Experimental Eddy Current Retarder And Control Module Design

An eddy current retarder is an auxiliary continuous braking device independent of the main braking system and parking braking system of a vehicle. It cools wheel brake-staff and keeps brake-shoe in good condition by assuming 50～90 percent of total braking load. Besides, the eddy current retarder on a vehicle contributes to a smoother braking and a reduced level of noise and dust.First, the construct, working principles, and control method of an eddy current retarder are elaborated. A detailed introduction to the computational model from overseas and native relevant literature is also presented in this part, and analyse the problem of active computational model. Then the available methods for computing the braking moment of an eddy current retarder are compared by means of reverse verification, while factors affecting braking moment like the parameters of magnetic excitation coil, gap, and rotor size are analyzed. An experimental eddy current retarder is designed based on the project requirements following the analogue theory.The control methods for this eddy current retarder are examined, and a control scheme is decided based on the project requirements. A capable controller - the high performance micro controller P89C51RD2FA by Philips, is adopted, with its peripheral data acquisition and driver circuits optimized. The control circuits to eddy current retarder are drawn, and the controlling logic is programmed. Last, electronic-interference resistance measures are designed and applied.