Comparison between Interval and Fuzzy Load Flow Methods Considering Uncertainty

This paper presents a power flow algorithm to carry out load flow by analysing uncertainties. The proposed algorithm is compared with Fuzzy arithmetic to deal the effect of uncertainity. The proposed method is Interval load flow i.e. Interval Improved Fast Decoupled Power Flow (IIFDPF) that considers input parameters as interval variables and considered method is trapezoidal method have been employed to solve the uncertainties in load flow analysis where LR (left-right) fuzzy arithmetic have been applied to model the uncertainties. Uncertain parameters are treated as fuzzy numbers with given membership functions. Both techniques are tested on a typical Load flow solution, considering loads and generator are as uncertain. In order to provide a basis for comparison between above two approaches the shapes of the membership function used in fuzzy L-R as inputs and same range of uncertainty consider in interval method . Interval method provides better output results compared to Fuzzy L-R method. The IIFDPF algorithm is validate with INTLAB toolbox /MATLAB environment using the IEEE standard test data. Keywords— Interval arithmetic, Interval Improved Fast Decoupled, Interval Newton’s method, Fuzzy load flow