Comparison of Power flow methods for Distribution Grids

To meet the increasing demand for electricity, the power sector has integrated the smart grid concept in the distribution network, therefore the conventional network has been updated from a passive network to an active one, which will lead to various challenges in power (load) flow calculations because of the unpredictable distributed generation, the high R/X ratios and the quickly changing loads variation. Therefore, in order to maintain the network stability, fast power flow solution is required in some applications in distribution operation, planning, of a power system. A comparison between the main different power flow methodologies used for the future distribution grids is presented in this paper. The objective is to illustrate the transmission and distribution grids characteristics and present a comparison between the main different power flow solutions algorithms for 3-phase unbalanced distribution grids which exploit the radial topological structure to reduce the number of equations, unknowns, and the numerical structure. The methodologies are classified into four main techniques; The Forward and Backward sweep technique, Compensation technique, Sequence components, modified Newton technique.