Cooperative control of regenerative braking and hydraulic braking of an electrified passenger car

TLDR

The paper investigates three control strategies—maximum‑regeneration‑efficiency, good‑pedal‑feel, and coordination—for regenerative braking in an electrified passenger car, aiming to balance regeneration efficiency and brake comfort. The authors model the regenerative and frictional braking components in MATLAB/Simulink, simulate and analyze the control strategies’ effects and regeneration efficiencies during typical deceleration, and validate the results with road tests under normal braking and an ECE driving cycle. Simulation and road‑test results indicate that the maximum‑regeneration‑efficiency strategy compromises brake comfort and safety, whereas the good‑pedal‑feel and coordination strategies improve both comfort and regeneration efficiency, achieving more than 25 % fuel‑economy gains under the ECE driving cycle.

Abstract

With the aims of regeneration efficiency and brake comfort, three different control strategies, namely the maximum-regeneration-efficiency strategy, the good-pedal-feel strategy and the coordination strategy for regenerative braking of an electrified passenger car are researched in this paper. The models of the main components related to the regenerative brake and the frictional blending brake of the electric passenger car are built in MATLAB/Simulink. The control effects and regeneration efficiencies of the control strategies in a typical deceleration process are simulated and analysed. Road tests under normal deceleration braking and an ECE driving cycle are carried out. The simulation and road test results show that the maximum-regeneration-efficiency strategy, which causes issues on brake comfort and safety, could hardly be utilized in the regenerative braking system adopted. The good-pedal-feel strategy and coordination strategy are advantageous over the first strategy with respect to the brake comfort and regeneration efficiency. The fuel economy enhanced by the regenerative braking system developed is more than 25% under the ECE driving cycle.