| As an important lifting method of mining transportation,friction lifting system has been widely used in deep lifting widely because of its significant advantages such as lifting load and lifting depth.With the increase of lifting depth and load,due to the roller rotation error and wear,the tensions of parallel lifting ropes are uneven,the resonance of conveyance is large,and the compensating rope swing is too large,which will not only increase the risk of rope’s broken,but also cause strong reciprocating vibration of conveyance,swing and collision of the compnesating rope,and even kink twining.It seriously affects system’s safety and reliability.Therefore,it is of great significance to research about the tension difference of parallel lifting rope,conveyance vibration and large swing of compensating rope.In this research,the time-varying length distribution mass friction lifting system under multiple constraints is taken as the working condition.In view of the characteristics of the tension difference variation,vibration and resonance characteristics of conveyances and large swing characteristics of compensating rope are studied.The dynamic characteristics are given.Combined with multiple vibration control methods,Hamilton’s principle and Lagrange equation of the first kind are used for modeling.Multiscale method and finite difference method are used to solve the problem.Combined with software simulation,experimental verification and industrial application,the purpose is to master the dynamic characteristics under multiple time-varying parameter changes and put forward dynamic control strategy.It provides theoretical guidance and technical support for the efficient,safe and reliable operation of friction lifting system with large depth and load.Firstly,the coupling relationship between the torsional force and the internal friction force of the tension balancing device was considered,and coupling dynamics model of the distributed mass time-varying length parallel lifting system was established considering the friction factors of the tension balancing device and multiple constraints.The generalized α is used to solve the model.The correctness of the coupling model was verified based on AMESIM and FEM.The mechanism and changing laws are expounded,and the improvement scheme to eliminate tension difference is given.The equivalent analytical mechanics model of "error rate of drum diameter-lifting height-limit working stroke of slider in tension balancing device" was established.The limited condition and variation rule of normal operation of the slider of the tension balancing device are given,which provides theoretical support and improvement for the design of tension balance device.Secondly,the governing equations and boundary conditions of the system were derived according to the continuum theory and Hamilton’s principle.The model dynamics equation was simplified by the single-mode approximation method based on multi-scale transformation.The correctness of the established model was verified by ADAMS and experiments.The vibration resonance characteristics of the system under different lifting parameters are discussed.To eliminate container resonance,an active control scheme was proposed.Based on the universal approximation principle of the fuzzy system,disturbance observer and Lyapunov function,a fuzzy adaptive back-stepping controller was designed to control the longitudinal vibration of conveyances of the variable length lifting system.The effectiveness and adaptability of the controller were verified by simulation analysis.Thirdly,considering the large deformation,large swing of high-speed compensating rope,the theoretical model and experimental model are constructed,and the change rules are analyzed and verified by image processing and other non-contact measurement experimental means.Aiming at the problem swing,an adaptive swing suppression mechanism is constructed,and the dynamic model of traction system with adaptive tensioning rope swing suppression mechanism is established.The effect of tension pulley on swing suppression is verified by theoretical and experimental means,and the longitudinal vibration characteristics under different parameters are obtained.Finally,based on the proposed compensating rope swing suppression scheme of adding an adaptive tensioning pulley to the compensating rope,the running state and dynamic response of the swing suppression mechanism under the limited condition are analyzed,and the non-smooth dynamic model under the action of swing suppression mechanism is constructed,and the non-smooth dynamic model of the system and the dynamic response under the emergency braking are analyzed.The response of the tension system under different working conditions and the variation of the tension of the terminal pulley under different working conditions are obtained.The change law of tension response provides a theoretical basis for the safety emergency braking design of swing suppression mechanism.This thesis has 147 figures,8 tables,156 references. |
