The Control Study of Vehicle Active Suspension with Electro-Hydrostatic Actuator

Abstract

Actuator is the key to vehicle active suspension. Based on the analyses of traditional passive suspension and active suspension system, a novel vehicle active suspension with Electro-Hydrostatic Actuator (EHA) is put forward. The system consists of two parts: spring and actuator with variable control force. The actuator is made up of hydraulic cylinder, hydraulic pump, controller and BLDCM. According to bond graph principles, bond graph model of 2 DOF passive suspensions and bond graph model of EHA active suspension are built. Moreover, fuzzy logic controller is designed and fuzzy control active suspension is simulated using MATLAB tools. The prototype and test rig of EHA active suspension are developed and bench tests are carried out. The simulation and experimental results show that fuzzy control active suspension with EHA provides better ride comfort, handling and stability than passive suspension.