>> MATLAB Interior Point Solver -- MIPS, Version 1.2.1, 01-Jun-2016 >>>>> (using built-in linear solver) >>>>> Numerically Failed >>>>> >>>>> Did not converge in 9 iterations. >>>>> >>>>> >>>>> Did NOT converge (0.11 seconds) <<<<< >>>>> >>>>> >>>>> >>>>> >>>>> 2016-11-23 19:54 GMT+02:00 Ray Zimmerman <[email protected]>: >>>>> >>>>>> I think you want to change the first column of your gencost entries >>>>>> to 2 (polynomial) instead of 1 (piecewise linear). Hopefully, that fixes >>>>>> your problem and it will solve. >>>>>> >>>>>> Ray >>>>>> >>>>>> > On Nov 23, 2016, at 10:30 AM, Alexandros Gesios < >>>>>> [email protected]> wrote: >>>>>> > >>>>>> > Hello to everyone >>>>>> > >>>>>> > I am new to MATPOWER and I am trying to operate an OPF analysis in >>>>>> a MV grid constisted of two feeders. >>>>>> > The first feeder has 10 inductive loads and the second feeder has >>>>>> 10 photovoltaic units and their are connected to the grid by the slack >>>>>> bus. >>>>>> > What I want to achieve is loss minimization by allocating the >>>>>> reactive power among the photovoltaic units in a optimal way. The nominal >>>>>> active power of the PV units is 10.6 MW and the load is 6 MW so the extra >>>>>> active power is being absorbed by the HV/MV Grid. >>>>>> > Also I want the slack bus to operate at constant 1.05 pu voltage so >>>>>> in the mpc.bus slack bus has voltage limits Vmax=Vmin=1.05. >>>>>> > Also I want the PV units to operate in nominal power so in mpc.gen >>>>>> their active power limits are Pmax=Pmin=Pnom. >>>>>> > >>>>>> > Finally the mpc.gencost matrix constists of 11 rows and every row >>>>>> has these elements 1 0 0 2 2 4; because I read >>>>>> in the archive that in order to achieve loss minimization you need the >>>>>> same >>>>>> linear costs in the gencost matrix. >>>>>> > >>>>>> > When I run runopf(mycase) I take the following errors >>>>>> > >>>>>> > Index exceeds matrix dimensions. >>>>>> > >>>>>> > Error in opf_setup (line 84) >>>>>> > x1 = mpc.gencost(pwl1, COST+2); >>>>>> > >>>>>> > Error in opf (line 198) >>>>>> > om = opf_setup(mpc, mpopt); >>>>>> > >>>>>> > Error in runopf (line 75) >>>>>> > [r, success] = opf(casedata, mpopt); >>>>>> > >>>>>> > Also, I would like to ask whether my problem can be formulated in >>>>>> MATPOWER. >>>>>> > >>>>>> > >>>>>> > Thank you in advance >>>>>> > >>>>>> > >>>>>> > Alexandros Gesios >>>>>> >>>>>> >>>>>> >>>>>> >>>>> >>>> >>> >
