Optimum HVAC-transmission expansion planning

Abstract

A new, flexible, mixed-integer formulation is presented for solving the single-stage AC-transmission expansion planning problem. This new formulation handles the discrete nature of equipment additions without resorting to linearized incremental approaches, but still uses integer linear programming. Even the interconnection of an initially disjoint system is handled directly without resorting to an arbitrary initially connected system. The optimal configuration at the end of the planning step under consideration minimizes an annually amortized cost function including the investment cost for equipment additions and the operating cost in terms of real-power transmission losses. Using a new, efficient, linear load-flow model, the formulation developed here is characterized by a complete decoupling between real and reactive equations. Examples have been incorporated to illustrate the potentials of this new optimum planning formulation. A major contribution of this paper is in showing how the power system transmission expansion planning problem can fit into the standard, mixed-integer, linear programming format in both a conventional sensitivity formulation and also with our new implicit enumeration formulation.