Vibration Analysis and Control of Nuclear Power Crane with MRFD

2018 ◽  
Vol 10 (08) ◽  
pp. 1850093 ◽  
Author(s):  
Yi Xiao Qin ◽  
Bo Lun Li ◽  
Xin Li ◽  
Yan Qing Li ◽  
Zhi De Zhang ◽  
...  

The nuclear power crane is required to have high security and stability, as its lifting mechanism and span structure are needed to perform predominantly in serious working conditions. A new vibration analysis and control method on the nuclear power crane is proposed to improve its stability, which is based on magneto rheological fluid damper (MRFD) and switch algorithm control strategy. The simulation is completed through dynamic model and control model. The experiment is accomplished in a serving crane. Both numerical simulated and experimental results show that the vibration of nuclear power crane is suppressed significantly with MRFD. It is proved that MRFD should be taken into consideration in the vibration control of nuclear power crane.

Electronics ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 1058 ◽  
Author(s):  
Chuanxiang Ren ◽  
Jinbo Wang ◽  
Lingqiao Qin ◽  
Shen Li ◽  
Yang Cheng

Setting up an exclusive left-turn lane and corresponding signal phase for intersection traffic safety and efficiency will decrease the capacity of the intersection when there are less or no left-turn movements. This is especially true during rush hours because of the ineffective use of left-turn lane space and signal phase duration. With the advantages of vehicle-to-infrastructure (V2I) communication, a novel intersection signal control model is proposed which sets up variable lane direction arrow marking and turns the left-turn lane into a controllable shared lane for left-turn and through movements. The new intersection signal control model and its control strategy are presented and simulated using field data. After comparison with two other intersection control models and control strategies, the new model is validated to improve the intersection capacity in rush hours. Besides, variable lane lines and the corresponding control method are designed and combined with the left-turn waiting area to overcome the shortcomings of the proposed intersection signal control model and control strategy.


Author(s):  
Jianxiao Wang ◽  
Guang Meng ◽  
Eric Hahn

A squeeze mode MR fluid damper used for rotor vibration control is designed and manufactured, and the unbalance response properties and control method of a single-disk flexible rotor system supported by the damper are studied experimentally. It is found from the study that the magnetic pull force can decrease both the first critical speed and the critical amplitude; the oil film reaction force can decrease the amplitude at the undamped critical speeds, but increase the amplitude in a speed range between two undamped critical speeds. For the rotor system supported by a journal bearing and an MR fluid damper, it is possible to appear oil film instability as the increasing of the control current. The damper may have the best effect to make the vibration minimize within the range of all working speed by using on-off control method. The research show that the squeeze mode MR fluid damper has the advantages such as simple structure, clearly effectiveness, quick response, etc., and this kind of damper has a promising potential future in vibration control of flexible rotor systems.


2020 ◽  
Vol 25 (3) ◽  
pp. 363-372
Author(s):  
Vanliem Nguyen ◽  
Zhenpeng Wu ◽  
Beiping Zhang ◽  
Zhang Jian Run

To reduce shaking of a vibration screed system (VSS) and improve the paving performance of an asphalt paver (AP), the root-mean-square (RMS) acceleration responses at points on the front and rear screed floors are analyzed via an experimental method. A 3D nonlinear dynamic model of the VSS is also built to evaluate the influence of the dynamic parameters of the VSS on the compression efficiency, paving quality, and working stability of the AP based on the objective functions of the vertical, pitching, and rolling RMS values at the centre of gravity of the screed. The angular deviations, $alpha$ and $gamma$, of the tamper are then controlled to improve the paving performance. The research results show that the excitation frequency, $f_{t}$, and both angular deviations, $alpha$ and $gamma$, of the tamper strongly affect the paving performance. The compression efficiency is quickly enhanced, while both paving quality and working stability are significantly reduced with increasing the excitation frequency $f_{t}$ and reducing the angular deviations. $alpha$ and $gamma$. and vice versa. Additionally, the screed shaking and paving performance of the AP are remarkably improved by control of the angular deviations, $alpha$ and $gamma$, under different working conditions.


2020 ◽  
Vol 10 (20) ◽  
pp. 7021
Author(s):  
Yan Li ◽  
Peng Xiang ◽  
Yandong Chen

This article proposes a topology of the secondary reconfigurable inverter and the corresponding fault-tolerant control strategy. When the secondary reconfigurable inverter is operating normally, its topology structure is the TPSS circuit. When the power semiconductor devices in the inverter are faulty, the inverter circuit needs to be reconfigured. After removing the faulty power semiconductor devices, the remaining power semiconductor devices and the DC side powers are reconstructed as the TPFS structure to keep the system running normally. This article also proposes a switch-pulse-resetting algorithm. This paper adopts the control strategy connecting the constant-voltage, constant-frequency control method with the switch pulse resetting algorithm. It need not change the control algorithm when the proposed reconfigurable inverter is transformed from the normal running state into the faulty running state. The inverter dependability is greatly improved. Finally, the feasibility and effectiveness of the proposed second reconfigurable inverter topology and control strategy are verified by simulation and experiment.


Author(s):  
Xiaoqing Zhang ◽  
Weijing Zhang ◽  
Jun Chen

A “bird” is a device usually being used to control the depth and position of marine seismic streamers. Exact position of the streamers can effectively promote the precision, reduce the measured times and save the costs for marine seismic exploitation. So the “birds” have important significance to marine oil exploitation. A Hydrodynamic characters test concerning a new embedded bird has been introduced in this paper. And some useful hydrodynamic character-data of the hydrofoil are obtained, such as lift-attack angle diagram, resistance-attack angle diagram, torque-attack angle diagram. These data and diagrams are more helpful for studying on the embedded bird, including the control method and control strategy etc. Above all, the results of the test have significant reference value for the control of birds and marine seismic streamers.


2013 ◽  
Vol 787 ◽  
pp. 886-890
Author(s):  
Lan Chun Zhang ◽  
You Jun Ma ◽  
Shao Yi Bel

In this paper,a novel CVT with electronic control and a motor as actuator (EM-CVT) is presented, whose speed ratio can be adjusted by driving the two movable discs of the primary and secondary pulley at the same time. Firstly, the EM-CVT transmission dynamics mode was established based on the analysis of EM-CVT working principle and ratio change characteristics. Secondly, the speed ratio control strategy and control method for EM-CVT was designed according to the EM-CVT features and functional requirements of the control system; Finally, the simulation was carried out to verify the validity of the control strategy and meth


2013 ◽  
Vol 401-403 ◽  
pp. 1822-1825
Author(s):  
De Qi Ren

Aimed at the puzzle that it is heavy in energy consumption and not better in water quality to water supply engineering resulted in inappropriate control strategy, the paper explored the energy saving strategy and control mechanism of water supply system. In the paper, it discussed the cybernetics characteristic of water supply process, proposed the intelligence-fusion based control strategy and the energy saving executing strategy, and analyzed the control model of water supply purifying process and the control algorithm of constant pressure control system. The comparative research of simulation demonstrated that the proposed strategy would be better than conventional PID control method. The simulation results show that the strategy combined intelligence-fusion based control with speed control by inverter has better application prospect.


Sign in / Sign up

Export Citation Format

Share Document