Rapid Design of Litz Wire Using Surrogate-Assisted Optimization Embedding Adjacent Trust Region

Abstract

Litz wire is essential in minimizing eddy losses in high-frequency power devices. However, accurately evaluating Litz wire impedance is challenging due to the low precision of analytical methods and the high-computational demands of numerical simulations. To address this, we propose a multifidelity surrogate-assisted optimization framework embedding with an adaptive trust region (MF-TR-SAO) that efficiently designs Litz wires through numerical simulation. This approach merges multifidelity modeling with space mapping (SM) to rapidly achieve global optimization. We validate the framework’s performance using Zakharov and Ackley functions and demonstrate its superiority over other optimization techniques. The MF-TR-SAO is then applied to the design of Litz wires comprising hundreds of strands. The optimized Litz wire design exhibits an 18%–36% performance enhancement in terms of power loss reduction compared with a conventional single-bundle wire while also considering cost-effectiveness and computational efficiency. This algorithm significantly advances Litz wire manufacturing by optimizing for power loss, cost, and design speed.