Optimal Coordinated Configuration of Distributed Generations and Sectionalizing Switches Using Bi-level Programming Approach

To improve both system reliability and voltage profiles in distribution networks requires the simultaneous installation of distributed generations (DGs) and sectionalizing switches (SSs). This paper builds a bi-level programming model for the coordinated configuration of DGs and SSs. The upper-level problem is to minimize the total investment cost of DGs and SSs and the penalty cost of power shortages, and the lower-level problem is to minimize the voltage deviation during typical operation mode. To explicitly represent the relationship between the penalty cost of power shortages and installation locations of DGs and SSs, an analytical expression of the failure rates of load nodes with respect to installation locations of DGs and SSs is derived. The bi-level model can be transformed to a mixed-integer nonlinear programming problem by applying the Karush-Kuhn-Tucker theorem because the lower-level problem is a quadratically constrainted linear programming problem. Case studies on an IEEE 33-bus distribution system is used to verify the effectiveness of the proposed method.