Generalised computer program for power-system analysis

The paper gives details of a set of power-system analysis programs based on a common-input array and on a common-impedance-matrix form of solution. The latter has enabled all the conventional items of analysis, and also relay performance, to be integrated into one program, yielding maximum computer efficiency and minimum data handling. This is described in the first section of the paper. The next section develops the theory to indicate how the usual machine approximations can be replaced by more detailed representation, still within the frame work of the matrix method. Also described here are the means by which the effects of governors, voltage regulators, induction-motor loads and other nonlinear devices can be included. The last two sections of the paper show how this analysis is extended to large power systems, using `tearing¿ techniques, and how unbalanced fault calculations are carried out. Throughout the paper, the authors illustrate the way in which the programs have been written as a tool for practising engineers, and not as a substitute for them.