Decoupled Semiactive Vibration Control of Electrically Interconnected Suspension Based on Disturbance Compensation

Electrically interconnected suspension (EIS) is an emerging technology for vehicle vibration control. This article proposes an acceleration-measurement-based disturbance compensation control strategy for vehicles with EIS. The EIS system has the decoupling characteristic, and it can achieve variable inertance and variable damping capability in the heave direction and variable stiffness capability in the roll direction. The EIS is interconnected with electrical components, providing more flexibility than mechanically and hydraulicly interconnected systems with similar versatile functions. In applying the EIS, accurately describing unmeasurable disturbances caused by friction forces, simplifying the model, and dealing with the nonlinearity of the electrical network pose challenges. Thus, this article introduces a disturbance observer that utilizes acceleration measurements in the heave and roll directions to estimate unknown disturbances in their respective directions. For each direction, the gains of the disturbance observer and
${\mathbf{H}}_\infty $
controller are obtained simultaneously using the linear matrix inequality method, which simplifies the implementation process. The control strategy utilizes the measured vertical acceleration and angular acceleration of the sprung mass to form a closed-loop feedback control, enhancing robustness. Finally, the effectiveness of the proposed disturbance compensation controller is demonstrated through experiments conducted on a half-car test rig. The results show significant improvements in vibration control compared to both passive suspension systems and EIS systems without disturbance compensation. The proposed observer is cost-effective and easy to implement in practice.