Hi Ray, Thank you for your kind response. I really admire you helping all us with our problems.
Actually no, I don't want to run OPF. I just want to run normal power flow rundcpf. I am aware of load2disp function. But I want to create my own load-shedding protocol. I want to curtail load in such a way that the power flowing through branches doesn't exceed its capacity, while at the same time curtail not too much such that the buses can partially fulfill their demand. Like I said, it is an optimization problem. I have the branch capacities for each of the branches. The power flowing through these branches must be less than these capacities - this is the constraint. So for a given branch capacity, I need to solve for the voltage angles, while at the same time maximize the objective function, which is the sum of loads. This will give me how much load was required to curtail to limit the power flow in the branches. My question is, how to solve for these voltage angles for a given power flowing in it? Is there a way to do it in the MATPOWER code? Best and thanking you, Bijay On Tue, Jan 12, 2016 at 7:03 PM, Ray Zimmerman <[email protected]> wrote: > It seems to me that you simply want to run an OPF (seems like you are > using a DC power flow model, so that would be rundcopf > <http://www.pserc.cornell.edu//matpower/docs/ref/matpower5.1/rundcopf.html>) > with your loads defined as dispatchable (curtailable) loads. See section > 6.4.2 in the MATPOWER User’s Manual > <http://www.pserc.cornell.edu/matpower/docs/MATPOWER-manual-5.1.pdf>. You > can use the load2disp > <http://www.pserc.cornell.edu//matpower/docs/ref/matpower5.1/load2disp.html> > function > to convert the loads. If the value of the loads is higher than the cost of > generation, then all load will be served unless load-shedding is required > to maintain feasibility. The OPF automatically enforces the line flow > limits. > > Ray > > > On Jan 11, 2016, at 5:56 PM, Bijay Hughes <[email protected]> wrote: > > Hi Ray, > > I have a scenario where a line fails, and this initially failed line > triggers more failures. This continues until the system experiences a > blackout. My plan is to prevent blackout by performing a load-shedding. I > have load-shedding protocol as an optimization problem. > > Objective Function: > > Maximize loads in the bus > > Constraint: > > Power flowing in the branches should be always less than the capacity of > lines. > > My question is how to control the power flow in the lines. I have the > capacity of lines. I guess I need to modify the powerflow code runpf.m or > makeBdc.m? But the question is which part? Given the capacity of lines, I > have to solve for the optimum voltage angles such that the load at the > buses is maximized. This will tell me how much load was needed to curtail > to minimize the cascading failure. The relation for voltage angles and > power flow is given by: Pf = BF * Va + PFINJ in makeBdc.m file. > > Any help would be greatly appreciated, Ray. I look forward to your > replies. > > Best, > > Bijay > > >
