Study on temperature rise performance of eddy current retarder in automobile

Good brake performance is an important guarantee for safe driving of vehicles. With the increase in vehicle weight and running speed the main braking system can not meet heavy vehicles and large passenger driven in the mountainous area and on long downhill requirements. Their brake load must be split flow by auxiliary brake set on continuous braking course, only in this way heat fading of main braking system can be avoided, and eddy current retarder is one of auxiliary brake sets. Heat energy that mechanical energy is converted into by electromagnetic field will make temperature rise in the rotor. According to conservation of energy principle and ECE R13 legislation temperature rise equation is derived on the rotor of eddy current retarder in this paper, and braking torque and temperature rise characteristics of eddy current retarder are researched by drum test and bed test. A shortcoming of electronic control temperature rise method is pointed out, and a new approach to solve above question is put forward.

I. Introduction

With the rapid development of highway driving speed of a vehicle is increasing and its braking load is growing continuously, the main braking system can not meet the requirements of safe driving [1]–[2][3]. Due to constraints of space structure and material properties improved brake design can not solve this problem at all, and the solution method is to split brake load by installing auxiliary brake now. In recent years, as one of auxiliary brake sets eddy current retarder is increasingly widely used, and because it is usually installed in the transmission braking forces passed to at left and right wheel are the same, so it don't make the vehicle dynamic deviation. When driving speed is low eddy current retarder has higher braking torque too, so this characteristic can improve vehicle brake safety.