Abstract
The eigenvalue method is wellβknown as an aid to the solution of a wide range of engineering problems. In power system analysis it has relevance to travelling wave phenomena,^1^ sensitivity and dynamic stability in synchronous multimachine^2^ systems, critical speed calculation, vibration of structures and other related topics. The method of numerical solution of eigenvalues depends on the size and nature of the problem and often where large matrices are involved presents great difficulties.
This paper describes in detail the application of the escalator method and diakoptics to large eigenvalue problems. The escalator method is a wellβestablished one which consists of a systematic way of escalating from a 2 Γ 2 matrix up to any desired order in steps of one row and column at a time. The diakoptical method reduces computer storage, calculation time and improves accuracy. This results in the more economical solution of large and complicated problems which cannot be conveniently solved by any orthodox method. The paper deals with problems of degeneracy and means of overcoming these by simple routine processes. It concludes by indicating the particular advantages of the method and its usefulness for a wide variety of general engineering problems.