The performance of the rotatory eddy current brake device directly affects the safety of train operation. Based on the change of the electromagnetic field vortex source density during the operation of the rotatory eddy current brake device, for improving its safety and reliability, main structural parameters such as the air gap size, the thickness of the turntable, the magnetic permeability of the core, the magnetic permeability of the turntable, the electrical conductivity of the turntable, the different currents and the arrangement of the magnetic poles of the eddy current brake device was adjusted to improve the braking torque and reduce the weight by means of simulation and experiment.