Abstract:

With the continuous increase of the proportion of distributed generations ( DG) in distribution grids,power systems face more and more challenges,such as the increase of uncertainty and the change of grid structure.The conventional load flow calculation method is unable to deal with such a great number of uncertainties in grids.In order to solve this problem,a probabilistic load flow calculation method based on the imperialist competitive algorithm ( ICA) is proposed,which can easily take into account all kinds of topology structures,different DG penetration levels and multiple constraint conditions of complicated networks,with good convergence as well.Moreover,for the purpose of improving the searching ability and convergence rate of the algorithm,a clone evolution operator is introduced in ICA.The modified IEEE-33 distribution system is used for simulation and the results are compared with those obtained via Monte Carlo simulation ( MCS) .It is found that the proposed method is of high precision and great practical value.

Key words: probabilistic load flow, smart distribution grid, distributed generation, imperialist competitive algorithm, clone evolution