磁流变阻尼器多目标靶向抑制四跨转子轴系过临界转速振动实验研究

针对四跨转子轴系过临界转速易发生振动过大且各跨转子之间耦合振动复杂的问题，研究了基于磁流变阻尼器的多目标靶向在线振动控制方法。搭建四跨转子轴系实验台，设计新型磁流变阻尼器并应用于自主开发的多目标靶向在线控制系统。模拟试车过程，研究了通入磁流变阻尼器内不同大小电流时，四跨转子轴系各跨转子振动的变化情况；由于四跨转子轴系过临界转速时耦合振动剧烈，因此提出基于转速的多目标靶向在线控制方法，采用在轴系中各跨转子临界转速附近开启、非临界转速关闭阻尼器的靶向分段控制策略，来实现在线抑制转子轴系过各阶临界转速时的振动。结果表明：磁流变阻尼器能抑制各跨转子过临界转速时的振动，且电流较大时抑振效果较好；应用带有多目标靶向在线控制系统的磁流变阻尼器能使四跨转子轴系在全转速范围振动较小，运行平稳。

Experimental study of over-critical speed vibration multi-objective control of four-span rotors by means of a magnetorheological damper

In view of the problem whereby four-span rotors vibrate excessively at the critical speed, a new type of magnetorheological (MR) damper has been designed and employed as a four-span rotor vibration control system. Its effect on the vibration of the rotors was studied in this work. Four-span rotor benches were built and MR dampers were installed on each span rotor corresponding to the original support mode. Experiments were carried out to verify the effect of vibration suppression with different currents in the damper. The results showed that the vibration of each span rotor at the critical speed can be suppressed effectively by the MR dampers, and the suppression increased with increasing current. Since the vibration of four-span rotors is usually too large around the critical speed, this causes the adjacent rotors to vibrate. A new multi-objective control method, in which the state of the damper was switched according to the speed, was constructed: at the critical speed the damper was turned on, and at lower speeds it was turned off. In this way, the vibration of the four-span rotors can be suppressed online. The results showed that the vibration of the four-span rotors was suppressed to an even greater extent by employing the dampers together with with multi-objective control system.