Given your model, it is not physically possible. The OPF will attempt to use every degree of freedom available to ensure the voltages are kept within range. In your model, however, the OPF has only the VAr injection at the substation that it can use to affect the voltages, which it does by raising the voltage to the upper limit there. However, given your loads, that simply is not enough to keep the downstream bus voltages above 0.95. In other words, you have no way to raise the voltage at your low voltage buses without installing new equipment such as, for example, capacitors or some other source of VArs.
Ray > On Jan 31, 2017, at 1:33 PM, siddique tomal <[email protected]> wrote: > > Dear Ray, > Thanks for reply. Actually I just needed the load flow with facility of > voltage constraints but later on I found that it's not possible in normal > load flow that's why I'm now interested in opf. it provides the facility of > voltage constraints. And my voltage constraints limit is 0.95-1.05 . but now > you're saying to set bus voltage at 0.85 which is lower than lower constraint > value. I would be so much grateful to you if you kindly say if there is any > other way to accomplish my demand. > Thanks > > On Jan 31, 2017 11:34 PM, "Ray Zimmerman" <[email protected] > <mailto:[email protected]>> wrote: > The problem is not feasible due to voltage constraints. Notice that voltages > in the power flow solution go as low as 0.813 p.u., but your case includes > OPF lower bounds on voltages at every bus of 0.95 p.u. Relaxing those voltage > constraints allows the OPF to converge. > > define_constants; > mpc = loadcase('case_radial16'); > mpc.bus(:, VMIN) = 0.85; > r = runopf(mpc); > > > Ray > > > >> On Jan 31, 2017, at 9:55 AM, siddique tomal <[email protected] >> <mailto:[email protected]>> wrote: >> >> Dear Ray, >> Thanks for your reply. I have prepared a 16 bus system. The power flow >> program runs OK with that but when I go for Optimal Power Flow it shows it >> did not convergence. I have attached the file below here. Please would you >> check the file and direct me what to change ? Waiting to hear from you. >> Thanks >> >> On Jan 6, 2017 1:33 AM, "Ray Zimmerman" <[email protected] >> <mailto:[email protected]>> wrote: >> See Section 2.3.1 and Appendix B in the User’s Manual >> <http://www.pserc.cornell.edu/matpower/manual.pdf>. It’s probably easiest to >> start with an existing case file and modify it for your data. Let us know if >> you have a specific question about the case format. >> >> Ray >> >> >> >>> On Jan 2, 2017, at 12:33 PM, siddique tomal <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> Dear all, >>> i need to create a new case file of 16 bus system. i have attached the data >>> table i have now. but my asking is how can i develop a new case file with >>> the following data. its important to mention that the system baseMVA is 100 >>> MVA and base kva of 23 kV. >>> Thanks to all. >>> <16 bus data.png> >> >> <case_radial16.m> >
