Design and Performance Analysis of Electromagnetic Suspension Based on In-wheel Motor Car

WANG Ruochen;YU Feng;SHAO Kai;MENG Xiangpeng;DING Renkai;CHEN Long;School of Automobile and Traffic Engineering,Jiangsu University;

WANG Ruochen%YU Feng%SHAO Kai%MENG Xiangpeng%DING Renkai%CHEN Long%School of Automobile and Traffic Engineering,Jiangsu University

in-wheel electric driving vehicle;;electromagnetic suspension;;sky-hook strategy;;tire grounding;;comfort

A structure of electromagnetic suspension with in-wheel motor was proposed. This structure was aimed at conquering the unsprung mass increase because of the motor in wheel to worsen tire grounding and ride comfort. In addition,this structure was equivalent to dynamic vibration absorber,which can effectively share the road vertical excitation on the tire. Thus,the dynamic model of the electromagnetic suspension was established with in-wheel motor. The transfer characteristics and the performance indexes( vehicle acceleration and tire dynamic load) between the quality systems were analyzed by simulation. The results showed that the suspension system can effectively inhibit the wheeltype formant during the frequency domain,and make the wheel-shaped resonant frequency avoid falling in the most sensitive section of the human body: 4 ~ 12. 5 Hz. Based on the structure,the actuator would use the sky-hook control strategy to improve the ride comfort. Compared with the conventional suspension,the body acceleration of new system was reduced by 23. 1%,and tire dynamic load was decreased by 16. 6%. In terms of modified structure and the sky-hook control strategy,the performance of ride comfort and tire grounding were improved obviously. Finally,the experiment was carried out on the single-aisle pedestals to verify the feasibility of the new structure and control method. The results showed that the negative effect of vertical vibration caused by the increase of the non-spring load of electric vehicle was suppressed by the new structure and new control method.