Research Of The Eddy Current Retarded Controller For Automobile

Eddy currency retarder, a kind of auxiliary braking device, undertakes 50%-90% of the braking work, which lowers greatly the temperature of the wheel braking device, reduces the load of the automobile's main braking device and improves its braking efficiency and stability. In recent years, eddy currency retarder has been introduced into China and applied into practice. China has started to research and develop the braking device with proprietary intellectual property right. This thesis does some research on the design of eddy currency retarder in the field of automobile in our country.This thesis analyzes the automobile's braking at first, and then induces the necessity of the installation of eddy currency retarder. What's more, it also elaborates the working principles, the structure and controlling ways of Eddy currency retarder, as well as the results of using it. The thesis aims to finish the work as the following. The first part puts up with the calculating method of the braking moment of force of eddy currency retarder based on the existing research results, then deduces the corresponding relationship between the braking force and field current and ensures the maximal output current of braking device. Next, according to the research on the eddy current retarding controller, it brings forward the design proposal of eddy currency retarding controller based on the controlling way of PWM and its detailed design ideas. In the process of the design, by emulating the parallel connection of power MOSFET, it analyzes the various factors which can affect the MOSFET current of parallel connection, and takes some measures to improve the circuit. Finally, some laboratories are done in the test station of the combination functions of eddy currency retarder, which verifies the functionality and reliability of the braking controller.