Research On Regenerative Braking Strategy Of Parallel Hybrid Electric Vehicles And Its Influencing Factors

Hybrid cars, transitional products between internal-combustion engine vehicles (ICEVs) and pure electric vehicles, would be the main products in automobile works. This is because they alleviate the serious crisis of oil shortage and environmental pollution caused by ICEVs and because they address the storage problems of cells in electric cars at the same time. The Regenerative Braking System plays an essential role in the automobile performance. Thus, problem appears in reasonably allocating the shares of mechanical and regenerative braking force and simultaneously recovering braking energy.Revised ideal and parallel braking force distribution straregies were proposed after ameliorating the existing ones. The novel ideal ones, including front wheel drive, rear wheel drive and four wheel drive patterns, are suitable for brake-by-wire systems; while the novel parallel ones, including passenger cars with front wheel drive pattern and commercial vehicles with rear wheel dirve pattern, are applicable in original brake systems with only few modifications. Braking models were built and simulated on the platform of MATLAB/Simulink according to the theoretical analyses. The results indicate that revised strategies can recover considerable energies and guarantee the braking distance synchronously.Additionally, three essential parameters which affect the recovery rate were discussed. These parameters are mixedness, pavement friction coefficient and driving type. The specific impacts on the revised strategies were analyzed theoretically. Then simulation models with certain parameters were simulated respectively, thereby verifying the conclusions deduced by theoretical analyses.