Investigation of the load-flow problem

A mesh approach is developed for the formulation of the network equations in load-flow analysis. It is shown to converge at least as fast as the usual methods using the nodal-impedance matrix. A hybrid approach is then developed, using a combination of an impedance-matrix method and a nodal-admittance-matrix method. The hybrid exhibits very fast convergence, and is the most powerful method encountered by the authors. It needs no optimum acceleration, and the number of iterations appear to be independent of system size and configuration. Finally, an investigation into the choice of an optimum swing/reference bus produced the only reliable criterion known to the authors.