Thank you for the clarification. I appreciate. On Mar 11, 2013 5:51 PM, "Ray Zimmerman" <[email protected]> wrote:
> By default the cost of reactive power provided by generators is zero in > MATPOWER. However, this does not mean that the nodal price of reactive > power is necessarily zero. Nodal prices are sensitivities of overall > objective function value to an incremental change in load at the bus. > Because of the fact that an incremental change in reactive load at a bus > may require a redispatch, with some associated cost impact, of active > power, the reactive power nodal price can be non-zero even if all reactive > power generation is free. This will happen at buses where the corresponding > generator is at a reactive limit, or if there is no generator at the bus. > > The computation of the prices themselves are handled by the individual > solvers. Each solver computes the dual variables in according to its own > algorithm. > > -- > Ray Zimmerman > Senior Research Associate > 419A Warren Hall, Cornell University, Ithaca, NY 14853 > phone: (607) 255-9645 > > > > > On Mar 11, 2013, at 2:51 AM, muisyo irene <[email protected]> wrote: > > Hi, > > > I am a student in Jomo Kenyatta University of Agriculture and Technology > (JKUAT), in Kenya – Africa. > > > I am doing my research on nodal pricing (using MATPOWER) and I’m writing > to get more information on how nodal prices are obtained, especially for > reactive power.I have run the AC OPF, got the results but I want to > understand how they are arrived at. For example in case6ww, the quadratic > cost of P is given, hence Lambda can be obtained, but the cost of Q is not > given. I looked at grad_copf and fun_copf but it’s still not clear to me. > > > Kindly assist. > > -- > Regards, > Irene Muisyo > +254 721 332 377 > > >
