Design of the Eddy Current Brake Arrangement for a Laboratory Dynamometer

Abstract

This thesis is about the design of an eddy current brake arrangement for a laboratory dynamometer. The brake is intended to load a three-phase induction motor and measure its performance characteristics. A radial-flux, DC-excited eddy current brake configuration is selected and analyzed using the finite element method. The electromagnetic model is built and simulated in ANSYS Maxwell 2D. Simulations are performed for three disc materials — copper, aluminum, and mild steel — at excitation currents ranging from 0.5 A to 5 A at a rotor speed of 1000 rpm. The braking torque is recorded and compared for each material. Results indicate that the aluminum disc produces the highest braking torque of 99.56 Nm at 5 A, which is approximately 26% higher than copper and twenty-nine times higher than mild steel. The effects of pole number, pole shape, air-gap length, and disc thickness on braking performance are also investigated. The optimal design uses a 4-pole structure with a 2 mm aluminum disc and 1 mm air gap. Compared with other disc materials, aluminum offers the best combination of braking torque, weight, and cost for laboratory dynamometer applications.