Most of the existing interval power flow calculation methods for distribution networks are based on the extension of iterative methods

which require multiple interval iterations to obtain convergence solutions

thus exist convergence problems and low computational efficiency. In this paper

a non-iterative affine inverse algorithm for interval linear three-phase power flow calculation of distribution network is proposed by the integration of linear three-phase power flow algorithm and affine inverse operation. In this method

the affine number is used to describe the correlation between interval variables

and the interval power flow equations are transformed into affine linear power flow equation

which are solved by inverse operation of affine matrix. The proposed method does not need iterations and have no convergence problem. Finally

several unbalanced power distribution systems are used to verify the performance of proposed method by the comparison with other three methods. The results show that the proposed method merits both in high computational efficiency and low conservation

as well as it has stable performance.