Simulation research on braking performance of hydrodynamic torque converter and retarder based on automatic shifting rules

In this paper, an integrated procedure is developed in modelling and simulation of vehicle braking performance from a number of critical factors, which include vehicle-ground, engine, hydrodynamic torque converter and retarder (TC-R) and gearbox. In the technique development, a new application mode of TC-R, automatic shifting rules, is considered as braking strength which is affected by the gear state in the gearbox. Then two schemas of transmission are carried out in Matlab-Simulink simulations to initially test the model credibility and efficiency. The results show that to improve the braking performance of TC-R, the gearbox should shift to lower gear state as early as possible and an increasing-speed box should be added between the engine and the TC-R to protect the engine and maintain the braking performance.