Distributed Firefly-Based Sensor Placement for Observability Enhancement in Power Transmission Networks

Abstract

Power transmission networks rely on geographically dispersed measurements to support state estimation, contingency analysis, and real time security assessment. The placement of phasor measurement units and complementary sensors strongly affects the degree to which system states can be reconstructed from available data. Classical placement formulations often assume centralized coordination and focus on static, single snapshot optimization, which can limit scalability in large interconnected systems operated by multiple control entities. Metaheuristic optimization has been explored to reduce computational effort, but many existing approaches remain centrally orchestrated and do not explicitly reflect the communication locality imposed by realistic grid architectures. This work investigates a distributed optimization framework for sensor placement, based on a spatially decomposed variant of the firefly algorithm. The approach embeds a linearized observability model derived from topological and measurement coverage relations into a binary optimization problem. Local agents associated with buses or control areas coordinate through neighborhood interactions that emulate firefly attractiveness and random perturbations. The resulting method seeks feasible sensor layouts that improve observability margins, enhance redundancy under line and sensor contingencies, and distribute measurement responsibility across the network. The study discusses modeling aspects, distributed algorithm design, and qualitative performance characteristics under varying communication graphs and cost structures. Emphasis is placed on how local visibility of topology and measurement options influences convergence behavior and solution quality. The discussion highlights trade offs among observability, installation cost, and communication overhead, and outlines how the distributed firefly mechanism can be tuned to respect operational and organizational constraints in modern transmission systems.