• Journal of Electrical Engineering and Technology
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• v.8 no.3
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• pp.595-602
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• 2013

An air circuit breaker (ACB) with novel double-breaker contact and permanent magnet actuator (PMA) is presented. Three-dimensional (3-D) finite element method (FEM) is employed to compute the electro-dynamic repulsion forces, including the Holm force and Lorentz force, which are acting on the static and movable contacts. The electro-dynamic repulsion forces of different contact pieces are computed, illustrating there is an optimal number of contact pieces for the ACB being studied. The electro-dynamic repulsion force of each contact, which varies from the outer position to the inner position, is also computed. Finally, the contacts of the double-breaker are manufactured according to the analyzed results to validate the simulations.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.593-596
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• 2001

It is necessary for calculation of repulsion forces acting on the closed electric contacts flowing over-current, e.g. inrush current and overload currents, to do optimum design of switching devices. In this paper, the farces and flux densities generated by currents at the contact point when circuit breakers are in closed state are obtained by using 3D finite element methode. To be convinced of the results, we measure electrogmanetic repulsion forces on contacts by measuring voltage between opened contacts in MCCB.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.593-596
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• 2001

It is necessary for calculation of repulsion forces acting on the closed electric contacts flowing over-current. e.g. inrush current and overload currents, to do optimum design of switching devices. In this paper. the forces and flux densities generated by currents at the contact point when circuit breakers are in closed state are obtained by using 3D finite element methode. To be convinced of the results, we measure electrogmanetic repulsion forces on contacts by measuring voltage between opened contacts in MCCB

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.95-97
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• 1999

This paper describes electromagnetic repulsion force of multipolar axial magnetic field type electrodes for vacuum interrupter used in vacuum circuit breaker. It was distinguished that repulsion force of multipolar axial magnetic field type electrode in consideration of eddy current effect between upper electrode and lower electrode by finite element method. And it was found out that suitable contact weight of multipolar axial magnetic field type electrode for vacuum circuit breaker from repulsion force analysis results by finite element method.

• Proceedings of the KIEE Conference
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• 2003.10b
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• pp.137-140
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• 2003

To the optimization design of molded case circuit breakers(MCCBs), it is necessary and important to calculate the electro-dynamic repulsion force acting on the movable conductor. With 3-D finite element nonlinear analysis, according to the equations among current-magnetic field-repulsion force and taking into account the ferromagnet, contact bridge model is introduced to simulate the current constriction between contacts, so Lorentz and Holm force acting on the movable conductor and contact, respectively, can be integrated to calculate. Coupled with circuit equations, the opening time of movable contact also can be obtained using iteration with the restriction of contact force. Simulation and experiment for repulsion forte and opening time of five different configuration models have been investigated. The results indicate that the proposed method is effective and capable of evaluating new design of contact systems in MCCBs.

• Proceedings of the KIEE Conference
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• 2008.10c
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• pp.90-92
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• 2008

A novel solving technique has been developed to analyze the dynamic characteristics of high speed Thomson-coil arc eliminator. The electromagnetic repulsion actuator based on Thomson-coil is taken as the driving part of the arc eliminator, due to which, the opening and closing time is quite short compare to other type actuators. The electromagnetic repulsion actuator is composed of one repulsion plate and two fixed coils, corresponding to the opening coil and closing coil, respectively. The new solving technique is derived based on the equivalent electric circuit model of the system which is set up by dividing the repulsion plate into multi segments using adaptive segmentation method. This solving technique is applied to the dynamic characteristic analysis of electromagnetic repulsion actuators in high speed Thomson-coil arc eliminators. The calculation results are testified by the FEM calculation results and experiment results.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.711-713
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• 2001

MCCB(Molded Case Circuit Breakers) is a multi-function safety device which, unlike other forms of protection, combines many protection features in a single unit. This paper is the analysis of magnetic repulsion forces with the breaking current 11.28kA, 22.5kA, 38.9kA and 45kA.

• Proceedings of the KIEE Conference
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• summer
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• pp.1076-1078
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• 2004

This paper deals with eddy-current magnetic repulsion system. The passive system employing permanent magnets on the moving part maximizes levitation forces by using Halbach array and conducting plate. We predict force characteristics according to permanent magnet array and conducting bar

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.364-367
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• 2001

In this paper, an analysis of electromagnetic repulsion force is presented using 3D FEM considering eddy current. It is important for the optimum design of switching device to analysis electromagnetic repulsion forces generated by the interaction of the electric current and its own magnetic field on the closed electric contacts flowing over current. The validity of our analysis is confirmed by comparing analytic and experimental results.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1613-1615
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• 2005

Maglev equipped with permanent magnets on the moving part can be levitated by the magnetic repulsion between Halbach array and conducting plate when this vehicle is running. This paper deals with the fundamental principles of the eddy-current magnetic repulsion system and the force characteristics to the change of the permanent magnet array and conduction bar.