目前市面上運用線型馬達於懸吊系統中的有美國Bose公司所開發的“Bose懸吊系統”。此系統利用音圈馬達取代避震器及圈狀彈簧,其優點在於反應時間較液壓式致動器短,並可隨路面狀態調整致動力以達到更好的操控性及舒適性。但音圈馬達力量常數較小,故體積較大且須消耗較多的電能。 本文設計一組線型同步馬達安裝於圈狀彈簧內,在最大容許電流之下可達到5000(N)以上之馬達力,而線型同步馬達力量常數較大,故所需體積較小。本文之控制策略是使用LQR控制方式,再利用PWM訊號及電晶體開關來控制馬達電流,以達到控制器之要求。而為了提高控制效果,需準確的知道各相控制電流,故需要有精準的位置感測器。最後利用頻率響應圖,來分析被動式與主動式懸吊控制系統之優劣。
The Bose company applies Linear Motor with the suspension system which named by “Bose suspension system”. The system applies coil motor instead of absorber and spring . The response time of the system is better than hydraulic type. The system depends on the road state to improve ride comfort and to increase the handling stability for vehicle in driving. Because the force constant of the coil motor is smaller, so the system need bigger space to install and consume more electric energy. The paper designs linear synchronous motor which is installed with spring. The motor can be produced over 5000 N under the limit current. Because the force constant of the linear synchronous motor is bigger, so the system don’t need bigger space to install. The control strategy is based on LQR .The system uses PWM and switch transistor to satisfy the controller require. The system uses high sensitive position sensor in order to give accurate phase current of the motor and get better control effect. Finally, frequency response is analyzed to investigate advantage and disadvantage between the traditional suspension system and the active suspension system.