Probabilistic Techniques in Load Flow Analysis — A Practical Application

ABSTRACT The load flow analysis is undoubtedly the most useful study made for designing and operating power systems. The necessary input data for these studies are better described by random variables considering the probabilistic nature of loads, generation and network. The effects of these uncertainties on the steady-state behaviour of power systems are evaluated by a stochastic or probabilistic load flow (PLF) analysis. This paper presents an overall view of the PLF problem and methods of solution. Also, in order to illustrate the main features of the probabilistic analysis over the conventional one, the PLF technique is applied to a part of the brazilian system (69/138 KV network with 84 busbars) to provide adequacy indices for the operation planning phase. Details on the collection and modelling of probabilistic data, utility's operating policy and other constraints of the studied system are included.