Electromagnetic Suspension Research Articles

Non-contact Gripping of Thin Steel Plates by Electro Magnetic Suspension

Non-contact Gripping of Thin Steel Plates by Electro Magnetic Suspension

Modeling of Coupled Electric and Magnetic Circuits in Electromagnetic Suspension Vehicles

Modeling of Coupled Electric and Magnetic Circuits in Electromagnetic Suspension Vehicles

A new energy-feeding variable damping control strategy for electromagnetic hybrid suspension systems

Traditional energy-feeding suspensions exhibit a non-adjustable damping characteristic during energy recovery, which can compromise the dynamic performance of the suspension system. To overcome this issue, this paper proposes an energy-feeding variable damping control strategy (EFVD) predicated on an electromagnetic hybrid suspension system. This strategy aims to achieve adjustable damping during energy recovery, reducing energy losses while ensuring optimal suspension performance. Building on a half-vehicle suspension model, we construct a dynamic model of the electromagnetic hybrid suspension. By leveraging an enhanced hybrid-skyhook and ground-hook control algorithm (HSGH), we solve for the target control force. We then design a force distribution controller based on the EFVD strategy, aiming to optimize suspension dynamic performance and energy feeding efficiency. And we conduct a simulation study, measuring power supply efficiency and suspension dynamic performance as key evaluation metrics. The results demonstrate the superiority of the proposed EFVD strategy over conventional passive and active suspension control strategies, highlighting its effectiveness and reliability in maintaining dynamic performance while enhancing energy efficiency. This underscores the potential of the EFVD strategy as a practical solution for future suspension system design and energy management.

Refined disturbance observer based prescribed performance fixed-time control of high-speed EMS trains with track irregularities

High-speed Electromagnetic Suspension (EMS) train is continuously impacted by the irregularity of the track, which worsens the levitation performance of the train. In this paper, a composite control scheme for the EMS is proposed to suppress track irregularities by integrating a Refined Disturbance Observer (RDO) and a Prescribed Performance Fixed-Time Controller (PPFTC). The RDO is designed to estimate precisely the track irregularities and lumped disturbances with uncertainties and exogenous disturbances in the suspension system, and reduce input chattering by applying to the disturbance compensation channel. PPFTC is designed to converge the suspension air gap error to equilibrium point with prescribed performance by completing error conversion, and solve the fast dynamic issue of EMS. And the boundary of overshoot and steady-state is limited in the ranged prescribed. A theoretical analysis is conducted on the stability of the proposed control method. Finally, the effectiveness and reasonability of the proposed composite anti-disturbance control scheme is verified by simulation results.

Investigation of the Transverse Flux Linear Synchronous Motor Integrated With Propulsion, Levitation and Guidance for the Maglev Train

Conventional electromagnetic suspension (EMS) high-speed trains adopt linear synchronous motors (LSMs) and electromagnets together to provide propulsion, levitation and guidance (PLG) forces. In this paper, a new transverse flux linear synchronous motor (TFLSM) is presented for high-speed maglev trains, which can concurrently provide PLG forces. First, the topology and operating principle of TFLSMs are introduced. Second, the electromagnetic characteristics in the TFLSMs and conventional LSMs applied in high-speed maglev trains under the same dimensional conditions are compared and analyzed using the three-dimensional (3-D) finite element method (FEM). A quantitative comparison of the two motors is carried out to show the feasibility of TFLSMs in maglev transportation system applications. Third, the variations of electromagnetic forces in TFLSM with different mechanical parameters and input currents are calculated and analyzed. Finally, the test platform of the prototype TFLSM is built and experiments are conducted to validate the simulation results. Compared with the conventional LSMs, the levitation force generated by TFLSM is increased by 55% and the propulsion force is increased by 21%.

Characteristics Analysis of Novel Transverse Flux Linear Synchronous Motor for Maglev Transportation

The Maglev transportation mainly completes the propulsion, levitation and guidance functions, which generally require the application of linear motor. Based on this, a novel transverse flux linear synchronous motor is proposed in this paper which is integrated with propulsion, levitation and guidance. The whole structure and principle of the novel transverse flux linear synchronous motor are discussed. Then, the air gap magnetic flux density is calculated based on the equivalent current layer analysis method, and the propulsion and levitation are calculated with different operating times. Besides, the guidance force is calculated with different transverse displacements by using the Schwarz-Christoffel conformal mapping method. After the simulated of the finite element model, the analytical results of the forces are compared with the finite element method. Finally, all the calculated results of the propulsion, the levitation and the guidance are validated by an experimental prototype, which provide an electromagnetic theory analysis for electromagnetic suspension transportation that integrated with propulsion, levitation and guidance.

Decoupling Control for Module Suspension System of Maglev Train Based on Feedback Linearization and Extended State Observer

The suspension gap of the electromagnetic suspension maglev train is around 8 mm. In practice, it is found that the system gap fluctuations are amplified due to the inner coupling of the suspension module system in the maglev train. In addition, maglev trains are affected by load disturbances and parameter perturbations during operation. These uncertainties reduce the ride comfort. Therefore, it is necessary to propose a novel control strategy to suppress inner coupling while reducing the influence of uncertainties on the system. In this paper, a control strategy based on feedback linearization and extended state observer (ESO) is proposed to address this challenge. Firstly, the suspension module system model is established with parameter uncertainties and external disturbances. Additionally, the inner coupling of the suspension module is represented in this model. Subsequently, the feedback linearization method based on differential geometry theory is applied to reduce the effect of inner coupling. Meanwhile, the system uncertainties are transformed into equivalent disturbances by this method. Afterward, a linear ESO is designed to estimate the equivalent disturbances. Finally, a state feedback controller is used to achieve stable suspension and compensate for the disturbances. Simulation and experimental results show that the proposed decoupled control strategy significantly suppresses the influence of inner coupling and uncertainties on the system compared with the traditional PID control strategy.

Research on Stability Control Technology of Hazardous Chemical Tank Vehicles Based on Electromagnetic Semi-Active Suspension

Liquid sloshing in the tank can seriously affect the stability of hazardous chemical tanker trucks during operation. To this end, this paper proposes a solution based on an electromagnetic semi-active suspension system to prevent chemical spills and ensure safe driving of hazardous chemical tank vehicles. A comprehensive investigation was conducted across four domains: theoretical research, simulation model establishment, co-simulation platform construction, and simulation data analysis. Three fuzzy controllers were used to suppress the vibration of the tank vehicles, and a simulation study of the stability control of the tank vehicles under electromagnetic semi-active suspension was carried out. The results show that the electromagnetic semi-active suspension can significantly reduce the vertical, pitch, and roll vibrations of the tank vehicles by 17.60%, 25.78%, and 27.86%, respectively. The research results of this paper are of great significance for improving the safety and stability of hazardous chemical tanker trucks.

Electrically Interconnected Suspension and Related Technologies: A Comprehensive Review

<div>The electrically interconnected suspension (EIS) is a novel suspension system that has gained attention due to its potential to improve vehicle vibration control. This article provides a comprehensive review of EIS and related technologies. It starts with an overview of the research on hydraulic interconnected suspension (HIS) and its limitations. Then, it discusses the development of the electromagnetic suspension (EMS) and its advantages in adjusting mechanical characteristics. The article focuses on the electrical network and decoupling control characteristics of EIS, demonstrating the principle of synchronous decoupling control of multiple vibration modes. A comparison of the structure and control characteristics of EIS and HIS highlights the advantages of EIS in vehicle vibration control. The article concludes by identifying some unresolved issues and potential research areas to guide future studies on EIS, such as improving the controllability and energy efficiency of EIS systems.</div>

Fabrication of Electromagnetic Suspension System

The power generator electromagnetic suspension system is a system that converts vehicle bump generated linear motion & vibration, into electricity to be used in battery charging. General vehicle shock absorbers are used to simply absorb this energy without converting it to electricity. So here we put forth a way to use this free energy and store it for further needs such as vehicle lights, cooling, indicator lights etc. The devised prototype Suspension System uses the energy to generate electricity which is otherwise dissipated. In this work, process of arriving at the fabricated model of Suspension System for Power Generation is elaborated. The preliminary and existing techniques which help in regenerating energy dissipation in suspensions are discussed and the way they led to contrive the concept of prototype Suspension System is elucidated. With the concept, the derivation of specifications and the process of designing the Suspension System is delineated. The Suspension System generated a potential difference in the range of 125 mV to 350 mV.

Ultra-low frequency active vibration isolation in high precision equipment with electromagnetic suspension: Analysis and experiment

High performance vibration isolation requirement in the ultra-low frequency band for high precision equipment becomes more and more stringent. An active vibration isolation method is investigated to broaden the frequency band of isolation and improve the performance, in which an electromagnetic suspension is adopted to provide a static lifting force and an active control force. Naturally, the suspension is accompanied by a controllable negative stiffness. Two factors that might cause instability of the suspension system, i.e., the bias current and the base disturbance, are analyzed to give the stable region. The matching relationship between the currents in the upper and lower coils, and the mapping rules among the current, relative displacement, force and stiffness are discussed, respectively. The maximum base disturbance that the system can withstand is analyzed. On the basis of the theoretical analysis, the active position stabilization and vibration control methods are built and the performance is evaluated. Furthermore, experiments were conducted to verify the effectiveness of the active vibration isolation method. Numerical and experimental results demonstrate that the electromagnetic suspension is able to improve the vibration isolation performance in the ultra-low frequency range, where the transmissibility is below 0 dB in the entire frequency band and the initial vibration isolation frequency is less than 1Hz.

Multiobjective optimization for semi-active electromagnetic vehicle suspensions

Multiobjective optimization for semi-active electromagnetic vehicle suspensions

Study on Adaptive Sliding Mode Fault-tolerant Control of 1/4 Vehicle Electromagnetic Suspension

An adaptive sliding mode fault-tolerant manage approach is proposed to remedy the trouble of actuator acquire failure of the electromagnetic hybrid energetic suspension device and the hassle of automobile manipulate balance degradation induced by using the nonlinear pressure of spring and damper. The failure thing is chosen to symbolize the actuator fault size, and the actuator fault parameter mannequin is established. Combining sliding mode manipulate with adaptive control, an adaptive sliding mode fault-tolerant controller for lively suspension primarily based on an correct mannequin is designed. Based on the Lyapunov balance theory, the steadiness of the machine is proved; and the Gravity search algorithm (GSA) and linear matrix inequality (LMIS) are used to optimize the sliding floor parameters, and the most beneficial answer is chosen in accordance to the health function. The simulation effects exhibit that in contrast with passive suspension, the root capability rectangular values of sprung mass acceleration, suspension dynamic deflection, and tire dynamic load underneath adaptive sliding mode fault-tolerant manipulate approach decrease by way of 41.7%, 38.4%, and 36.5% respectively. It suggests that the designed adaptive sliding mode fault-tolerant controller is right and can enhance car experience comfort.

Reduction of Active Electromagnetic Suspension Magnetic Loss

Reduction of Active Electromagnetic Suspension Magnetic Loss

Multi-mode switching control of electromagnetic hybrid suspension based on human subjective sensation

This study proposes a multi-mode switching control strategy based on electromagnetic hybrid suspension (EMHS) to achieve the best relationship possible between the vehicle’s vibration reduction performance and energy consumption. The working modes of EMHS are divided into active, semi-active, and energy recovery modes according to the relationship between the root mean square of weighted acceleration and the human subjective sensation. The two key switching parameters of the analysis sampling interval and switching judgment times are introduced to optimize the switching conditions and reduce the deterioration of comfort and handling stability caused by frequent system switching in mode switching decisions. In the sub-modes, it’s designed that an LQG main control loop uses an ant colony algorithm to optimize parameters to obtain the ideal output force. And inner-loop control strategies in active and semi-active modes are designed so that the actual force output by the actuator tracks the ideal force. The results show that the multi-mode switching control strategy can switch the EMHS reasonably in the three modes and achieve good vibration reduction performance. The RMS of SMA, SDD, and TDL are reduced by 27.5%, 6.3%, and 17.6%, respectively under the variable conditions road.

Analysis of the operation of electromagnetic bearings in the difference of the center of the magnetic system relative to the axis of rotation and variations of the supply voltage

The article sets the task of reducing the consumption of electrical energy by electromagnetic bearings. To achieve this goal, it is proposed to shift the center of the magnetic system of bearings that compensate for the weight of the rotor relative to the axis of rotation. The displacement value is assumed to be equal to half the clearance value in the safety bearings of the unit under consideration. A mathematical model of a radial electromagnetic bearing, its design scheme, taking into account the displacement of the center of the magnetic system relative to the axis of rotation, a block diagram of a three-loop control system and formulas for calculating the parameters of regulators are presented. Regulator settings for a specific type of electromagnetic bearings are determined. A calculation model has been developed that makes it possible to study the operation of an electromagnetic bearing when the center of the magnetic system is displaced relative to the axis of rotation and the supply voltage is varied. The results of simulation in the Matlab Simulink software environment of the process of rotor ascent from safety bearings and rotor levitation in a displaced state at different values of the supply voltage are given. It is shown that the voltage reduction by 16.7% ensures stable operation of the electromagnetic suspension of the rotor in all possible modes. Therefore, shifting the center of the magnetic system can reduce the power consumption of electromagnetic bearings by 30%.

Improved SEM Current Ringing Suppressor for Maglev Trains

In electromagnetic suspension (EMS) systems, the air gap between the suspension electromagnet (SEM) and steel track is adjusted by changing the electromagnetic attraction force, which is accomplished by controlling the maglev chopper (MC). When switching the power electronic devices of the MC, SEM current ringing tends to occur, which is harmful to the whole EMS system. A conventional current ringing suppressor (CRS) deteriorates the SEM port voltage ringing, which may accelerate the aging process of SEM insulation or even directly result in a breakdown fault. Herein, to explore the generation mechanism of SEM current ringing, a third-order equivalent circuit model of the suspension electromagnet-maglev chopper (SEM-MC) system is established by using the field-circuit coupling analysis technique. A series of simulations and experiments have been undertaken to verify the validity of the built circuit model, and the deviation between the simulation and experimental results is acceptable. As the influencing factors of SEM current ringing are analyzed based on this third-order equivalent circuit model, an improved CRS, i.e., hybrid inductor-resistor CRS, is proposed to avoid deteriorating the SEM port voltage ringing and protect the SEM insulation. Finally, the feasibility of the proposed hybrid inductor-resistor CRS is verified by corresponding experiments.

Bond Graph-Based Modelling and Control of Electromagnetic Levitation System Using Firefly Optimization

This paper focuses on the modelling and control of an electromagnetic suspension using the bond graph tool. This technique combines graphical and relational aspects to establish connections between bond graph elements, particularly in deducing junction relationships and employing bicausal inversion for trajectory tracking controller design. To determine the controller parameters, we utilized a meta-heuristic method called Firefly for optimization, thus avoiding the need for trial and error. The simulation was conducted using 20-Sim software and a Matlab/Simulink script, which yielded improved results. This paper presents an initial contribution that demonstrates the integration of meta-heuristic optimization and the bond graph tool for parameter selection in 20-sim simulation software.

Research on Magnetic Characteristics and Fuzzy PID Control of Electromagnetic Suspension

This paper proposes an electromagnetic suspension with an electromagnetic actuator, which can improve the riding comfort and stability of the vehicle without changing the safety of traditional MacPherson suspension. First, the electromagnetic suspension structure is introduced, and the principle of the proposed actuator is described in detail. Second, a magnetic flux density model of a single PM ring (permanent magnetic ring) and a magnet assembly are built, and a theoretical analysis of the magnetic flux density is carried out for comparison. Then, the magnetic flux distribution of the magnetic field is simulated and analyzed using the finite element method (FEM), and is compared with theoretical and other experimental data. Finally, a vehicle dynamics model with 7 DOF is built, and vehicle simulations based on the fuzzy PID algorithm are carried out on a C-grade road surface and a deceleration strip. The theoretical results and simulation analyses of the FEM indicate that compared with the MacPherson suspension, the root mean square values of the acceleration of centroid acceleration for the electromagnetic suspension are increased by 59.08% and 33.34%, respectively, on a C-grade road surface and a deceleration strip, and other physical quantities have also been improved. The structure and characteristics of the proposed electromagnetic suspension that improve the riding comfort of the suspension and enhance the stability of the MacPherson suspension are feasible.

Neural Network Trajectory Tracking Control on Electromagnetic Suspension Systems

A new adaptive-like neural control strategy for motion reference trajectory tracking for a nonlinear electromagnetic suspension dynamic system is introduced. Artificial neural networks, differential flatness and sliding modes are strategically integrated in the presented adaptive neural network control design approach. The robustness and efficiency of the magnetic suspension control system on desired smooth position reference profile tracking can be improved in this fashion. A single levitation control parameter is tuned on-line from a neural adaptive perspective by using information of the reference trajectory tracking error signal only. The sliding mode discontinuous control action is approximated by a neural network-based adaptive continuous control function. Control design is firstly developed from theoretical modelling of the nonlinear physical system. Next, dependency on theoretical modelling of the nonlinear dynamic system is substantially reduced by integrating B-spline neural networks and sliding modes in the electromagnetic levitation control technique. On-line accurate estimation of uncertainty, unmeasured external disturbances and uncertain nonlinearities are conveniently evaded. The effective performance of the robust trajectory tracking levitation control approach is depicted for multiple simulation operating scenarios. The capability of active disturbance suppression is furthermore evidenced. The presented B-spline neural network trajectory tracking control design approach based on sliding modes and differential flatness can be extended to other controllable complex uncertain nonlinear dynamic systems where internal and external disturbances represent a relevant issue. Computer simulations and analytical results demonstrate the effective performance of the new adaptive neural control method.