傳統的半主動式懸吊系統之可調阻尼件為可變孔口液壓缸,其缺點為系統時間常數較長。本研究探討以音圈馬達取代液壓缸的可行性。利用車子懸吊系統之速度使音圈馬達產生反電動勢,然後利用其反電動勢來控制音圈馬達的作動力以消耗車輛的振動能量。 首先利用有限元素分析,求得音圈馬達之磁通量、力量常數、反電動勢常數…等。在控制器策略部分,利用LQR(Linear Quadratic Regulator)最佳化控制方式設計控制器,再利用鋸齒波控制及馬達控制來調整馬達電流,進而達到控制器所需之作動力,最後比較鋸齒波控制及馬達控制二種控制方式與被動式懸吊系統在不同頻率下之動態響應。
The adjustable damper of a semi-active suspension system is usually a hydraulic cylinder with variable orifice, but the time constant of a hydraulic cylinder is longer than an electric motor. This research investigates whether a voice coil motor (VCM) can replace the hydraulic cylinder as an adjustable damper. Basically, the back-electromotive force can be generated by the motion of the suspension stroke in a suspension system. The back-electromotive force is then used to produce motor output force by shorting circuit or adding a resistor to consume vibration energy. We establish a 2-D model of VCM and obtain the parameters by finite element analysis software. The adjust strategy of damper constant in suspension system is based on Linear Quadratic Regulator. Then, sawtooth wave control and motor control are used to adjust motor current. They can achieve output force of controller request. Finally, we compare two control methods of semi-active suspension system and passive suspension system in different frequency responses.