Study on electromechanical coupling torsional resonance characteristics of gear system driven by PMSM: a case on shearer semi-direct drive cutting transmission system

Considering the microstructure of tooth surface and the dynamic characteristics of the vibration responses, a compound dynamic backlash model is employed for the gear transmission system. Based on the fractal theory and dynamic center distance, respectively, the dynamic backlash is presented, and the potential energy method is applied to compute the time-varying meshing stiffness, including the healthy gear system and the crack fault gear system. Then, a 16-DOF coupled lateral-torsional gear-rotor-bearing transmission system with the crack fault is established. The fault characteristics in the time-domain waveform and frequency response and statistics data are described. The effect of crack on the time-varying meshing stiffness is analyzed. The vibration response of three backlash models is compared. The dynamic response of the system is explored with the increase in crack depth in detail. The results show that the fault features of countershaft are more obvious. Obvious fluctuations are presented in the time-domain waveform, and sidebands can be found in the frequency domain responses when the tooth root crack appears. The effect of compound dynamic backlash on the system is more obvious than fixed backlash and backlash with changing center distance. The vibration displacement along meshing direction and dynamic meshing force increases with the increase in crack depth. Backlash and variation of center distance show different tendencies with increasing crack depth under different rotational speeds. Amplitude of the sidebands increases with crack depth increasing. The amplitude of multiplication frequency of rotational frequency has an obvious variation with growing crack depth. The sidebands of the multiplication frequency of meshing frequency show more details on the system with complex backlash and crack fault.

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Research on operating domain optimization of power split hybrid electric vehicle based on global bifurcation and chaos threshold

Advances in Mechanical Engineering ◽

10.1177/1687814020954608 ◽

2020 ◽

Vol 12 (9) ◽

pp. 168781402095460

Author(s):

Dou Lei ◽

Cai Yingfeng ◽

Chen Long ◽

Shi Dehua ◽

Hu Donghai ◽

...

Keyword(s):

Electric Vehicle ◽

Hybrid Electric Vehicle ◽

Electromechanical Coupling ◽

Transmission System ◽

Optimization Scheme ◽

Domain Optimization ◽

Driving Mode ◽

Power Split ◽

Non Linear ◽

Hybrid Electric

The power-split hybrid electric vehicle (PS-HEV) has multiple working modes to maintain high operation efficiency according to different conditions. The main modes involved in the vehicle driving process are pure electric mode and the hybrid driving mode. Because the electromechanical coupling problem is involved in the above two working modes, the transmission system exhibits strong non-linear characteristics. If the operation range of the engine and motor are unreasonable, the rotor system will vibrate and become instability. In this paper, the non-linear dynamic equations of the electromechanical coupling of the transmission system are established for electric driving mode and hybrid driving mode. The closed-homoclinic phase trajectory equation at the center point of the disturbance-free Hamilton system is determined. The chaotic thresholds for the pure electric and hybrid driving modes are derived through the Melnikov’s method to obtain the optimal working domain of the engine and motor. Finally, numerical simulation analysis is conducted to verify the feasibility of the work domain optimization scheme. Simulation results show that the proposed engine and motor working area optimization scheme can effectively avoid the homoclinic bifurcation in the PS-HEV during the driving process and prevent the vehicle from entering the chaotic state.

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Integrated Design of Airborne Radar Servo System Based on MATLAB/SIMULINK

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.204-210.17 ◽

2011 ◽

Vol 204-210 ◽

pp. 17-20

Author(s):

Ding Zhen Li ◽

Rui Min Jin

Keyword(s):

Optimization Model ◽

Electromechanical Coupling ◽

Integrated Design ◽

Control Design ◽

Servo System ◽

Coupling Model ◽

Transmission System ◽

Airborne Radar ◽

Matlab Simulink ◽

And Control

This thesis is according to the pitching part of airborne radar servo system. The electromechanical coupling model and optimization model which includes structure parameters and control parameters are built up based on model of mechanism transmission system and electricity control system. The dynamics model of mechanism transmission system includes the nonlinearity of backlash and is considered the influence of parameters for dynamics properties in structure of the mechanism transmission system. The method of integrated structure and control design is applied on the optimization model using GA. Simulation is done based on MATLAB/SIMULINK. Simulation results show that the method of integrated structure and control design is feasible and effective in servo system.

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A novel direct-drive ocean wave energy extraction concept with contact-less force transmission system

Renewable Energy ◽

10.1016/j.renene.2007.01.008 ◽

2008 ◽

Vol 33 (3) ◽

pp. 520-529 ◽

Cited By ~ 31

Author(s):

Emmanuel B. Agamloh ◽

Alan K. Wallace ◽

Annette von Jouanne

Keyword(s):

Wave Energy ◽

Transmission System ◽

Ocean Wave ◽

Energy Extraction ◽

Direct Drive ◽

Force Transmission ◽

Ocean Wave Energy

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Design and Analysis of the Transmission System in Geared Turbofan Engine

Volume 2: Processes; Materials ◽

10.1115/msec2019-3062 ◽

2019 ◽

Author(s):

Yanzhong Wang ◽

Kai Yang ◽

Wen Tang

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Comparative Analysis ◽

Finite Element Method Simulation ◽

Transmission System ◽

Contact Analysis ◽

Gear System ◽

Tooth Surface ◽

Stress And Strain ◽

Element Method

Abstract A comparative analysis of the structural form and gear type of the gear-driven fan engine reducer is made. Comparative analysis of different transmission structure forms and different gear types, the results show that the star-shaped structure with herringbone gear is more suitable for aero-engine fan reducer, especially in the case of high output speed and high gear bearing capacity. According to the design conditions, the basic parameters of the gear system of the transmission system were preliminarily designed. The gear loading calculations were carried out by finite element method and ISO method respectively, and the root bending stress and tooth surface contact stress obtained by the two methods were compared and analyzed. The results show that the parameters of the fan reducer gear system designed using ISO standards are more conservative. The gear stress obtained by the finite element method simulation is close to the nominal stress calculated in the ISO standard, which verifies the rationality of the finite element model. On this basis, the gear shaping parameters are designed according to the stress and strain conditions of the finite element loading contact analysis, and the appropriate shaping parameters are obtained. Based on the stress and strain results of the finite element loading contact analysis, we designed the gear modification parameters and obtained the appropriate modification parameters.

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Nonlinear Torsional Vibration Analysis and Control of Semidirect Electromechanical Coupling Transmission System in Shearer

Shock and Vibration ◽

10.1155/2019/7431239 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12

Author(s):

Song Jiang ◽

Wei Li ◽

Lianchao Sheng ◽

Jiajun Chen ◽

Min Li

Keyword(s):

Hopf Bifurcation ◽

Torsional Vibration ◽

Electromechanical Coupling ◽

High Reliability ◽

Permanent Magnet Synchronous Motor ◽

Nonlinear Damping ◽

Transmission System ◽

Concentrated Mass ◽

Mass Model ◽

Hurwitz Stability

The nonlinear torsional vibration and instability oscillation caused by nonlinear damping in the shearer electromechanical coupling cutting transmission system in shearer driven by the permanent magnet synchronous motor (PMSM) is investigated in this paper. The electromechanical coupling transmission system in the shearer is equivalent to a concentrated mass model for the purpose of establishing the system dynamic model by the Lagrange–Maxwell equation. Then, the Routh–Hurwitz criterion is used to determine the torsional vibration critical point and stability region for the Hopf bifurcation for the cutting transmission system. According to the Routh–Hurwitz stability criterion, the Hopf bifurcation type and the effect of the supercritical Hopf bifurcation in the torsional vibration of the cutting transmission system are analyzed. Furthermore, based on the washout filter, the Hopf bifurcation controller is designed for suppressing the transmission system’s large vibration amplitude and unstable oscillation. In addition, the influences of the linear gain and nonlinear gain on the bifurcation point and the limit cycle amplitude are discussed. Finally, the numerical simulation results indicate the effectiveness of the designed controller. The research achievements can provide a theoretical basis for design or optimize the cutting transmission system of high-reliability shearer driven by PMSM.

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