Piecewise Power Flow Solution Using Impedance Parameters

Power system engineers are continually faced with the problem of handling large-scale networks
arising due to system expansion and greater interconnections. Large-scale systems can be solved using piecewise
solution technique wherein the original system is torn into several subsystems, each subsystem is solved independently
and the solutions of subsystems are tied up to obtain the total solution. In the proposed method, impedance
parameters are consistently used to solve power flow problem of large power systems. The inverse of the Jacobian
matrix of each subsystem is derived from the bus impedance matrix of that subsystem. The effect of the cut elements
are accounted through proper power injections. The proposed power flow method is successfully tested on IEEE
standard systems and found to give good results.