Parameter-free hybrid RAO algorithm for reactive power optimization.

The Rao algorithms are a relatively new parameter-free optimisation technique that has grown in importance as an intelligent optimisation tool. Rao algorithms are effective algorithms that embody the idea of attracting toward a global optimum, illustrating the algorithm's swarm intelligence and the survival of the fittest principle, like that of an evolutionary algorithm. However, it has found applications in other areas related to optimization, primarily in engineering practice, where it is analyzed and summarized based on the specifics of each situation. The absence of algorithm-specific parameters explains the wide applicability of Rao optimization. Although several studies have addressed these methods, limited effort has been made to provide a comprehensive summary of Rao algorithms. This work aims to provide up-to-date information on Rao algorithms, which will be useful for researchers in this field. Additionally, a hybrid Rao algorithm is developed to overcome the limitations of traditional Rao algorithms. The proposed algorithm was implemented in the IEEE 30-bus and IEEE 57 bus systems, to resolve the Optimal VAR Dispatch Problem, and to assess its effectiveness. Results show that hybrid Rao algorithm deliver higher quality solutions within a reasonable timeframe, outperforming other approaches stated in the recent literature. The paper ends with recommendations for future developments to improve the Rao algorithm's performance.