Abstract: With the high proportion of distributed photovoltaic accesses to the distribution network, how to plan the transmission line and how to locate and determine the capacity of the source-storage has become an inevitable problem. In this paper, a dual-layer joint expansion planning strategy on source-grid-load-storage of distribution network is proposed. The upper layer establishes a line planning model with the goal of minimizing annual investment cost and network loss penalty cost of the distribution network system, to achiev improvements in the direction of the distribution network lines; the lower layer in view of the uncertainty of source and load, the source-storage addressing and capacity setting model of the distribution network is established with the goal of maximizing the operation income of the distribution network, and the uncertainty parameters are introduced to constrain the range of the source-load uncertainty set. To solve the non-linear and difficult optimization problems in the proposed dual-layer planning model, the above non-convex and nonlinear optimal programming model is transformed into a second-order cone optimization model based on the second-order cone relaxation algorithm and then the global optimal solution is realized, so as to obtain the optimal access location and capacity of distributed photovoltaic and energy storage. The simulation results show that the proposed method can effectively reduce the planning cost of the distribution network and promote the consumption of distributed power source.

    Key words: active distribution network; distributed power source; second-order cone relaxation; dual-layer joint planning