• Journal of Institute of Control, Robotics and Systems
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• v.10 no.1
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• pp.30-41
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• 2004

This paper is concerned with the active vibration control of flexible cantilever beam system using electromagnetic farce actuator. The main objective of this paper is to propose the control algorithms and to implement the experimental setups for active vibration control. Dynamic equations of the electromagnetic actuator and the beam are combined to find the transfer function from the electromagnetic actuator to the laser sensor. The final transfer function is determined by considering only the first and second modes, and experiments confirm that this model works well. Several control algorithms are proposed and implemented on the experimental setups to show their efficacy. These include a PID control design, an optimal H$_2$ control design, and a fuzzy PID control design. Effectiveness and performance of the designed controller were verified by both simulation and experiment results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.979-982
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• 2003

In this study, because of change in electromagnetic force, deformation of the free surface motion of a magnetic fluid is changed. Deformation of the free surface motion of a magnetic fluid for the change in electromagnetic force is discussed and carried out theoretically and experimentally on the basis of Rosensweig Ferrohydrodynamic Bernoulli Equation. Objective of this study explicates free surface motion by electromagnetic force and planes to designed controller. To control free surface of magnetic fluid, it embody designed two-dimensional free surface form of magnetic fluid. By using this characteristics, they applied to oscillator for surface control, flow control, boundary layer control. Strength of magnetic field and height of free surface of magnetic fluid measure as a hall-effect sensor. As performing height control of magnetic fluid, the result will be presented possibility of free surface deformation control.

• Smart Structures and Systems
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• v.13 no.3
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• pp.419-434
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• 2014

In this paper, the electromagnetic damper (EMD), which is composed of a permanent-magnet rotary DC motor, a ball screw and a nut, is considered to be analyzed as a semi-active damper. The main objective pursued in the paper is to study the two degrees of freedom (DOF) model of the semi-active electromagnetic suspension system (SAEMSS) performance and energy regeneration controlled by on-off and continuous damping control strategies. The nonlinear equations of the SAEMSS must therefore be extracted. The effects of the EMD characteristics on ride comfort, handling performance and road holding for the passive electromagnetic suspension system (PEMSS) are first analyzed and damping control strategies effects on the SAEMSS performance and energy regeneration are investigated next. The results obtained from the simulation show that the SAEMSS provides better performance and more energy regeneration than the PEMSS. Moreover, the results reveal that the on-off hybrid control strategy leads to better performance in comparison with the continuous skyhook control strategy, however, the energy regeneration of the continuous skyhook control strategy is more than that of the on-off hybrid control strategy (except for on-off skyhook control strategy).

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1023-1027
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• 2004

Since the change of the radial electromagnetic force is a main cause of noise and vibration of the SRM, this paper proposes a method to reduce the change of the electromagnetic force of an SRM. The technique is based on the control of the current shape associated with each phase using switches of the converter to drive an SRM. And we analyze the relation between the derivative of the radial electromagnetic force and the phase currents. A simulation is given to demonstrate our results.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.227-232
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• 2003

As the most precision equipment requiring very strict vibration environment are vulnerable to the surrounding vibration condition, they adapt the passive or active vibration isolation system. When it comes to the passive isolation system, the resonance of the isolation system causes excessive resonance response, and finally results in the degrade the equipment performance. This paper deals with the active control method to control this resonance induced response, and includes the experiment on the active control for controlling the resonance response on the table against the excitation of the same frequency with the natural frequency of the isolation system. The electromagnetic actuator was designed and the control effect was verified by the experiment. The experiment showed that the electromagnetic actuator is effective for controlling the low frequency isolation resonance response of the precision equipment.

• Coupled systems mechanics
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• v.1 no.1
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• pp.39-57
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• 2012

This study intends to explore dynamic interaction behaviors between actively controlled maglev vehicle and guideway girders by considering the nonlinear forms of electromagnetic force and current exactly. For this, governing equations for the maglev vehicle with ten degrees of freedom are derived by considering the nonlinear equation of electromagnetic force, surface irregularity, and the deflection of the guideway girder. Next, equations of motion of the guideway girder, based on the mode superposition method, are obtained by applying the UTM-01 control algorithm for electromagnetic suspension to make the maglev vehicle system stable. Finally, the numerical studies under various conditions are carried out to investigate the dynamic characteristics of the maglev system based on consideration of the linear and nonlinear electromagnetic forces. From numerical simulation, it is observed that the dynamic responses between nonlinear and linear analysis make little difference in the stable region. But unstable responses in nonlinear analysis under poor conditions can sometimes be obtained because the nominal air-gap is too small to control the maglev vehicle stably. However, it is demonstrated that this unstable phenomenon can be removed by making the nominal air-gap related to electromagnetic force larger. Consequently it is judged that the nonlinear analysis method considering the nonlinear equations of electromagnetic force and current can provide more realistic solutions than the linear analysis.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.936-939
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• 2006

The pneumatic isolator is widely adopted for anti-vibration of precision measuring and manufacturing equipments. But, when the precision demand on anti-vibration is extreme or the load is moving, the performance of anti-vibration can not meet satisfaction. In these cases, as a complementary, active vibration suppression system can be added for advanced performance. In this paper, an active control system is presented, which uses electromagnetic actuators for vibration suppression. The anti-vibration characteristic of pneumatic isolator is analyzed for system modeling and actuator specifying. The modeling and the 3D dynamic simulation is performed for control system design. For the electromagnetic actuator design, the magnetic flex density and the current-force characteristic analysis are achieved.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.733-736
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• 2004

Actual trends in automotive industry lead to an increase use of lightweight structures imposing the need for high strength aluminum alloys with complex shape. In the electromagnetic stirring process, it has many merits which are the exact control ability about material processing and a good point of the protection of environment comparison with the mechanical stirring. The interface of cells consisting of primary particle formed by the electromagnetic stirring due to particle regrowth during cooling the alloy. By electromagnetic stirring process, the microstructure of material has a good point, also it can control the material processing exactly.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.254-258
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• 2004

Actual trends in automotive industry lead to an increase use of lightweight structures imposing the need fur high strength aluminum alloys with complex shape. In the electromagnetic stirring process, it has many merits which are the exact control ability about material processing and a good point of the protection of environment comparison with the mechanical stirring. The interface of cells consisting of primary particle formed by the electromagnetic stirring due to particle regrowth during cooling the alloy. By electromagnetic stirring process, the microstructure of material has a good point, also it can control the material processing exactly.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.12-14
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• 1999

Recently, the electromagnetic proportional valve has been widely used in order to control pressure and flow in such systems as NC machine and automatic facility. The linear electromagnetic solenoid used for proportional control valve ought to have hysteresis characteristic because of control the thrust force proportionably by input current. Therefore, in this study, we analysis the thrust force characteristics and established design for practical use, which allows Linear Pulse Motor(LPM) to be used as a driving system for electromagnetic proportional control valves.