Transmission and substation expansion planning using Mixed Integer Programming

This paper presents a novel planning approach which optimizes size and location of new transmission substation (TS) investments considering capacity expansion of the existing TSs based on primary distribution network investment requirements. Mixed Integer Programming (MIP) is utilized and the problem is decomposed into investment and feasibility check subproblems. The algorithm is formulated to minimize total investment cost while supplying the spatial forecasted load considering a set of system constraints. The results of two numerical examples indicate that presented algorithm is adequate for determining requirements of new transmission substations and/or capacity expansions together with new HV/MV lines, via appropriate selection of candidates. Visualization of the planning algorithm results, in an iterative manner, gives very important verification signals regarding the necessity of the proposed investments.