Design, analysis and real time dynamic torque control of single-rotor–single-stator axial flux eddy current brake

This study presents design, analysis and real time dynamic torque control of a single-rotor and single-stator axial flux (AF) eddy current brake (ECB). Design of the AF-ECB is accomplished based on magnetic equivalent circuit (MEC) modelling. Influence of the key design parameters on braking torque including permeability and resistivity of the disc material is also investigated. Braking torque profile of the AF-ECB is obtained by MEC modelling and numerical analyses are carried out by three-dimensional (3D) finite element analysis (FEA) to validate the MEC modelling and to obtain the braking torque profile. 3D magneto-thermal FEA are also completed to identify working period at maximum braking torque. A prototype AF-ECB is manufactured based on the analyses, and open-loop torque profile is experimentally verified. Good agreement between the test, FEA and MEC results is achieved. A real time controller is developed and dynamic torque control of the brake for various torque and speed references is also obtained to illustrate the dynamic behaviours of the system.