Stochastic load flows

The load flow study has been at the center of studies made for designing and operating power systems for many years. It is well known that forecasted data used in load flow studies contain errors that affect the solution, as can be evidenced by running many cases perturbing the input data. This paper presents a method for calculating the effect of the propagation of data inaccuracies through the load flow calculations, thus obtaining a range of values for each output quantity that, to a high degree of probability, encloses the operating conditions of the system. The method is efficient and can be added to any existing load flow program. Results of cases run on the AEP system are included.