Static planning of the expansion of electrical energy transmission systems using particle swarm optimization

•Constructive Heuristic Algorithm applied to identify the relevant expansion routes.•This model reduces the search space.•To increase the efficiency of the bio-inspired particle swarm search process.•It was applied to the Garver system and South/Southeast Brazilian System.•It was found a more economical expansion plan than had been found before.

Static planning of the expansion of electrical energy transmission systems consists of determining, among a pre-defined set of candidate expansion circuits, which ones must be built to minimize the operational costs (deficit) and investment in the electrical system, supplying the predicted demand for a planning horizon. Considering this problem, the proposed methodology uses a Constructive Heuristic Algorithm (CHA) to identify the most relevant route from a set of candidate expansion routes to reduce the search space and, consequently, increase the efficiency of the bio-inspired particle swarm search process. Therefore, the proposed methodology is divided into two stages: (i) obtaining the reduced set of candidate expansion routes using the CHA to decrease the search space without losing relevant expansion paths; (ii) using particle swarm optimization and heuristic information from the first stage to find the minimum expansion cost of the transmission system. In both stages, the transmission system is represented by the linearized load flow model, where the expansion decisions are incorporated into the problem using the original equations of the DC model. The proposed methodology was applied to the Garver system and to two real equivalent systems for the South and Southeast of Brazil, where the efficiency of the proposed system can be verified.