Gelli, I'm not sure whether you have turned on the option pf.enforce_q_lims (help mpoption) to enforce Q limits for the power flow solver.
Q limits should be applied once the power flow is at, or fairly close, to an "actual" solution. If the limits are imposed during the Newton (or gausspf) iterations [the initial iterates may not be close to the actual solution] then there may be potential solver stability issue. MATPOWER could possibly incorporate some logic for handling Q limits in the routines (Newton, Gauss-Siedel, Fast-Decoupled) called by runpf() but then it is a headache for code maintenance as now any change to the logic has to be replicated in all the routines! Shri From: Gelli Ravikumar <[email protected]<mailto:[email protected]>> Reply-To: MATPOWER discussion forum <[email protected]<mailto:[email protected]>> Date: Fri, 22 Aug 2014 14:31:29 +0530 To: MATPOWER discussion forum <[email protected]<mailto:[email protected]>> Subject: Re: Type switching of PV buses to PQ buses with reference to Q limits in Load flow The concepts are well known for handling the switching mechanism of PV to PQ while executing load flow programs. But, my question is that: This was not tackled in the gausspf.m and newtonpf.m of the MatPower package, just have a glimpse over those load flow programs. However, these functions are used to call from the runpf.m. If you observed the runpf.m prgram, after the power-flow solution obtained from any of the "PF_ALG"s, the q limits check have been done to just intimate the users as a message like the limits are violated. -- with Regards ---------------------------------------------------- Gelli Ravikumar Research Scholar (Ph.D), Field Computations Lab, Dept. of Electrical Engineering, IIT Bombay, Powai, Mumbai 400076 Ph: 022-2576 4424, 089 765 983 96 Gandhian Young Technological Innovation Award - 2013 POSOCO Power System Award: PPSA - 2013 IITB PhD Executive Member - 2013-14 IITB SARC Core Technical Member - 2014-15 On Fri, Aug 22, 2014 at 2:15 PM, Priyanka Murali <[email protected]<mailto:[email protected]>> wrote: You will have to change the type of the bus when Q hits the limits. For this monitor the Q limit and when it hits write call a function for this. On Fri, Aug 22, 2014 at 2:07 PM, Gelli Ravikumar <[email protected]<mailto:[email protected]>> wrote: Dear Sir/s, I have gone through core load flow programs of MatPower such as gausspf.m and newtonpf.m. But, in these methods, I could not found any provision of switching the PV bus to PQ bus whenever the Q limits of PV bus not met in the duration of iterations. Please let me know your insights into it. -- with Regards ---------------------------------------------------- Gelli Ravikumar Research Scholar (Ph.D), Field Computations Lab, Dept. of Electrical Engineering, IIT Bombay, Powai, Mumbai 400076 Ph: 022-2576 4424, 089 765 983 96 Gandhian Young Technological Innovation Award - 2013 POSOCO Power System Award: PPSA - 2013 IITB PhD Executive Member - 2013-14 IITB SARC Core Technical Member - 2014-15
