Dynamic modeling of gearbox faults: A review

Design optimization of a giant magnetostrictive driving system for large stroke application considering vibration suppression in working process

In this article, a concise and practical analytical method of transmitted torque calculation for pre-design of Axial Permanent Magnetic Coupler (APMC) by combining Faraday's law with magnetic circuit model is proposed. The proposed method is able to consider the three-dimension (3D) edge magnetic effect as well as the induced magnetic field generated by eddy currents. The correctional skin depth factor is also taken into consideration. In order to verify the validity of the proposed method, the 3D finite element method (FEM) is employed. The results present that the relative error between the proposed method and 3D FEM in the normal working slip range is within 5.2%. Finally, detailed analysis is carried out to investigate the influence of the common parameters on the transmitted torque for APMC. Moreover, the deficiencies of this proposed method and the corresponding design considerations are also discussed, which offers useful and auxiliary information for the pre-design of APMCs.

A Concise Transmitted Torque Calculation Method for Pre-Design of Axial Permanent Magnetic Coupler

Reliability and optimal triggering policy for multi-state systems subject to shocks and supported by a protective device

https://iopscience.iop.org/article/10.1088/1361-665X/ab2dd0/pdf

The model of active vibration control based on giant magnetostrictive materials

An ideal positioning response is very difficult to realize in the large electric cylinder system that is applied in missile launcher because of the presence of many nonlinear factors such as load disturbance, parameter variations, lost motion, and friction. This paper presents a piecewise control strategy based on the optimized positioning principle. The combined application of position interpolation method and modified incremental PID with dead band is proposed and applied into control system. The experimental result confirms that this combined control strategy is not only simple to be applied into high accuracy real-time control system but also significantly improves dynamic response, steady accuracy, and anti-interference performance, which has very important significance to improve the smooth control of the large electric cylinder.

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Research of Control Strategy in the Large Electric Cylinder Position Servo System

Establishing the analytical model for accurately predicting the transmitted torque of the permanent magnet eddy current coupler (PMEC) with double conductor rotors is very important to study the nonlinear transmission performance of the PMEC. In this paper, based on magnetic equivalent circuit (MEC) approaches, considering the effects of permanent magnet (PM) end leakage, side leakage, and back iron saturation, the 3D magnetic field model of the PMEC is established. Based on the magnetic field model, combined with Faraday’s law and Ampere’s law, the 3D nonlinear model of the PMEC is established. The proposed model adopts the Jenei method to describe the inductance limited eddy current field. The theoretical data, 3D finite element method (FEM) data, and experimental data are compared. The research shows that the predicted value of the analytical model matches well with the torque obtained by 3D FEM and experiments in the range of 0-100% slip, with an error less than 5.3% observed. Finally, the influence of structural parameters on the transmission performance of the PMEC is studied by using the proposed model.

/pdf/nonlinear-modeling-of-transmission-performance-for-permanent-3fomfewvxw.pdf

Nonlinear Modeling of Transmission Performance for Permanent Magnet Eddy Current Coupler

The output characteristics of giant magnetostrictive actuator (GMA) are affected by many nonlinear factors, such as hysteresis, load, driving frequency and so on, which would lead to lower positioning precision, poorer repeatability, and even fall into nonlinear instability especially in complex dynamic environment. First, the accurate dynamic mathematical model for GMA is established after analyzing its working principle. Then, the inverse model feed-forward compensation fuzzy PD control based on Lyapunov stability is put forward and applied into the GMA control system. The experiment results indicate that Lyapunov direct method that is integrated into inverse model feed-forward compensation fuzzy PD controller can effectively improve the dynamic output features especially in the complex dynamic environment, reduce the root mean square error from 1.275 to 0.332 and maximum error rate from 26.89% to 7.12%, which not only greatly improve performance and expand the application domain of GMA, but also have very important theoretical significance and high application value in modeling and control approach for some hysteresis systems.

/pdf/research-on-control-strategy-in-giant-magnetostrictive-56df6u49oa.pdf

Research on Control Strategy in Giant Magnetostrictive Actuator Based on Lyapunov Stability

Active vibration control to suppress structural vibration of the flexible structure is investigated based on a new control strategy considering structure-actuator interaction. The experimental system consists of a clamped-free rectangular plate, a controller based on modal control switching, and a magnetostrictive actuator utilized for suppressing the vibrations induced by external excitation. For the flexible structure, its deformation caused by the external actuator will affect the active control effect. Thus interaction between structure and actuator is considered, and the interaction model based on magnetomechanical coupling is incorporated into the control system. Vibration reduction strategy has been performed resorting to the actuator in optimal position to suppress the specified modes using LQR (linear quadratic regulator) based on modal control switching. The experimental results demonstrate the effectiveness of the proposed methodology. Considering structure-actuator interaction (SAI) is a key procedure in controller design especially for flexible structures.

Active vibration control based on modal controller considering structure-actuator interaction

There is a serious nonlinear between the sensitive parameters and the transmission capacity of the permanent magnet eddy current magnetic coupler (PMEC), and how to establish the accurate analytical model is very important to study its characteristics, optimize design and improve control accuracy. In order to solve the problem that the accuracy of analytical model deteriorates under the variable parameters of the PMEC, based on the electromagnetic-thermal theory, the electromagnetic-thermal nonlinearity of materials, such as the thermal effect of magnetic properties, the thermal effect of permeability, the thermal effect of conductivity, the magnetic saturation effect, the skin effect, the eddy current inductive reactance, have been deeply studied in this paper. On this basis, the multi-field coupling analytical model of the PMEC sensitive parameters and material electromagnetic thermal nonlinearity is established by using the magnetic equivalent circuit theory and lumped parameter thermal network method. Combined with numerical simulation and experiment, the research on electromagnetic characteristics, temperature characteristics and transmission characteristics of the PMEC are carried out. The comparative study shows that the proposed analytical model can accurately analyze the electromagnetic characteristics, temperature characteristics and transmission characteristics of the PMEC without any correction coefficient under different parameters. The accuracy of the analytical model with variable parameters is effectively solved, and the model theory of the PMEC is improved. The accurate analytical modeling method has laid theoretical foundation for the rapid optimization design and wide application of the PMEC.

/pdf/an-improved-analytical-model-of-permanent-magnet-eddy-31t7q4timw.pdf

Yongguang Liu

Papers

Research of Control Strategy in the Large Electric Cylinder Position Servo System

Nonlinear Modeling of Transmission Performance for Permanent Magnet Eddy Current Coupler

Research on Control Strategy in Giant Magnetostrictive Actuator Based on Lyapunov Stability

Active vibration control based on modal controller considering structure-actuator interaction

An Improved Analytical Model of Permanent Magnet Eddy Current Magnetic Coupler Based on Electromagnetic-Thermal Coupling