Brake force sharing to improve lateral stability while regenerative braking in a turn. (February 2019) - Nanda Kumar, CS
In electric and hybrid vehicles, regenerative braking is applied only at the driven wheels by the electric drive, whereas the non-driven wheels are not subjected to brake force during the pure regenerative braking mode. The application of pure regenerative brake may affect the vehicle's lateral stability during a turn. The impact could be more severe when the pure regenerative brake is applied at the turn on the rear wheels (for a rear wheel drive vehicle) over a low friction road surface. As part of a solution to reduce this impact, a brake force sharing (BFS) strategy between regenerative and friction brake has been proposed in this paper, which improves the brake force distribution between front and rear wheels to ensure a stable turn. The vehicle model and the BFS strategy were developed, and the IPG Car Maker® software was used to evaluate the effectiveness of the proposed strategy. The simulation results on BFS strategy have been corroborated using experimental data collected from a test vehicle. Further, a closed loop control structure was developed for implementing the proposed BFS strategy in electric and hybrid vehicles.