Hello! Yes, by changing the LV impedances I can get the correct results. This is worth noting that the data in the "Model Explorer" in PowerWorld Simulator is in per unit based on the whole system, rather than its real value.
Many thanks. Tian From: bounce-118850794-72551...@list.cornell.edu [mailto:bounce-118850794-72551...@list.cornell.edu] On Behalf Of Carlos E Murillo-Sanchez Sent: Monday, February 23, 2015 22:56 To: MATPOWER discussion forum Subject: Re: Convergence Issue for Distribution Network Power Flow Analysis Hi; You have used the TAP column of the branch table to indicate two transformers with a 55:1 ratio, and then you used the LV impedances, I think, still in PU with a base voltage of 22KV; they are pretty large. The TAP column should be used to specify small variations about 1.0 for true tap-changing transformers. All branch impedances should be specified using a single pu system. I believe that the following is what you are actually trying to run: define_constants; mpc = loadcase('caseSG'); mpc.branch(3:end, BR_R:BR_X) = mpc.branch(3:end, BR_R:BR_X) / 55^2; mpc.branch(3:4, TAP) = 0; runpf(mpc); #ZHANG TIAN# wrote: Dear All, I am using Matpower for a distribution network power flow analysis. The data I used are taken from a real network, and the network is working fine using PowerWorld simulator. Basically, it is a radial network with 14 buses. Bus 1 is the connection point to the main grid, which I modelled it as a slack bus (type 3). However, when converting the model into a Matpower case, I can only get a failure notification "Did NOT converge (0.01 seconds)". Does anyone have any idea about what might be the problem? Or what are the options for me to debug? I attached my case data in this email for your reference. Thank you all very much. Best regards, Tian
