Reducing the number of candidate lines for high level Transmission Capacity Expansion Planning under uncertainties

Creating an appropriate candidate lines list (CLL) is critical for Transmission Capacity Expansion Planning (TCEP), and it will affect both the optimal answer and computational time. In this paper, we propose a systematic way to reduce the size of CLL in early steps of high level TCEP, in which the number of primarily proposed candidate lines is large. In the proposed algorithm, after detecting important lines in the base case system for monitoring, the impact of adding different candidate lines on selected important lines is evaluated by using Line Closure Distribution Factors (LCDFs). Lines such that their closure will have negative impacts on congested lines will be removed from CLL. Applying the proposed heuristic method on ERCOT network shows its effectiveness on decreasing computational time for TCEP.