作动器惯性质量对主动悬架幅频特性的影响

Influence of Inertia Mass in Actuator on Amplitude-frequency Characteristics of Active Suspension System

设计了一种用于车辆主动悬架的齿轮齿条式作动器,并探究作动器惯性质量对主动悬架幅频特性的影响。首先给出了惯性质量的计算方法,分析了惯性质量对悬架系统固有频率的影响,接着,进一步对比了被动悬架、引入惯性质量、施加天棚控制和施加加速度阻尼控制4种情况下悬架3个评价指标的传递特性。最后通过台架试验进行了验证。结果表明:惯性质量的引入降低了车体和车轮固有频率,改善了中低频区域的振动,但加剧了高频区的振动;天棚主动控制只能改善中低频区域的振动抑制效果,但导致高频区振动的恶化;而加速度阻尼控制能减小惯性质量对中高频区域振动的恶化,相对较好地提高中高频区域的振动抑制效果。因此,作动器含有惯性质量的主动悬架系统应选择中高频控制效果较好的加速度阻尼控制算法。

A rack-pinion type actuator for vehicle active suspension is designed, and the influence of actua-tor inertia mass on the amplitude-frequency characteristics of active suspension system is investigated. Firstly the cal-culation method of inertia mass is given and the effects of inertia mass on the natural frequency of suspension systemare analyzed. Then the transfer characteristics of three evaluation indicators of suspension system in four situations,i.e. traditional passive suspension, suspension with inertia mass added, suspension with inertia mass and skyhook（SH） control and suspension with inertia mass and acceleration damping driven （ADD） control are compared. Fi-nally bench tests are conducted for verification. The results show that the adding of inertia mass reduces the inherentfrequency of car body and tire, and hence improves the vibration in middle-low frequency region but aggravates thevibration in high-frequency region. SH control can only improve the vibration suppression effects in middle-low fre-quency region but aggravate the vibration in high-frequency region, while ADD control can alleviate the aggravationof vibration and relatively better enhance vibration suppression effects in middle-high frequency region. Therefore theactive suspension system with actuator inertia mass should select ADD control algorithm with better vibration sup-pression effects in middle-high frequency region.