Research on Braking Performance of a Novel Variable Magnetic Circuit Eddy Current Retarder

To address the limited braking performance of conventional eddy current retarders (ECRs) across the full speed range, a novel variable magnetic circuit eddy current retarder (VMCECR) is proposed by integrating alternating magnetic field braking and pulsating magnetic field braking. The structure and working principles of the VMCECR are introduced, and a corresponding control strategy is developed. The transient magnetic field distribution, air-gap flux density under various excitation currents and speeds, and braking torque characteristics under different operating conditions are analyzed using the finite element method (FEM). Experimental validation is conducted through prototype testing on a dynamometer bench. Results demonstrate that the VMCECR achieves significantly improved braking torque across the full speed range compared to conventional designs.