Re:Re: Power flow calculation when changing the network topology
Dear Ahmad,
Thanks for your suggestions!
I've tried several power flow algorithms ('NR', 'GS', 'YSUM', etc.)
referring to the manual, but the calculation all fails.
Considering your last advice, today I'm searching for explanations of power
flow calculation failure. And I get that inappropriate network parameter
setting can also lead to convergence failure for connected radiality networks.
I reduce the default node loads by half and the power flow calculation
succeeds. It turns out that the parameter setting needs to be further
considered for reconfigured networks.
(Reference:
http://help.easypower.com/ezp/9.6/content/07_power_flow_analysis/Troubleshooting_Power_Flows_that_Fail_to_Solve.htm)
Best regards,
Yan
发件人：Ahmad Sadiq Abubakar
发送日期：2022-05-01 12:01:10
收件人：MATPOWER discussion forum
主题：Re: Power flow calculation when changing the network topology
Dear Yan,
Yes to your first question. The STATUS determine the connectivity or otherwise
of a branch.
On the second question, there are algorithm for running Distribution power flow
different from runpf.
Kindly refer to the manual for about three different distribution power flow
algorithm and how they are invoked.
Lastly, not all reconfigured topology may necessarily converged even with
distribution power flow algorithm. So, be sure while implementing the
reconfiguration, you don't create Island..
Hope this helps. Regards.
On Sat, Apr 30, 2022, 5:30 PM Ziheng Yan wrote:
Dears,
I‘m trying to calculate power flow in distribution systems considering
network reconfiguration. From the data format description, I noticed that the
11th column of mpc.branch named BR_STATUS represents "initial branch status".
But I'm not sure whether that attribute means the on/off status of branches and
thus determines the network topology. Take 'case33bw' as an example, when I was
trying to change the 11th column of mpc.branch (network connectivity and
radiality is guaranteed) and execute runpf, the power flow calculation fails to
converge in some network topology (success=0 and it reaches max iterations). I
have tried several power flow algorithms as well as increase the max number of
iterations, but all fails. So the question I'm gonna ask is:
1) While doing power flow calculation, does BR_STATUS determine the network
topology?
2) Any suggestions for cases where power flow cannot converge?
Thank you in advance, early reply is appreciated.
Regards,
Yan
Re: Power flow calculation when changing the network topology
Dear Yan, Yes to your first question. The STATUS determine the connectivity or otherwise of a branch. On the second question, there are algorithm for running Distribution power flow different from runpf. Kindly refer to the manual for about three different distribution power flow algorithm and how they are invoked. Lastly, not all reconfigured topology may necessarily converged even with distribution power flow algorithm. So, be sure while implementing the reconfiguration, you don't create Island.. Hope this helps. Regards. On Sat, Apr 30, 2022, 5:30 PM Ziheng Yan wrote: > Dears, > >I‘m trying to calculate power flow in distribution systems considering > network reconfiguration. From the data format description, I noticed that > the 11th column of mpc.branch named BR_STATUS represents "initial branch > status". But I'm not sure whether that attribute means the on/off status of > branches and thus determines the network topology. Take 'case33bw' as an > example, when I was trying to change the 11th column of mpc.branch (network > connectivity and radiality is guaranteed) and execute runpf, the power flow > calculation fails to converge in some network topology (success=0 and it > reaches max iterations). I have tried several power flow algorithms as well > as increase the max number of iterations, but all fails. So the question > I'm gonna ask is: > >1) While doing power flow calculation, does BR_STATUS determine the > network topology? >2) Any suggestions for cases where power flow cannot converge? > >Thank you in advance, early reply is appreciated. > > > Regards, > Yan > > > >
Power flow calculation when changing the network topology
Dears, I‘m trying to calculate power flow in distribution systems considering network reconfiguration. From the data format description, I noticed that the 11th column of mpc.branch named BR_STATUS represents "initial branch status". But I'm not sure whether that attribute means the on/off status of branches and thus determines the network topology. Take 'case33bw' as an example, when I was trying to change the 11th column of mpc.branch (network connectivity and radiality is guaranteed) and execute runpf, the power flow calculation fails to converge in some network topology (success=0 and it reaches max iterations). I have tried several power flow algorithms as well as increase the max number of iterations, but all fails. So the question I'm gonna ask is: 1) While doing power flow calculation, does BR_STATUS determine the network topology? 2) Any suggestions for cases where power flow cannot converge? Thank you in advance, early reply is appreciated. Regards, Yan
