节点文献
高速电梯水平振动主动控制研究
Active Control of Horizontal Vibrations for High-Speed Elevator
【作者】 冯永慧;
【导师】 张建武;
【作者基本信息】 上海交通大学 , 车辆工程, 2008, 博士
【摘要】 随着城市高层和超高层建筑的不断涌现,电梯的速度在不断地提高。电梯速度的提高,使得电梯的水平振动加剧,影响了乘坐舒适性以及电梯的使用寿命。高速电梯的水平振动控制成为一项重要课题。传统的减振措施包括提高导轨精度,改变电梯尺寸以及在轿架与导靴之间安装减振弹簧等,这些被动减振的方式不需外界能源,简单易行,经济性与可靠性好,在电梯速度较低时,有满意的效果。随着电梯速度的提高,被动减振的局限性显示出来,振动主动控制技术成为解决电梯振动的一条新途径。针对上述情况,本文进行了电梯水平振动主动控制的研究,首先建立了电梯水平振动的数学模型,然后完成了液压主动导靴及其控制策略的设计,对液压作动器的保压性能及控制策略进行了仿真验证和台架试验,最后对电梯轿厢位姿的鲁棒镇定控制进行了研究。进行电梯水平振动控制研究和实时仿真时需要建立电梯水平振动的动力学模型,所建模型的可靠与否将直接关系到系统响应分析与控制的有效性。基于刚体动力学理论,把电梯轿厢的运动分解为平动和绕质心的转动,根据牛顿运动定律和欧拉方程给出了电梯轿厢水平振动的动力学模型,把导轮简化为质量-弹簧-阻尼结构,在MATLAB/Simulink环境中建立了电梯水平振动的仿真模型,以实测导轨激励为输入对模型进行了仿真验证,仿真所得轿厢水平振动的加速度响应及其功率谱密度与实测结果吻合程度较高,表明所建模型是正确的,能够满足仿真精度要求及后继研究的需要。导致电梯水平振动的因素有多种,其中导轨的不平度是产生电梯水平振动的主要因素之一,对于运行速度低于5 m/s的电梯,水平振动主要来源于此。而导靴在电梯轿厢的运行过程中可以衰减由导轨不平度引起的水平振动,保证电梯的平顺行驶,提供良好的乘坐舒适性。因此,研究新型的电梯主动导靴,实现高速电梯的水平振动主动控制,具有重要的意义。按照这个思路,在被动导靴的基础上,设计了液压作动器,开发了一种新型的液压主动导靴,针对液压系统的非线性、时变等特性,分别进行了液压主动导靴的逻辑门限值控制研究和模糊控制研究,并且以导轨激励作为前馈输入变量,对模糊控制进行了预瞄补偿。利用MATLAB/Simulink的工具箱和函数库编制了仿真软件,对液压主动导靴的保压性能以及控制策略进行了仿真试验,仿真结果证明了液压主动导靴的有效性和模糊预瞄控制策略的优越性,同时说明只要保证液压作动器的保压性能,即可保证电梯水平振动在允许的范围之内,从而保证电梯的乘坐舒适性。在理论分析和仿真试验的基础上,设计了液压主动导靴的试验台架。从导轨激励模拟装置、液压系统以及单片机控制系统三个方面叙述了试验台架的结构和工作原理,利用该模拟试验台架进行了液压系统动态特性试验以及电梯水平振动主动控制模拟试验,试验中对比和优化了控制策略。试验结果证明了液压系统具有良好的响应快速性和稳定性,验证了液压装置及其控制策略的性能,试验结果与仿真结果基本一致。电梯轿厢的位姿系统具有非线性、变参数、受不确定性外扰的作用等特点。为了进一步提高电梯,尤其是超高速电梯的水平振动的控制效果,本文最后进行了电梯轿厢位姿的镇定控制律设计。结合电梯水平振动模型,首先利用微分几何的方法实现了电梯轿厢姿态系统的反馈线性化。为了消除参数不确定性及外扰作用的影响,应用Lyapunov方法分别针对轿厢的平动和转动设计了位置鲁棒控制器和姿态鲁棒控制器。其中,应用位移、速度和加速度反馈和Lyapunov方法设计了位置控制律;利用极点配置的方法和Lyapunov方法设计了姿态控制律。最后在MATLAB/Simulink环境下对鲁棒主动控制率进行了仿真验证。仿真结果证明了在系统参数发生变化及存在外部干扰的情况下,鲁棒镇定控制律能够实现电梯轿厢位姿的有效控制,使电梯的水平振动明显降低,从而为更好地实现高速电梯水平振动的减振提供了一条良好的途径。国内经济以及建筑业的迅速发展决定了国内市场对高速以及超高速电梯的大量需求;本文对高速电梯水平振动主动控制的研究,对我国电梯业的发展,尤其是高速以及超高速电梯的发展具有重要的意义。
【Abstract】 With the development of high and super-high buildings, elevator speed is now improving faster and faster, which results in serious horizontal vibrations. These vibrations can reduce the passengers’ride comfort and even the elevator’s service life. Suppression method of horizontal vibrations is therefore required for high-speed elevators. The conventional horizontal vibration reduction techniques include improving the guide rails’quality and using passive guide roller system with stiff spring. These passive suppression methods need no power supply and have the advantages of simple structure、low price and high reliability and can work well when the elevator speed is low. But they cannot do with the increasing elevator speed. Active vibration reduction techniques can flexibly cope with the new situations and have good effects and have been used widely. Accordingly, studies on the active suppression method of horizontal vibrations for high-speed elevators have been advanced.We carry on the study of active control of horizontal vibrations for high-speed elevator in this dissertation. First the mathematical model of the horizontal vibrations for elevator is given, then a new type of active guide roller system based on hydraulic actuator is designed, and the control strategy is developed to control the hydraulic actuator. Computer simulations and experimental tests are performed to verify the effectiveness of the hydraulic device and its control strategy. Last, the robust stabilized control of the position and attitude of the elevator cage is researched.Considering the real-time simulation and the convenience of the control research about the horizontal vibrations, a dynamic model about the elevator horizontal vibrations should be presented. Precision of the model would have strong effect on the effectiveness of the response analysis and the efficiency of the controller to be developed. The space dynamic model of the elevator cage is developed based on the theory of rigid body dynamics. The motion of the elevator cage is resolved into translation and rotation round the mass center of the cage. Motion equations of the cage are given according to Newton’s second law of motion and Euler equations. The guide rollers are modeled as mass-spring-damper units. Simulation model of the horizontal vibrations of elevator is developed in MATLAB/Simulink environment and simulations are executed using the measured guide rail unevenness data. Simulation results of the horizontal acceleration and the power spectral density are identified with the testing results, which verify the correctness and the accuracy of the model. This model can be used for future simulation analysis and the control research. There are many reasons contributing to the horizontal vibrations of elevators. These horizontal vibrations are mainly generated by the irregularity of the guide rails, especially for the elevators traveling at the velocity below 5 m/s. As the three rollers of the guide system can weaken the horizontal vibrations from the irregularity of the guide rails and provide good ride comfort, developing a new type of active guide roller system with good ability of vibration isolation is very important. So a new type of active guide roller system based on hydraulic actuator is proposed in this dissertation. First the structure and the working principle of the hydraulic active guide roller system are analyzed. The mathematical model of the system is given. Then the logical thresh-hold controller and the fuzzy logic controller with preview compensation are designed, respectively. Simulation software is developed utilizing the toolbox and the function of MATLAB/Simulink. Computer simulations are performed to verify the effectiveness of the hydraulic device and the superiority of the fuzzy logic controller with preview compensation. Simulation results also give the conclusion that as long as the the oil pressure of the hydraulic cylinder be kept the objective value with permitted error range, the horizontal vibrations of the elevator would be kept within the permitted range and ensure the passengers’ride comfort.Then test rig is designed based on the working principle of the hydraulic active guide roller system and the simulation results. The test rig is made up of a guide rail simulator, a hydraulic station and a single-chip-microcomputer based control system. Hydraulic dynamic characteristic examination and the active control experiments are executed using the test rig. Optimization and comparison of different control methods are also given. Experimental results show that the hydraulic system can respond rapidly and stably, and can confine the oil pressure in the permitted range. Of all the control methods, the fuzzy logic controller with preview compensation has the best performance. The experimental results are consistent with simulation results.Taking account of the characteristics of nonlinearity、parameter uncertainties and external disturbances of the elevator cage, the position and attitude stabilization of the elevator cage is performed so that the horizontal vibrations of elevator can be attenuated more effectively in any case. Input/output feedback linearization approach is used to realize the linearization of the attitude model first, and robust controller is designed using Lyapunov method. To simplify the controller design, the position controller and the attitude controller are designed based on the translation model and the rotation model, respectively. Placement、velocity and acceleration feedback and the Lyapunov method are used to design the position controller, pole placement and Lyapunov method are used to design the attitude controller. Simulation is performed in MATLAB/Simulink environment. The results demonstrate the effectiveness of the proposed controller, the position and attitude of the elevator cage are stabled successfully and the horizontal vibrations of the elevator can be reduced effectively in the presence of the parameter uncertainties and the external disturbances. This work supplies an efficient way to future research for better effect of horizontal vibrations control.The rapidly developing economy and architecture industries decide the great requirements of high-speed and super high-speed elevators in domestic market. The study on active control of horizontal vibrations for high-speed elevator in this dissertation could provide a helpful reference for the development of high-speed and super high-speed elevator and is very important for local elevator industries.
【Key words】 High-speed elevator; Horizontal vibration; Active control; Hydraulic active guide roller system; Rig test; Position and attitude control;