Design of a Hybrid Electromagnetic/Hydraulic Damper for Automotive Suspension Systems

Vehicle suspension systems have been extensively explored in the past decades, contributing to ride comfort, handling and safety improvements. The new generation of power-train and propulsion systems, as a new trend in modern vehicles, poses significant challenges to suspension system design. Consequently, novel suspension concepts are required, not only to improve the vehicle's dynamic performance, but also to enhance the fuel economy by utilizing regeneration functions. However, the development of new-generation suspension systems necessitates advanced suspension components, such as springs and dampers. This paper presents the concept, design, and modeling of a novel hybrid electromagnetic/hydraulic damper for automotive suspension applications. This study indicates that the coupling of active/passive systems benefits the power consumption issue in active systems, while saving cost and weight. A potential hybrid damper design is proposed, where hydraulic damping effect is employed as a source of passive damping. The active part of the damper is designed to satisfy the required active force. The designed damper is analyzed under the steady-state conditions to determine the correlation between the passive damper performance and design parameters. It is demonstrated that a passive damping of similar to 1700 Ns/m can be achieved, by the addition of the viscous fluid to the active damper, which guaranties a fail-safe damper in case of power failure.