Research on Parallel Regenerative Braking Control of the Electric Commercial Vehicle Based on Fuzzy Logic 2021-01-0119

Regenerative braking is an effective technology to extend the driving range of electrified vehicles by recovering kinetic energy from braking. This paper focuses on the design of the regenerative braking control strategy for a commercial vehicle which requires significantly larger braking power than passenger cars. To maximize the energy recovery while ensuring the braking efficiency of the vehicle and its braking safety, this paper proposed a fuzzy logic strategy for regenerative braking control, and a feasibility study was conducted for an electric van. The work includes in three steps. Firstly, state variables that significantly affect regenerative braking performance, i.e., vehicle speed, battery State-of-Charge (SOC), and braking intensity, are identified based on mathematical modelling of the vehicle system dynamics in braking maneuver. With the three state variables as control inputs, the fuzzy logic controller is then developed to allocate the required braking force to the mechanical brake and the motor brake. Finally, the feasibility of the proposed fuzzy logic control method is verified under C-WTVC and CHTC-LT conditions on a joint simulation platform built with MATLAB/Simulink and AVL CRUISE. Compared with two baseline strategies (the original strategy provided by OEM and the default strategy in AVL CRUISE). The proposed method is shown to be more effective because it can reduce the energy consumption to 16.77% under C-WTVC condition and 8.05% under CHTC-LT condition while providing sufficient braking force as required in the two driving cycles.