To overcome the large power consumption, the braking torque heat recession, and installation difficulties for trailers of eddy current retarder (ECR), a novel self-excited, liquid-cooled, and bridge integrated retarder (SLB-EMR) is proposed in this paper. The structure and work principle of the SLB-EMR are described particularly. Based on the magnetic equivalent circuit (MEC) method, an analytical model of the eddy current braking torque considering magnetic flux leakage and end effect is established. The power generation and braking performance of the SLB-EMR are predicted by the finite element analysis (FEA). We carried out tests for the eddy current braking torque, the heat-fade of braking torque, the no-load loss torque, and natural characteristics of the SLB-EMR respectively. The test results showed that the eddy current braking torque reached 2592 N·m at 1000 r/min. The braking torque declined by 15.5 % after the braking 12 min continuously. The analytical model of eddy current braking torque, and FEA model of the generator and eddy current brake were verified by the test. Compared with the ECR, the SLB-EMR had no-power consumption and low head-fade.