Study The Method Of Rotor Periodic Vibration On Active Suppression Based On Electromagnetic Force

Vibration inevitably exist in the operation of rotating machinery.There are various types of excitation sources in rotating machinery,such as,imbalance,manufacturing errors due to installation,and secondary rubbing failure caused by the above vibration.Once the vibration intensifies,slight vibration will affect the quality of the production,and severe vibration will cause a shutdown accident.Aiming at the problem of active vibration suppression of rotating machinery rotor,the active vibration suppression method of rotating machinery rotor is studied by using electromagnetic actuator in this paper.The model of rotor-bearing-electromagnetic actuator system is established,and four control algorithms are proposed to realize the active suppression of rotor vibration.(1)Variable gain periodic time-delay iterative control:Based on the periodic regularity of rotor vibration,an algorithm of variable gain periodic time-delay iterative control is designed in this paper.The algorithm is independent of system model and reduces the debugging workload of controller design.The simulation proves that the algorithm effectively suppresses unbalanced vibration and unbalanced-misaligned coupling vibration.(2)Improved algorithm based on model reference adaptive control:This algorithm improves the model reference adaptive control to a certain extent.Based on considering feed-forward feedback,the unbalance compensation term is added,and the control forces at the corresponding time of the adjacent period are superimposed.In addition,in order to prevent the vibration attenuation of the rotor to a certain extent,the dead-time control is introduced in this algorithm.The simulation results show that the unbalanced vibration of the rotor is effectively suppressed by the improved algorithm.Compared with the PD control algorithm,this algorithm does not need to repeatedly debug and select parameters.(3)Mixed sensitivity H? robust control:Aiming at the nonlinear link and dynamic uncertainty existing in the rotor bearing system and the electromagnetic actuator,the H? controller is designed based on the transfer function object of the single-degree-of-freedom electromagnetic actuator.The simulation results show that the controller can not only effectively suppress the unbalanced vibration,but also have a certain suppression effect on the nonlinear unbalance-impact coupling vibration.(4)Classical PD control:The principle of classical PD control algorithm is simple and easy to implement,but no matter what kind of control object is used,there is always a problem of parameter selection.In this paper,according to the stiffness characteristics of the rotor system and the mechanical characteristics of the electromagnetic actuator,the preliminary principle of selecting proportional parameters is determined.The method of combining simulation with experiment is used to verify that the PD control can effectively suppress the unbalanced vibration of the rotor at multi-speed.