Hi Ray, The methods I have coded are taken from these references:
Current summation method G. X. Luo and A. Semlyen, "Efficient load flow for large weakly meshed networks," IEEE Transactions on Power Systems, vol. 5, no. 4, pp. 1309-1316, Nov 1990. https://doi.org/10.1109/59.99382 Power summation method D. Rajicic, R. Ackovski and R. Taleski, "Voltage correction power flow," IEEE Transactions on Power Delivery, vol. 9, no. 2, pp. 1056-1062, Apr 1994. https://doi.org/10.1109/61.296308 Admittance summation method Dragoslav Rajičić, Rubin Taleski, Two novel methods for radial and weakly meshed network analysis, Electric Power Systems Research, Volume 48, Issue 2, 15 December 1998, Pages 79-87 http://dx.doi.org/10.1016/S0378-7796(98)00067-4 I handle PV buses as described in the second paper, although the first one also treats PV buses and breaked loops in weakly meshed networks. In the second paper the authors have shown better convergence properties of their method. The third one, admittance summation method, is not used very much but I have included it since it is a non-iterative in case when load demand is comprised of constant admittances only. Furthermore it will converge faster in less iterations it the constant admittance is dominant component in the ZIP load model (in my implementation I use the ZIP load model). I think that it will be good if we modify the methods to handle loops in weakly meshed networks. All aforementioned papers have procedures for that. The loops are treated pretty much the same as PV buses so it will require minor changes in the code. I have created pull request. The GitHub is a new thing for me, but I hope we can go through the process smoothly. Regards, Mirko On Thu, Jan 5, 2017 at 8:12 PM, Ray Zimmerman <r...@cornell.edu> wrote: > Hi Mirko, > > Thank you. This looks very nice, and yes, I am interested in seeing > MATPOWER expand it’s applicability for distribution systems. In > fact, I have implemented a prototype Implicit Zbus Gauss power flow > method recently with this in mind. It’s been a while since I’ve > looked at these algorithms, so if you have a pointer to a good > reference on how to handle PV buses, that would be great. > > Regarding your code, I’m still figuring out the ideal workflows, > but I think the best approach is for you to go ahead and create a > pull request where we can discuss and commit any changes before > accepting and merging it into the master branch. I think you’ll > want to create the pull request from a branch in your repo that you > are ok with giving me push access to. > > Thanks, > > Ray > > > >> On Dec 31, 2016, at 10:58 AM, Mirko Todorovski >> <mi...@feit.ukim.edu.mk> wrote: >> >> Dear friends, >> >> I would like to inform you that I have made a "fork" of Matpower on >> github. It can be found at https://github.com/todorovski-m/matpower >> >> I have added three power flow methods which are applicable to >> distribution systems, as well as several distribution test cases >> taken from the literature. The methods are: power summation (a >> version of it known as voltage correction power flow), current >> summation and admittance summation. They can be called if we specify >> the following options: >> mpopt = mpoption('pf.alg','PQSUM') >> mpopt = mpoption('pf.alg','ISUM') >> mpopt = mpoption('pf.alg','YSUM') >> respectively. >> >> The test cases are: case18, case22, case69, case85 and case 141. >> They are all radial, but the methods can solve cases with radial >> networks and arbitrary number of PV generators. They can be easily >> modified to solve weakly meshed networks as well. >> >> For each new file there is a help explaning the purpose of the file >> and a reference for the method or case data. There is a file >> test_radial.m where I compare the results with those obtained by >> Newton method. >> >> I wonder if there is an interest to develop Matpower in this >> direction. Please give me your comment and opinions on the matter. >> >> Best wishes for the new year, >> Mirko Todorovski >
