| Nowadays,with the increasing number and height of high-rise buildings,the popularization of high-speed elevators has become an inevitable trend.However,the increasing speed of elevators makes the problem of horizontal vibration more and more obvious.Strong horizontal vibration will cause physiological and psychological discomfort reactions such as vertigo and vomiting to passengers,which will reduce the ride comfort of the elevator.Meanwhile,severe horizontal vibration will also affect the service life of precision parts inside the elevator,which will reduce the ride safety of the elevator.Although the traditional passive vibration damping can better reduce the vibration of low-speed elevators,it is less effective in suppressing horizontal vibration of high-speed elevator car systems,because it only adapts to external interference with little frequency change.Therefore,establishing a horizontal vibration model of a high-speed elevator which is more in line with the real service environment to explore the active control method of the horizontal vibration of the high-speed elevator car system under different influencing factors,which has important theoretical and practical significance for improving the operation quality of high-speed elevator in China.Considering the 4m/s high-speed elevator(Shandong FUJIZY Elevator Co.,Ltd.)car and car frame do not coincide with each other and the elastic connection between the car body and the car frame,the Lagrange energy method was used to establish the high-speed elevator car body and car frame Separated 8-DOF horizontal vibration model.Then,in MATLAB,the horizontal vibration acceleration of the model is simulated and analyzed.Subsequently,the horizontal vibration acceleration of the 4m/s high-speed elevator car system was measured by using the DT-4A elevator acceleration detector.Finally,the typical digital characteristics(root mean square value,mean value,maximum value)of the horizontal vibration acceleration of the simulated car system and the measured car system are solved and analyzed in the time domain,and the trend of the simulation curve and the measured curve are compared and analyzed in the frequency domain.The results show that in the time domain,the relative error between the typical digital characteristics of the simulated horizontal vibration acceleration of the car and the typical digital characteristics of the measured value is 2.05%,4.63%,4.44%,and the relative error between the typical digital characteristics of the simulated horizontal vibration acceleration of the car frame and the typical digital characteristics of the measured value is 4.62%,7.12%,1.54%.In the frequency domain,both measured and simulated values show that the maximum amplitude of the horizontal vibration of the car system is concentrated in the low frequency range of 0-5 Hz,and the vibration trend is basically the same.Therefore,the established model is more accurate,which lays a foundation for the subsequent study on the active control method to suppress horizontal vibration of the car system.In view of the disadvantages of the existing hydraulic guide shoe,such as slow actuation speed,no buffering of the oil,and the time lag characteristic of the control system,based on the theory of hydraulic and pneumatic transmission,the gas-liquid active guide shoes are designed by using the components such as gas-liquid converter and gas-liquid cylinder.Further,introduced it into the established high-speed elevator horizontal vibration model,and a highspeed elevator horizontal vibration active control model is established.According to the theory of robust control,the horizontal vibration acceleration output of the car system is described by the H2 norm,and based on the linear matrix inequality(LMI)optimization technology,an H2 optimal robust controller is designed to minimize the horizontal vibration acceleration of the output car system.Finally,in MATLAB,the high-speed elevators under different load operating conditions(no load,medium load and full load)are simulated and analyzed.The results show that under no-load,medium-load and full-load operating conditions,compared with no control,the typical digital characteristics of the horizontal vibration acceleration of the high-speed elevator car system are all reduced by more than 14%,and the typical digital characteristics of the horizontal vibration displacement(mean value,maximum value)of the car system are all reduced by more than 13%.Therefore,the robust controller can effectively reduce the horizontal vibration of the car system and has a certain robustness to the change of load,which provides a theoretical basis for the design of the controller used to actively suppress the horizontal vibration of high-speed elevators in engineering practice.Considering the mechanical stroke constraint and power constraint of the guide shoe actuator in the operation of high-speed elevator,according to the design principle of automobile active suspension,the calculation formulas of the mechanical stroke and power of the gas-liquid active guide shoes actuator are derived.Based on the designed optimal robust controller,the constraint problems of the gas-liquid active guide shoes are described by the generalized H2 norm.Based on LMI optimization technology,an H2/generalized H2 hybrid control strategy is proposed,which summarizes the control law of the car system to solve the semi-definite programming problem with LMI constraints.Finally,the optimal state feedback gain is solved in MATLAB,and the vibration acceleration of the high-speed elevator under different load operating conditions is simulated and analyzed.The results show that the typical digital characteristics of the horizontal vibration acceleration of the car are reduced by more than 24% after the H2 / generalized H2 control method is adopted,and the vibration reduction effect is better than that of the traditional PID control.Therefore,the control method proposed can significantly reduce the horizontal vibration of high-speed elevator,and provide a theoretical basis for the application of active vibration reduction in engineering practice.In view of the non-linearity of the gas-liquid guide shoe actuator and the existing active control algorithm,which has no specific reasoning basis and self-learning ability for the vibration reduction of the car system,a high-speed elevator fuzzy neural network intelligent vibration damping controller based on the Mamdani model is designed according to the intelligent control theory.In MATLAB,the horizontal vibration acceleration of high-speed elevator car system under no-load,mid-load and full load conditions is simulated in the time domain and frequency domain.The results show that in the time domain,after adopting the fuzzy network control method,the typical digital characteristics of the horizontal vibration acceleration of the car system are reduced by more than 55%,and the vibration reduction effect is better than the BP neural network control.In the frequency domain,the effect of suppressing low-frequency vibration of high-speed elevators is better.Therefore,the designed intelligent vibration damping controller can effectively reduce the horizontal vibration of high-speed elevators,which provides new ideas and methods for the study of the active vibration control method of high-speed elevator car systems considering nonlinear problems. |
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