A hybrid model for Hydro-Viscous Drive(HVD) by combining a mechanism-based torque balance equation for clutch engagement and a Particle Swarm Optimization-Long Short-Term Memory(PSO-LSTM) neural ...network model is proposed to simulate the abrupt torque change accurately. The model accounts for sudden torque fluctuations under impact conditions, enhancing the accuracy of predicting the time and torque of the mutation node using data from a comprehensive test bench. The experimental validation demonstrates that the hybrid model outperforms the traditional mechanism model, reducing the average error by 20.04%. Systematic assessment highlights the stability and robustness of the model performance, showing substantial improvements over conventional neural networks. The parametric study reveals the crucial influence of rotational speed and oil temperature on torque characteristics.
•Establish torque model with mechanism and data hybrid-driven under impact condition.•Torque mutation node coordinates obtained by PSO-LSTM neural network.•20.04% improvement in accuracy compared to mechanistic modeling.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper designs and compares two outer-rotor flux switching permanent-magnet (FSPM) motors, in which the two different PM topologies of the V-shape magnet and I-shape magnet are adopted ...respectively in their stator structures, namely, V-FSPM motor and I-FSPM motor. First, the design principles and motor topologies are introduced. Second, by using the comprehensive sensitivity method and sequential nonlinear programming algorithm, the two motors are optimized efficiently before comparison, where the torque and torque ripple are selected as the design objectives. And then based on the finite element analysis (FEA) method, the motor performances are evaluated in detail, such as back EMF, torque characteristics, and efficiency. To extensively explore the advantages of the two motors, the comparison work involving output torque, torque ripple, and PM usage efficiencies are further implemented under three different conditions. Finally, the two prototyped motors are manufactured and tested, respectively. The theoretical analysis is verified by the FEA results and experimental results, which reveals that both of the two motors can be interesting and potential candidates for the in-wheel traction applications.
We propose a hybrid model that integrates conventional mechanism methods with state-of-the-art data-driven techniques to study torque characteristics during the high power clutch engagement process. ...Experimental validations using clutch bench tests demonstrate that our hybrid model has an error of 7.0%, outperforming conventional mechanistic models and reducing the average error in predicting clutch torque by 12%. With this developed hybrid model, we systematically investigated the impact of oil pressure, oil temperature, and disc size on torque characteristics under various working conditions. Our findings reveal that pressure has the most significant impact on clutch torque. While the influence of the other two factors on overall clutch torque is relatively diminished, temperature can significantly change the viscous torque and disc size can markedly change torque generation time.
•Establish wet friction pairs torque model with mechanism and data hybrid-driven.•The data model provides real-time friction coefficients for the mechanistic model.•Model error is 7.0%, compared with the mechanism model, the error decreases by 12%.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The purpose of this study is to determine the influencing factors and changing laws of the friction behavior of a wet clutch under actual working conditions. A qualitative analysis is conducted on ...the torque characteristics of a wet clutch and influence laws such as the relative and absolute speeds of the driving and driven ends of the clutch, lubricant flow, engagement force and its change rate, lubricant temperature, and friction surface temperature. The identified influence mechanisms and friction behavior can be used for the design and production of a precise controller for the transmission torque of a wet clutch.
•Analysis of a wet clutch was performed under actual working conditions.•Precise design of controller was explored for transmission torque of wet clutch.•Influencing factors and changing laws of friction behavior were explored.•Relative and absolute speeds of driving and driven ends of a clutch were determined.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This article presents a new design of a multi-pole magnetorheological (MR) clutch, with a hybrid magnetization using several permanent magnets and several excitation coils. The permanent magnets are ...used as the first source of generating the magnetic field, and the excitation coils are used to adjust the magnetic field to the required value. Firstly, a detailed illustration of the mechanical design of the MR clutch is presented. The principal design parameters of the proposed clutch are determined to achieve maximum torque according to the magnetic circuit. After that, the torque model is established, and simulations are conducted to evaluate the magnetic circuit design. Subsequently, an experimental set-up is established, and the proposed MR clutch is designed and manufactured, and a series of experiments are carried out. The results clearly show that different torque output can be obtained by controlling the current magnitude and direction of each coil. Finally, to achieve a precise feedback torque control, the design of a current controller is carried out using conventional proportional-integral-derivative (PID) control scheme. The results demonstrate that the designed PID controller can be used to obtain the desired torque.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
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•A novel mechatronics-electro-hydraulic power coupling system is proposed.•An electro-hydraulic ratio distribution method is proposed targeted on the electric torque.•Different ...distribution ratios are discussed for torque and energy-saving characteristics.•The optimal ratios are determined with battery state of charge as the constraint.•The practical engineering application potentials are verified on actual driving conditions.
The engagement and distribution ratio of electric and hydraulic power will certainly affect the stability and efficiency of the mechatronic-electro-hydraulic power coupling (MEHPC) system. This paper proposes a novel MEHPC electric vehicle, which integrates the traditional motor with the hydraulic pump/motor to realize the mutual conversion of electrical energy, mechanical energy, and hydraulic energy. A distribution method for the electro-hydraulic ratio under different working modes is proposed taking the electric peak torque as the optimal target. Compared with the AMESim certified cycle, the results indicate that the MEHPC system can significantly reduce electric peak torque and improve the battery's state of charge (SOC) after the proportional distribution. Simultaneously, the article determines the optimal ratio by multiple optimization objectives with SOC as the constraint. The results illustrate that the phenomenon of torque surge can be reduced under the appropriate proportion, and the battery energy consumption rate is reduced by 33.54% compared to pure electric vehicles. Moreover, the actual driving conditions are analyzed utilizing actual data acquisition and simulation. The results suggest that the peak torque is lower than pure electric vehicles, and the energy utilization is improved substantially with the battery consumption reduced by 20.86%. Therefore, the proposed method combines better energy efficiency, stability, and economic performance, which will be expected to provide a good reference for the development of electro-hydraulic systems.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK, ZAGLJ, ZRSKP
A kinematic coupling model of the rotation-axial engagement process of friction elements is established based on the oil film dynamic pressure lubrication and an elastic contact model of the ...asperities. The engagement characteristics of the multi-disc wet friction clutch are analyzed. The equation for the transmission torque of the clutch is derived by considering the axial movement of the friction elements and the surface morphology of the friction pairs. The influences of the piston pressure and the number of friction pairs on the speed and transmission torque of the clutch during engagement are analyzed considering the viscous torque and the contact torque. Finally, the effects of engagement pressure on the torque and engagement time of the clutch are verified.
•The coupling model of the rotation-axial engagement process of friction elements is established.•The ultimate shear stress of the lubricating oil is taken into account.•The shaft torsion stiffness and split spring between steel disc is taken into consideration.•The effect of the friction pairs number on clutch speed, torque and film thickness is analyzed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The doubly salient electromagnetic machine (DSEM) is a suitable candidate in many industrial applications due to its simple construction and low manufacture cost. However, the doubly salient ...structure and the conventional square-wave control method lead to the large torque ripple in the DSEM. In this article, an improved direct instantaneous torque control (DITC) method is proposed to suppress the inherent torque ripple and enhance the torque capability of the DSEM. The maximum torque characteristics of the DSEM are obtained and analyzed with the finite-element method. Besides, the ideal phase current waveform to realize the low torque ripple is constructed according to the maximum torque characteristics. Then, the operation principle of the proposed DITC method is derived from the maximum torque characteristics. The proposed DITC method is implemented on a prototype of 12/8-pole DSEM drive system. The influence of the commutation angle parameters on the proposed DITC method is analyzed through simulation and experimental results. The simulation and experimental results indicate that the proposed DITC method can realize the smooth torque operation and high torque-ampere ratio simultaneously. Finally, the simulation and experiment under the step reference torque condition are performed to test the dynamic performance of the proposed DITC method.
The development of autonomous drones equipped with cameras and various sensors has paved the way for their application in agriculture and perimeter security. These aerial drones require specific ...power, acceleration, high torque, and efficiency to meet the demands of agricultural tasks, utilizing built-in brushless DC (BLDC) motors. However, a common challenge drone’s face is maintaining the desired speed for extended periods. Enhancing the performance of BLDC motors through advanced controllers is crucial to address this issue. This research paper proposes optimizing the size and speed of brushless DC motors for aerial vehicles using an adaptive fuzzy inference system and supervised learning techniques. When these drones carry loads, the BLDC motors must dynamically adjust the drone's speed. During this phase, the motors must control their speed and torque using artificial intelligence controllers like adaptive neuro-fuzzy inference systems (ANFIS) to enhance the drone's functionality, resilience, and safety. This research has conducted analyses focused on improving the performance of BLDC motors explicitly personalized for unmanned aerial vehicle (UAVs). The proposed method will be implemented using MATLAB/Simulink, expecting to significantly enhance the BLDC motor's performance compared to conventional controllers. Comparative analyses will be conducted between traditional and ANFIS controllers to validate the effectiveness of the proposed approach.
