Eddy current brakes (ECB) utilise electromagnets to generate smooth braking torque in contrast with traditional friction braking. A disadvantage is the low braking forces experienced at low speeds and as a consequence, the moving object never ceases its motion. The aim of this research is to develop and construct an electrically controlled ECB for research on an application specific motor at Charles Darwin University (CDU). A literature review was conducted into previous works on ECBs and three theoretical models were identified. Between the models Schieber, Smythe and Wouterse, the Wouterse method appeared most appropriate as it is both simple and applicable for this application. The determination of the magnetisation curve of the core material provides the characteristics required to design the ECB. The load line was determined for specific currents to provide a theoretical flux density in the air gap. These values were also confirmed experimentally. The design indicated that in order to achieve the required specifications and constraints, a large number of turns and core would be required. The final constructed design was tested using the permanent magnet synchronous motor (PMSM) at CDU to confirm the simulated torque, speed and current values. In order to confirm the flux travelling through the air gap, a Gaussmeter was used to experimentally measure the flux. The results for the torque versus speed was collected using Labview. This provided torque and speed readings through a torque sensor and incremental encoder. As the aluminium disc did not completely occupy the cross sectional area of the core’s air gap, the results confirm that in order to achieve the simulated results, the current required will need to be increased.
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