Abstract:This paper focuses on the reliability of distribution network which is accessed by distributed generation(DG), and establishes an optimal configuration model based on reliability indicators to solve the problem of reliability analysis of the distribution network. According to the characteristics of the grid with DG, this paper simplifies the distribution network to a system which takes autonomous control units(ACU) as the main component. Then the power grid is divided and classified into autonomous control regions(ACR) and calculates the reliability indices of different classes of ACR. And through the reliability index to establish an optimization model, eventually configure the system''s DG capacity. Through the analysis of practical examples, the proposed method can correctly calculate the reliability index of the system, and replace the reliability index of the load with the ACR index, which reduces the computational complexity from the calculation amount and is faster than the traditional method. Therefore, the reliability analysis and optimization configuration method of distribution network based on autonomous units is more suitable for the current large-scale access to distributed energy systems, and provides an effective means to solve the problem of reliability calculation of distribution network.