Optimal layout of parallel power cables to minimize the stray magnetic field

This paper deals with three-phase power lines operated by parallel power cables. In these systems each phase is made up of several parallel subconductors and it is well known that the sequence of the subconductors influences the magnetic field generated by the power line. This paper proposes a new approach to identify the optimal arrangement of the power cables that minimizes the stray magnetic field. Unlike the design methods covered by the literature, this paper proposes a deterministic procedure that is based mainly on a simple geometrical indicator. This geometrical quantity makes it possible to analyze all the configurations in order to create a small subset of candidate solutions. From this subset the optimal solution is then identified quickly and easily by computing and comparing the stray field. A full validation of the proposed approach is performed by comparing it with a standard method based on genetic algorithm. The results of the validation also provide a useful table that covers all the cases from 2 to 6 subconductors for each phase. Furthermore, it is shown that the geometrical indicator makes it possible to obtain a good cable arrangement in a direct way, without performing any magnetic field evaluations.