Multi-objective optimal computer-aided engineering of hydraulic brake systems for electrified road vehicles

Abstract

Electrification of road vehicle powertrains involves significant re-design and re-sizing of foundation brakes. Both the usage and the size of hydraulic brake systems can particularly be reduced thanks to the contribution of regenerative braking torque supplied by electric motors, thus reducing cost and weight. In this work, a multi-objective optimal computer-aided engineering (CAE) methodology is proposed that allows designing hydraulic brake systems for electrified road vehicles. The achievement of requirements imposed by braking maneuvers concerning safety standards for brake systems represents a feasibility constraint for the design candidates within the proposed CAE workflow. A particle swarm optimisation (PSO) algorithm allows efficiently exploring the design space. Minimising the overall size of the hydraulic brake system and maximising the electrical energy recovered in the battery on average in everyday driving conditions represent the optimisation targets retained. A case study considering a battery electric vehicle (BEV) powertrain layout suggests the effectiveness and the flexibility of the developed CAE methodology in promptly identifying and assessing sub-optimal design alternatives for both front-wheel drive (FWD) and rear-wheel drive (RWD) arrangements. Furthermore, compared with the RWD option, the FWD powertrain layout appears considerably favorable for a BEV in terms of electrical energy recovering capability during braking.