Least Cost Transmission Expansion Planning considering N-1 Security Criteria using Discrete Water Cycle Algorithm

Transmission Expansion Planning (TEP) is a pivotal aspect of power system development, strategically locating, scheduling, and quantifying new transmission lines within the current infrastructure to meet future electricity demands. TEP involves a comprehensive analysis of technical, operational, regulatory, and economic considerations. Its chief aim is to harmonize a reliable power supply with cost-effective strategies for expanding the transmission infrastructure. TEP strives for efficient electricity supply, emphasizing security and reliability despite N-1 contingency criteria. Recent global blackouts have amplified concerns regarding power system security. Traditional TEP uses AC load flow equations, which can be complex for large-scale cases, leading to the adoption of less precise DC load flow models for computational efficiency. Numerous optimization methods, including mathematical and meta-heuristic approaches, have been explored to address TEP challenges, aiming for optimal solutions in line placement, expansion, and cost minimization. This study introduces an innovative approach, utilizing the Discrete Water Cycle Algorithm (DWCA) for TEP optimization, with a strong emphasis on integrating N-1 contingency criteria. The DWCA optimizes line placement and expansion plans while factoring in investment and operational costs. Its performance is enhanced by introducing stochastic selection of crossover and mutation operators. The efficacy of this approach is demonstrated on the Garver 6-bus test system. The results unequivocally exhibit the superiority of DWCA over other methods, resulting in cost reductions and the formulation of optimal transmission expansion plans. This study underscores the importance of DWCA in addressing TEP challenges and offering efficient, cost-effective solutions in the face of growing electricity demand and potential security criteria.