Optimized Braking Torque Generation Capacity of an Eddy Current Brake With the Application of Time-Varying Magnetic Fields

Unlike conventional hydraulic brakes (CHBs), eddy-current brakes (ECBs) are electrically controlled and noncontact-type actuators. Having such advantages makes ECBs a potential alternative to the conventional systems used in vehicles. However, the braking torque generation of ECBs at low speed is insufficient to stop the vehicle. Thus, such brakes are used for assistive braking. Our previous study showed that braking torque increases with an ac field application compared with the torque generated with a dc field application. To increase the braking torque generation to realize a stand-alone ECB, the braking torque generation of the ECB is optimized, using a stochastic search algorithm, with the consideration of comfort and skin effects, as well as geometric and field-dependent factors. The results show that the application of an ac field with varying frequency on a configuration with multiple pole projection areas (PPAs) results in a significant increase in the braking torque compared with the dc field application, and such optimum ECB configuration can generate a sufficient amount of braking torque comparable with those generated by CHBs.

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