A Hierarchical Step-by-Step Multi-Objective Genetic Optimization for Multi-Port Composite Flux-Modulated Machines

This paper presents a hierarchical and step-by-step multi-objective genetic optimization method for the multi-port composite flux-modulated (MP-CFM) machine, aiming to propose a simpler and high-accuracy optimization strategy for such multi-port composite machines. As a specialized machine well-suited for hybrid power systems, the optimization design is innovatively conducted based on an analysis of the fundamental operating principles and working modes of the MP-CFM machines. Specifically, considering the complex structure of such composite machines, sensitivity analysis is employed, applying differentiated strategies based on parameter sensitiveness evaluation. Furthermore, to ensure the rationality of the optimization results, and also to reduce computational cost and improve convergence, the optimization is artfully developed hierarchically with multi-steps, in accordance with the multi-modes of the machine. Specific optimization objectives and variables are defined, respectively, for each mode to enhance the optimization efficiency. Finite element analysis results demonstrate the effectiveness of the proposed optimization strategy for such MF-CFM machines for hybrid power system applications.