A dual-effect quarter-vehicle model for structural-acoustic frequency band analysis of electronically controlled suspension

Electronically controlled suspension (ECS) and road noise cancellation (RNC) technologies are widely used in modern vehicles to improve ride comfort and in-cabin acoustic performance. Recent studies indicate that rapidly varying suspension control signals may induce additional high-frequency vibrations and structure-borne noise. However, most ECS studies mainly focus on vehicle dynamics below 20 Hz, while high-frequency vibration behavior remains insufficiently investigated. To address this issue, this study develops a quarter-vehicle model with a rigid-ring tire and a strut-mount bushing to investigate ECS characteristics over the 0–500 Hz range. A frequency-banded evaluation framework is established to analyze both low-frequency suspension performance (0–20 Hz) and high-frequency structure-borne vibration behavior (20–500 Hz). Experimental measurements are conducted to validate the proposed model. Simulation results show that, compared with the conventional quarter-vehicle model, the rigid-ring tire significantly strengthens vibration coupling within the 50–500 Hz band, increasing body vertical acceleration by 174.4%. In contrast, the strut-mount bushing reduces the vibration level by 14.0%. In addition, Linear Quadratic Regulator (LQR) control further amplifies rigid-ring-induced high-frequency vibrations. The influence of control frequency is also investigated, showing that insufficient control frequency may excite structural resonances within the 50–500 Hz range. The proposed model and evaluation framework provide a basis for full-band ECS analysis and improve understanding of the interactions among suspension structure, control strategy, and high-frequency vibration behavior.