Multi-objective optimization of a hybrid excitation generator with a parallel magnetic circuit based on the coupling of dual optimization algorithms

The coaxial parallel magnetic circuit dual-rotor hybrid excitation structure generator exhibits several advantages, including high output performance, a wide adjustment range, and excellent stability. This study introduces a topology for a parallel magnetic circuit hybrid excitation generator (PMC-HEG) that utilizes a combination of permanent magnet and electrical excitation. It features salient pole rotors and claw pole rotors, with the latter embedded with permanent magnets, sharing a common stator. The analysis of the rotor magnetic field is conducted using both the equivalent magnetic circuit method and the subdomain method. Through an examination of the generator’s electromagnetic performance, key rotor parameters related to optimization objectives are identified. Finite element simulation analysis is performed on the rotor parameters, employing various optimization algorithms to enhance the salient pole and claw pole rotors, focusing on the amplitude of the induced electromotive force and the distortion rate of the induced electromotive force as optimization targets. The final optimized parameter values are obtained. A prototype is fabricated and tested, with experimental results confirming the reliability of the optimization method. The optimized parallel magnetic circuit hybrid excitation generator demonstrates an increase in the amplitude of the induced electromotive force, an improvement in the fundamental wave of the induced electromotive force, a reduction in harmonic distortion rate, and a significant enhancement in overall output performance.