A Load Flow Calculation Method for Ill-Conditioned Power Systems

In this paper, a load flow calculation method for ill-conditioned power systems is developed. The proposed method is very simple, has no mathematical approximations, and requires almost no additional storage and computation time when incorporated into the normal Newton-Raphson program. Using the method, the load flow solution never diverges, and also the existence of the solution from the initial estimate can be easily judged. To examine the effectivenesst two ill-conditioned power systems, i.e., 11 and 43 bus systems are studied by the method, and it is found that the solution does not exist for the 11 bus system though the given data are said to be operational, and also that the solution does exist for the 43 bus system but does not converge with the single precision due to the precision deficiency of the computer.