臺灣博碩士論文加值系統

本研究應用假設模態法(assumed-mode method)分析具主動葉片控制
之轉軸-圓盤-葉片系統的動態特性，同時探討當葉片受側向力時，轉軸的
扭振分析‧ 本文中以軸-圓盤系統與固定-自由葉
片系統之固有模態作為假設模態法之基底, 導出具壓電陶瓷控制葉片之轉
軸-圓盤-葉片系統之運動方程‧其中應用單一壓電陶瓷同時作為感測及致
動元件之原理,將壓電陶瓷結合於系統之葉片上,利用比例與導數回授控制
(proportional plus derivative feedback control,PD)理論,從壓電感
測器測得之壓電值,經PD控制增益放大後,輸出到致動器以改變系統葉片之
勁度和阻尼特性,進而改變軸-圓盤扭轉與葉片彎曲之耦合振動行為‧
從數值結果發現系統中存在兩種耦合振動,除了葉片與轉軸的耦合振動之
外,同時亦存在葉片之間的耦合振動,且此種振動大都存在於重覆現象頻率
‧本研究最後並進行控制參數效應分析,亦即探討系統頻率對控制參數之
敏感性‧

This research employs the assumed-mode method to study the
vibration behavior of shaft-disk-blades system that contain
some active blades for vibration control.The torsional
vibration of shaft due to loads at blades is looked into as
well.
The mode shapes of a shaft-disk unit and those of a clamped-free
blade arefirst selected as the bases in the assumed-mode method.
It yields the discreteequations of motion of the shaft-disk-
blades unit that contains a couple of active blades composed
of piezo ceramics. The active blades in this research perform
as an actuatoras well as a sensor. With the PD control law, the
activeblades then reduce the vibrationlevel to some extent.
Numerical simulations reveal that there exist shaft torsion-
blade bending coupled vibration and the blades coupling
vibrations. In the blades coupling modes,the blades balance
themselves such that the resultant torque applied to the shaft
is zero. In other words, the shaft works as a rigid foundation
to the blades. These modes usually happen at repeated
frequencies of the system. At last, the sensitivities of control
parameters, i.e., PD gains, are also discussed.