Hi all, I am also having problems to convert the R,X,B values from ohms and (myFarat) to pu. I try to use UCTE Data as input files. These values are in ohms and I need to convert them to pu.
I chose a MVAbase of 100MVa and used x(pu) = X*baseMVA/(Ur^2). Same for R. It seems to work for the real part but my reactive power is too much off. In big grid models I get incredibly high reactive power flows. What did I do wrong here? Von: [email protected] [mailto:[email protected]] Im Auftrag von Petre Razusi Gesendet: Montag, 13. Mai 2013 09:45 An: MATPOWER discussion forum Betreff: branch modeling Dear all, I have some things I don't quite understand regarding the modeling of branches and the pu system. If I'm not wrong, to transform the R,X and B parameters to pu one needs a base impedance. Since the model used for the branch is a complex one, dealing with both transformers and lines, I presume that this impedance is calculated using the "to" bus voltage. Am I right? And if so, could you tell me what is the formula used to compute the base impedance? Thanks, Petre
