Control of the Vehicle Inertial Suspension Based on the Mixed Skyhook and Power-Driven-Damper Strategy

With the development of the traditional semi-active suspensions, different kinds of control algorithms have been proposed and applied, including skyhook (SH), acceleration-driven-damper (ADD), power-driven-damper (PDD), the mixed SH and ADD (SH-ADD), mixed SH and PDD (SH-PDD), and others. Among them, the vibration suppression in a wide frequency domain is realized by the SH-ADD or the SH-PDD, but the latter is more effective. Subsequently, the vehicle inertial suspension has been found to have better vibration suppression performance than the conventional suspension in the low frequency band. In order to suppress body vibration in a wide frequency domain to improve overall ride comfort, the inertial suspension using SH-PDD is proposed to further improve the vibration isolation performance due to its superiority of low frequency resistance in this article. First, an inertial suspension model of SH-PDD strategy is established, and the superior characteristics of an inertial suspension in a low frequency range are verified in numerical analysis. Then, the impact of the damping coefficient of the SH-PDD control strategy on the dynamic output performance of an inertial suspension is studied. In addition, the parameters of the proposed inertial suspension are optimized by means of the particle swarm optimization (PSO) method. By designing the error dynamic equation and sliding mode switching function, a sliding mode variable structure controller for an inertial suspension is finally constructed. Simulation results show that compared with the SH-PDD conventional suspension and the conventional suspension, the RMS value of body acceleration of the SH-PDD inertial suspension is reduced by 16.6% and 32.2% respectively, and the reduction is mainly in a low frequency range. Therefore, the proposed inertial suspension possesses better attenuation ability for the vehicle body vibrations to improve ride comfort.