To improve ride comfort and address the limited fail-safe capability and energy utilization of electromagnetic actuators in commercial vehicle cab suspensions, a hybrid electromagnetic linear actuator (HELA) is proposed. HELA coaxially integrates a hydraulic damper and an electromagnetic linear actuator, enabling active force generation, energy regeneration, and passive fail-safe damping within the original installation space. A three-degree-of-freedom quarter-cab suspension model is established to determine the passive damping coefficient and actuator force, stroke, and velocity requirements using linear quadratic regulator (LQR) control. From the initial structure, Morris sensitivity analysis and hierarchical optimization target seven key parameters to avoid magnetic saturation, reduce radial size, and balance thrust output with detent-force suppression. The optimized actuator reduces detent force by 50.13%, increases average thrust by 8.09% to 487.75 N, and lowers the thrust ripple ratio to 7.42%. On a Class C road at 54 km/h, the hybrid mode achieves peak/average regenerative powers of 93.02/5.02 W and reduces net actuator energy consumption by 83.4%. Prototype tests confirm short-circuit damping capability and an approximately linear current-thrust relationship, with the measured thrust showing reasonable consistency with finite-element predictions.

To improve the control performance of linear motors with external perturbations and input saturation, this paper designs an anti-saturation fixed-time integral sliding mode control strategy based on a fixed-time disturbance observer (FxITSMC-FxDO). First, the parameter uncertainties and external disturbances are viewed as composite disturbances. A fixed-time disturbance observer is designed to estimate and compensate for them in real-time, which effectively suppresses chattering by estimating the lumped disturbances. Second, by combined-time theory and integral sliding-modetrol, a fixed-time integral sliding-mode controller is designed to accelerate the convergence speed. Moreover, a non-linear anti-saturation compensator is designed based on the actuator saturation effect parameter to enable the system to exit the saturation region quickly. The fixed-time convergence property of the closed-loop system is proved based on the Lyapunov stability theorem. The experimental results show that the proposed control method effectively improves the control accuracy, response speed, and robustness of linear motors. The step response time of the direct drive permanent magnet linear motor is improved by 16.0% compared to the integral sliding mode control method and 12.5% compared to the finite-time sliding mode control method. In sine target tracking, steady-state accuracy is enhanced by 31.3% over ITSMC and 24.1% over FITSMC-FDO. Furthermore, as the sinusoidal tracking frequency increased from 0.5 to 4 Hz, the proposed control strategy maintained relatively low increases in ITAE and ISE.

A displacement estimation technique based on BP neural networks is suggested to enhance the super-twisting sliding mode observer in order to address the installation challenges,cost rise,and stability reduction of electromagnetic linear actuators induced by the usage of displacement sensors.Combined with an adaptive integral robust control algorithm,the displacement sensorless control of the electromagnetic linear actuator is realized.A non-singular fast terminal sliding mode surface is designed with the continuous hyperbolic tangent function as the switching function in order to reduce the buffeting phenomenon and enhance the displacement estimation performance of the super-twisting sliding mode observer;in terms of the observer's parameter adjustment,the BP neural network is designed to dynamically adjust the super-twisting sliding mode observer's gain using the input of the mover speed.The motion control performance test platform of the electromagnetic linear actuator is established,and the displacement estimation and feedback control results are analyzed.The results show that the maximum displacement estimation error of the improved sliding mode observer is reduced by 16.22%under the step condition and 9.10%under the sine condition with the frequency of 2 Hz compared with the super-twisting sliding mode observer;the control performance of displacement sensorless control is equivalent to that of displacement sensor control.The steady state error of the two is 0.03 mm under the 8 mm step condition,and the maximum error is 0.43 mm under the sinusoidal condition with the frequency of 2 Hz.This proves the effectiveness and practicability of the displacement sensorless control of the electromagnetic linear actuator based on an improved super-twisting sliding mode observer.

In order to solve the problem of magnetic field distortion caused by the high magnetic permeability of the end cover of moving coil electromagnetic linear actuator, which leads to fluctuations in the thrust of actuator and the inaccuracy of the analytical solution, a magnetic field analytical modeling method combining the pseudo-period method and the magnetic vector potential method was proposed. Considering the end effect, the virtual array was extended to both sides of the permanent magnet and winding array in the pseudo-period to compensate the end magnetic circuit, and the analytical expressions of the magnetic field distribution of the open circuit and armature reaction were derived in the form of Fourier series. On this basis, the analytical expression of electromagnetic thrust was derived by Lorentz force method. The results show that compared with finite element simulation, the maximum error of the analyzed thrust value is 9.04% when ignoring the end cap, while the maximum error of the analyzed thrust value is 3.97% when considering the end effect, which verifies the effectiveness of the proposed method; the average relative error of the experiment is 3.77%, which verifies the correctness of the proposed method. This method can effectively consider the influence of the end cap on the magnetic field distortion, which provides theoretical reference for solving the electromagnetic characteristics of the electromagnetic linear actuator quickly and accurately, optimizing the structural parameters and the control process.

Electromagnetic linear actuators are widely used in direct drive systems. To mitigate the effects of internal parameter disturbances and external uncertainties, this paper proposes an improved active disturbance rejection sliding mode control method. The position loop employs active disturbance rejection control with an enhanced sliding mode control rate and a dual hierarchy expanding state observer, while the current loop uses Proportional-Integral (PI) control. System stability is verified using Lyapunov theory. The dual hierarchy linear expansion state observer effectively estimates position and velocity, while a terminal complementary sliding mode controller replaces the traditional linear controller to enhance response speed and accuracy, reducing chattering associated with conventional sliding mode control. Simulation and experimental results show that compared with the traditional ADRC and ISM-ADRC, the improved method reduces the steady-state error by 45.5% and 29.4%, respectively. The maximum error at 1 hz and 2 hz sine conditions is 0.50 mm and 0.52 mm, respectively. In addition, the root mean square error (RMSE) was reduced by 15.13% and the maximum error was reduced by 7.4% compared to the traditional ADRC, showing greater robustness under different loads. These results verify the effectiveness and practicability of the proposed electromagnetic linear actuator control method.

Aiming at the difficulty in selecting the weight matrix of model predictive control (MPC) algorithm in the path tracking control of self-driving vehicles, which leads to low control accuracy and low operating efficiency of the controller, a genetic particle swarm optimization model prediction control (GA-PSO-MPC) algorithm was proposed. Firstly, a vehicle dynamics model was established, the objective function was determined according to the dynamics model and constraints were added to design the MPC controller; Secondly, the genetic particle swarm optimization algorithm (GA-PSO) was used to optimize the weight matrix of the model predictive controller; Finally, a Carsim/Simulink simulation platform was built to compare the tracking performance of GA-PSO-MPC controller with traditional MPC controller, and the simulation of path tracking control under different working conditions with different speeds was completed. The results show that the convergence speed of the controller proposed in this paper after the optimization of the weight matrix by GA-PSO algorithm is improved by 68.85%, and the maximum lateral error is reduced by 63.9%. The operation efficiency and tracking accuracy of the GA-PSO-MPC controller are better than that of the traditional MPC controller at various vehicle speeds, which can effectively solve the problems of low operation efficiency and insufficient tracking accuracy of the traditional model predictive controller.

Owing to its high energy efficiency, regenerative capability, and fast dynamic response, the Electromagnetic Energy-Feeding Shock Absorber has found widespread application in automotive suspension control systems. To further improve thrust control precision, this study presents a sliding mode thrust controller designed using an improved Gray Wolf Optimization algorithm. Firstly, an improved exponential reaching law is adopted, where a saturation function replaces the traditional sign function to enhance system tracking accuracy and stability. Meanwhile, a position update strategy from the particle swarm optimization (PSO) algorithm is integrated into the gray wolf optimizer (GWO) to improve the global search ability and the balance of local exploitation. Secondly, the improved GWO is combined with sliding mode control to achieve online optimization of controller parameters, ensuring system robustness while suppressing chattering. Finally, comparative analyses and simulation validations are conducted to verify the effectiveness of the proposed controller. Simulation results show that, under step input conditions, the improved GWO reduces the rise time from 0.0034 s to 0.002 s and the steady-state error from 0.4 N to 0.12 N. Under sinusoidal input, the average error is reduced from 0.26 N to 0.12 N. Under noise disturbance, the average deviation is reduced from 2.77 N to 2.14 N. These results demonstrate that the improved GWO not only provides excellent trajectory tracking and control accuracy but also exhibits strong robustness under varying operating conditions and random white noise disturbances.

Abstract To accurately simulate the motion characteristics of a reed valve and the changes in flow field in an exhaust chamber, a fluid-structure coupling model of an electromagnetic direct drive air compressor during the exhaust process was established and simulated. The alteration of the flow field within the exhaust chamber is under examination. The transient numerical simulation of the flow field in the exhaust procedure is conducted to reduce the computational model's time complexity and provide an immediate analysis of the exhaust processThis paper explores the effects of altering valve lift and relative pressure loss given different valve parameters and exhaust pressure levels. The findings reveal that when the valve plate thickness is 0.2mm and the valve section width is 3.5mm, the airflow hindrance is significantly minimized. With the valve plate unloaded, the gas flow restriction's impact on gas flow is negligible. This paper presents a theoretical basis for designing exhaust valves for electromagnetic direct-drive air compressors.

The motor parameters of permanent magnet synchronous motor (PMSM) can be mismatched in operation due to temperature variations and magnetic saturation. The parameter mismatch leads to a significant decrease in the robustness of traditional deadbeat predictive current control (DPCC), which leads to issues such as current static error and motor vibration noise. In this paper, a model-free predictive current control (MFPCC) method based on an improved sliding mode disturbance observer (SMDO) was proposed. The method estimated the total disturbance of the system using the improved SMDO, which could effectively suppress sliding mode chattering and accelerate the convergence speed of current errors. Subsequently, the predicted control voltage was calculated using a hyper-local model and compensated for the time delay. The experimental results demonstrated that the improved MFPCC-SMDO method generated lower motor noise compared to the traditional DPCC method when the controller’s inductance parameters are mismatched.

To improve the control precision and stability of Direct-Drive Permanent Magnet Linear Motor (DPMLM) with frictional nonlinearity and uncertain disturbances at a low speed, an adaptive robust integral sign error control algorithm based on friction compensation of dual nonlinear observer is proposed in this study. An improved LuGre friction model is established to describe the friction phenomena of the system. The dual nonlinear observer is designed to observe the internal frictional state of the model. A parameter adaptive law is designed to perform parameter estimation of structured uncertainty. Robust integral of the sign of the error (RISE) term is designed to overcome the frictional nonlinear disturbances. The friction nonlinearity and parameter uncertainty are compensated by feedforward compensation. The bounded stability of the proposed controller is proved by Lyapunov stability theory. As suggested by the experimental results, RMSE index decreased by 10.8% and the control precision was improved effectively by the proposed control algorithm at a low speed.

In this paper, a novel electro-hydraulic system (EHS) with a direct-drive pump based on a high power-density moving-coil electromagnetic linear actuator (EMLA) is proposed. Based on the analysis of the EHS, a multidisciplinary optimization method based on the multi-objective game theory is proposed to optimize the static and dynamic performance of the EMLA concurrently. Aiming at the continuous disturbance of the EHS, an improved terminal sliding mode control (ITSMC) based on the improved exponential reaching law is designed. The robust differentiator and super-twisting disturbance observer are combined to compensate for the system. The result proves the feasibility of the novel EHS. The multidisciplinary optimization method is effective. The maximum electromagnetic force increased by 17.91%, and the electromagnetic force fluctuation rate decreased by 5.91% compared with the single discipline scheme, respectively. Compared with NTSMC method and PID method, the ITSMC method has higher response speed and control accuracy under the condition of nonlinear force disturbance and signal noise. The ITSMC method effectively improves the robustness of the control system under complex conditions.

面向新工业改革与发展,新经济新技术对新工科人才培养的需求,山东理工大学"新能源汽车工程"新工科专业从"知识、能力、素质、价值"等维度出发,基于知识探究、能力培养、人格养成、价值引领"四位一体"的育人理念,从"基本、提升、创新"三个阶段,构建了具有逻辑性、体系化的"三阶四维"人才培养目标达成矩阵.基于新工科人才核心能力培养,实践了以"项目驱动"为主体的能力培养顶层设计、企业全过程参与的"一个目标、两个主体、三个核心、四个层面、八项举措"的产教协同育人体系、全覆盖的"四维四元"融合创新创业能力培养体系、"以学生为中心"的面向产出的教学模式改革与质量监控反馈机制,在新工科人才培养中发挥了重要 作用.

Nonlinear electromagnetic force is a common phenomenon in electromagnetic linear actuators (EMLA). This nonlinearity limits the application in high-precision control systems. For facilitating the controller design, the influencing factors of nonlinear electromagnetic force were analyzed, and the quadratic polynomial with unknown weights was designed to approximate the nonlinear relationship among electromagnetic force, excitation current and displacement. An adaptive integral robust control algorithm based on electromagnetic force compensation (AIRC-FC) was designed, which combined the adaptive control law of electromagnetic force nonlinear compensation, stable feedback and error signal continuous integral robust control. The tracking performance and the adaptability of the EMLA with and without compensation control were analyzed under different loads. The results show that AIRC-FC improve the tracking performance of the EMLA effectively, and maintain high control accuracy under different loads.

The active suspension has undoubtedly improved the performance of the vehicle, however, the trend of "low-carbonization, intelligence, and informationization" in the automotive industry has put forward higher and more urgent requirements for the suspension system. The automotive industry and researchers favor active energy regeneration suspension technology with safety, comfort, and high energy regenerative efficiency. In this paper, we review the research progress of the structure form, optimization method, and control strategy of electromagnetic energy regenerative suspension. Specifically, comparing the pros and cons of the existing technology in solving the contradiction between dynamic performance and energy regeneration. In addition, the development trend of electromagnetic energy regenerative suspension in the field of structure form, optimization method, and control technology prospects.

针对电磁直线执行器应用中由于位移传感器而产生的结构紧凑性下降、成本高以及可靠性降低等问题,提出了一种基于最小二乘支持向量机(LSSVM)的位移估算方法.应用多目标粒子群优化算法,以准确度和均方根误差(RMSE)为优化目标对正则化参数和核宽度参数进行多目标优化;在特定工况下训练模型.模型应用与仿真实验验证结果表明:在不同负载力工况下估算控制准确度为98％以上,RMSE为3×10-4以下;以不同位移控制目标对电磁执行器进行控制,准确度为98％以上,RMSE为3×10-4以下.

AlCrFeNiMoNb high-entropy alloys were successfully coated onto a ZM5 alloy using high -velocity air fuel spray (HVAF). Microcomputed tomography(micro-CT) results revealed that the porosity of the coating was only 0.36%, which demonstrates the coating has a highly dense structure. The average microhardness of high-entropy alloys coating was > 5 times greater than that of the ZM5 alloy substrate. The changes of ZM5 substrate microhardness can be attributed to dynamic recrystallisation. The corrosion potential (E-corr) of the AlCr-FeNiMoNb coating was improved to approximately similar to -0.998 V and the corrosion current (I-corr) of the coating significantly decreased by two orders of magnitude. The wear volume loss of the coating was similar to 15 times lower than that of the ZM5 substrate. This indicates that the coating of the AlCrFeNiMoNb high-entropy alloy on the ZM5 substrate significantly improved the wear resistance of the ZM5 alloy. The ZM5 alloy surface had better corrosion and wear resistance properties owing to the protection offered by the AlCrFeNiMoNb high -entropy alloy. (c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

In this study, the nucleation and evolution of Mo-rich Laves phase particles in 9.5Cr-1.5MoCoVNbNB heat-resistant steel during tensile rupture testing at 620 degrees C were investigated using transmission electron micro-scopy (TEM) and atom probe tomography (APT). Laves phase particles have two nucleation mechanisms along the martensite lath boundary:(1) the formation of Laves phase particles alone on the boundary and their growth in one orientation and (2) the nucleation of Laves phase particles adjacent to M23C6 carbides without a specific growth orientation. Analysis of the TEM, energy dispersive X-ray spectroscopy, (EDS), and APT results revealed that deformation facilitated pipe diffusion and provided more sites for the nucleation of the Mo-rich Laves phase. In addition, it was found that stress resulted in a different evolution of the Laves phase adjacent to the M23C6 carbides compared to that occurring during aging at the same temperature. Further, the Laves phase particles nucleated at the interface of the coarsening M23C6 carbides and eventually wrapped around the nearby carbides, resulting in the elemental redistribution of Mo and Cr. In particular, the APT results indicate that the nucleation of the Mo-rich Laves phase on the M23C6 carbide interface during tensile rupture is because of Si and P enrichment around the carbides.

为解决电磁执行器换挡运动时由于磁场不均匀及温升问题而引起的换挡驱动力下降问题,对执行器驱动力及损耗特性进行了仿真研究;根据仿真结果对不同位置下的力常数进行方程拟合,为模拟执行器各部件温升变化,设计了执行器四热源等效热路;针对两种工作特性引起的驱动力下降问题,设计了基于执行器工作特性的补偿控制.结果表明,相比于P ID控制,补偿控制可有效补偿执行器驱动力损失,在常温和45℃下,执行器换挡速度分别提升了22％和20％.

针对永磁同步电机因参数扰动、采样延迟、模型失配导致电流控制误差问题,提出基于滑模干扰观测器的改进无差拍电流预测控制.通过将模型参数不匹配引起的扰动引入到电机的电压方程中,构建滑模扰动观测器观测系统扰动;针对滑模控制的抖振问题设计了以sgn为基础的二阶趋近律消除固有抖振问题,并证明了控制器的稳定性;将滑模观测器中的预测电流代替采样电流解决控制延时的问题;将观测估计的系统扰动通过前馈补偿的方式与无差拍电流预测控制相结合,进而提高无差拍电流控制的参数鲁棒性.结果表明:在参数扰动和模型失配时,提出的控制方法可以有效补偿系统扰动,系统稳态误差减小,有效提高了系统鲁棒性.

In this study, to enhance the frequency-flow characteristics of the novel electromagnetic direct-drive pump (EDDP). An adaptive disturbance observer-based improved super-twisting sliding mode control (ISTSMC-ADOB) is proposed to address the problem in which the response quality is deteriorated by factors such as parameter mismatch and disturbance. An adaptive disturbance observer (ADOB) is designed to achieve adaptive compensation, avoid the use of high-gain feedback, and extend the applicability of the conventional disturbance observer. An improved super-twisting sliding mode control (ISTSMC) based on the fast terminal sliding mode algorithm is designed to ensure faster convergence of the error in finite time. By combining the ADOB with the ISTSMC, the conservative parameter selection of the sliding mode control (SMC) is avoided, and the accuracy and robustness are further strengthened. The stability is analyzed based on Lyapunov. The results show that the proposed method effectively improves the steady-state accuracy, response speed, and robustness in trajectory tracking of the electromagnetic linear actuator for the EDDP. This further enhances the frequency-flow characteristics of the system.