Akira Kishima

Solution of ill-conditioned load flow equation by homotopy continuation method

A homotopy continuation method is used to solve ill-conditioned load flow equations. It presents the predictor step effective for following the path of homotopy functions formulated from the load flow equation. The aim is to solve the ill-conditioned load flow equation, the solution of which has long been discussed. Using the homotopy method described, it is concluded that the ill-conditioned load flow equation discussed has no solution.<<ETX>>

A computation of power system characteristic by general homotopy and investigation of its stability

Presents an application of a general homotopy method to the computation of the characteristics of a power system such as PV curves. The load flow equations are derived from a set of nonlinear differential and algebraic equations. A homotopy continuation method is used for following the characteristics of the power system. The stability of the load flow solutions is discussed by deriving the variational equation.<<ETX>>

Subharmonic oscillations in three-phase circuits

Abstract This paper analyzes the subharmonic oscillations generated in three-phase circuits by the asymptotic method. As the result of the analysis, we find that there are three kinds of the 1 3 -harmonic oscillations, 1 3 -harmonic oscillation with beats, 1 3 -harmonic oscillation without beats and 1 3 -harmonic oscillation occurring in a single phase of the three-phase circuit. By means of an experimental circuit we confirm these oscillations.