A multiobjective H∞ control strategy for energy harvesting in regenerative vehicle suspension systems

ABSTRACT

A significant amount of energy induced by road unevenness and vehicle roll and pitch motions is usually dissipated by conventional shock-absorbers. In this paper, a novel active multiobjective ${\mathcal{H}}_{\infty }$ control design methodology is proposed which explicitly includes, besides the usual control objectives on ride comfort, road handling and suspension stroke, the amount of energy to be harvested as an additional, though conflicting, control objective and allows the designer to directly trade-off among them depending on the application. An electromechanical regenerative suspension system is considered where the viscous damper is replaced by a linear electrical motor which is actively governed. It is shown that the proposed control law is able to achieve remarkable improvements on the amount of the harvested energy with respect to passive or semi-active control strategies while maintaining the other objectives at acceptable levels. Simulative studies undertaken via CarSim are also reported that confirm the potentiality and flexibility of the proposed control design strategy.

KEYWORDS:

• Energy-harvesting
• suspension systems
• H-infinity control