many thanks Eng. Mahmoud abdallah Teaching Assistant Ain Shams University Faculty of Engineering
On Tuesday, February 18, 2014 12:08 PM, Ray Zimmerman <r...@cornell.edu> wrote: You cannot specify both reactive power and voltage. You must specify one and solve for the other. The ENFORCE_Q_LIMS option that Shri mentions simply indicates to the program that you want to change your mind about which one you are specifying in the case where a reactive power limit will be violated by specifying V. -- Ray Zimmerman Senior Research Associate B30 Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On Feb 18, 2014, at 11:06 AM, Abhyankar, Shrirang G. <abhy...@mcs.anl.gov> wrote: By default, power flow does not enforce gen. reactive power limits. But you can use the option ENFORCE_Q_LIMS from the mpoption options database to set limits on the reactive power generation. Do help mpoption for more info. Shri From: Mahmoud Abdallah <mahmoud_abdallah2...@yahoo.com> Reply-To: MATPOWER discussion forum <matpowe...@list.cornell.edu> Date: Tue, 18 Feb 2014 05:00:50 -0800 To: MATPOWER discussion forum <matpowe...@list.cornell.edu> Subject: Re: ask in matpower >dear sir >I don't want specify reactive power >I only want the change in reactive power should be negative value > > >thus I try to put the limit of reactive power generated from bus 37 to be >only negative for example >from -4.4 to -4 > > >but power flow not consider this limits > > >what I can do to make the reactive power generated from bus 37 to be negative >values >(not fixed but change in a range of negative values ) > > >thank you in advance >Eng. Mahmoud abdallah >Teaching Assistant >Ain Shams University >Faculty of Engineering > > > > >On Friday, February 14, 2014 10:33 PM, Ray Zimmerman <r...@cornell.edu> wrote: > >The point of my previous post was that the power flow was doing what you told >it to (assuming I was correct about you specifying it as a PV bus). If you >want the power flow to solve for the voltage at the bus, given a specified >reactive power injection (which is what you seem to be expecting), then you >have to specify that by changing the BUS_TYPE to PQ in the input data. > > > > > > >-- >Ray Zimmerman >Senior Research Associate >B30 Warren Hall, Cornell University, Ithaca, NY 14853 >phone: (607) 255-9645 > > > > >On Feb 14, 2014, at 2:35 AM, Mahmoud Abdallah <mahmoud_abdallah2...@yahoo.com> >wrote: > > >>dear sir >> >> >>this bus has wind thus it can't produce reactive power >> >> >>all reactive power comes from the network to bus 37 >> >> >>thus the reactive power in the power flow output should be negative at bus >>37 >>Eng. Mahmoud abdallah >>Teaching Assistant >>Ain Shams University >>Faculty of Engineering >> >> >> >> >>On Friday, February 14, 2014 12:53 AM, Ray Zimmerman <r...@cornell.edu> wrote: >> >>Presumably it is specified as a PV bus, which means that you are asking the >>power flow program to solve for the reactive power required to maintain the >>specified voltage magnitude. >> >> >> Ray >> >> >> >> >> >> >>-- >>Ray Zimmerman >>Senior Research Associate >>B30 Warren Hall, Cornell University, Ithaca, NY 14853 >>phone: (607) 255-9645 >> >> >> >> >>On Feb 13, 2014, at 5:36 PM, Mahmoud Abdallah >><mahmoud_abdallah2...@yahoo.com> wrote: >> >> >>> dear sir >>> >>> >>>I use case 39 which has wind at bus 37 >>> >>> >>>the wind at bus 37 has positive active power and negative reactive power >>> >>> >>>but when I use "runpf" with change in active power to be 1.5 * its old >>>value >>> >>> >>>I find that reactive power (of bus 37) in the result of power flow becomes >>>positive ??? how >>> >>> >>>Eng. Mahmoud abdallah >>>Teaching Assistant >>>Ain Shams University >>>Faculty of Engineering >>> >> >> >> > > >
