Abstract
This paper addresses the phase-balancing problem in three-phase power grids with the
radial configuration from the perspective of master–slave optimization. The master stage corresponds
to an improved version of the Chu and Beasley genetic algorithm, which is based on the multi-point
mutation operator and the generation of solutions using a Gaussian normal distribution based on the
exploration and exploitation schemes of the vortex search algorithm. The master stage is entrusted
with determining the configuration of the phases by using an integer codification. In the slave stage,
a power flow for imbalanced distribution grids based on the three-phase version of the successive
approximation method was used to determine the costs of daily energy losses. The objective of the
optimization model is to minimize the annual operative costs of the network by considering the daily
active and reactive power curves. Numerical results from a modified version of the IEEE 37-node
test feeder demonstrate that it is possible to reduce the annual operative costs of the network by
approximately 20% by using optimal load balancing. In addition, numerical results demonstrated
that the improved version of the CBGA is at least three times faster than the classical CBGA, this was
obtained in the peak load case for a test feeder composed of 15 nodes; also, the improved version
of the CBGA was nineteen times faster than the vortex search algorithm. Other comparisons with
the sine–cosine algorithm and the black hole optimizer confirmed the efficiency of the proposed
optimization method regarding running time and objective function values