Theory Study Of The Eddy Current Brake

With the development of the economy and the improvement of living standard, people have paid more attention to the safety of the vehicle. The eddy current brake is a third braking system,which can take on 50-90 percent brake work, and then cool the wheel clutch greatly. Using the eddy current brake can keep the wheel clutch in a satisfactory technology status, and make the car run more smoothly. In addition the noise decreases while braking. Firstly the dissertation represented the necessity of using the retarder, and introduced the eddy current brake, including the operating principle, the structure and the service performance. Next the paper showed the four parts work, which have been finished. On the foundation of predecessor's work, a calculation method of brake torque is brought forward in the first part, and then analyzed the effect of excitation coil parameter, air space, and plate dimension. The next three parts work is analysis of the magnetic field, temperature field, the stress of the eddy current brake bye using the CAE software ANSYS. In the analysis of the magnetic field, the APDL method is a good way to get the magnetic field. The intensity of the magnetic can be strengthened through adjusting the air space and excitation coil parameter. In the analysis of temperature, two cases, which one case is emergency braking and the other case is gradual braking, are considered. In the former case the maximum temperature reaches 207 degree Celsius, and in the latter case the maximum temperature reaches 334 degree Celsius. The temperature's rise brought some certain expansion, but the expansion affected less on air space, but brought larger thermal stress. In the analysis of the stress, the braking torque, the rotation speed and the temperature are all considered.