• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.191-194
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• 1999

Recently, with the rapid development and demand for compactness of portable communications, the requirement for compact and low-cost filter is increasing. One of the methods for reducing size and cost is to use high dielectric constant and low loss dielectric material in filter. The other is new monoblock dielectric band-pass filter (BPF) which has holes in a single dielectric body without additional coupling elements. This structure effectively reduces the size and cost of the filters. For previous conventional coaxial type dielectric BPF, dielectric substrates were used for coupling between adjacent resonators and additional input and output ports were needed. Coupling between adjacent resonators of monoblock BPF can be otained via electrode pairs. Capacitances of electrode pair structure for coupling are intensively investigated by 3-D FEM. The BPF for PCS has been designed to have a 30 MHz pass-bandwidth with center frequency of 1855 MHz and an attenuation pole at below the passband using a commercial 3-D structure simulator.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.805-807
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• 2002

In this paper, a method for an accurate and fast transient analysis, which employs a single slot model for the rotor, is presented. The equivalent circuit parameters are extracted from a combined method of F. E. M and equivalent circuit on 1 slot rotor boundary condition. Two kinds of circuit parameters for each slip are applied to equivalent circuit controlled by variable-voltage variable- frequency. One is the constant parameters at rated speed, and the other is the parameters varying in accordance with slip-frequency. The computer characteristics of the suggested method for four-pole 1.5KW induction motor are compared with those of Equivalent circuit for the transient analysis.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.682-684
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• 2002

There is much room for consideration that the magnet design of UTM. When the vehicle runs 60mR curved line on test track, the ratio of cross section area changed to cross the magnet pole and rail. The ratio is reduced about 20% of the total magnet on one bogie. Therefor, magnet current is increased about 3.5A to maintain constant air gap. This paper suggest to margin of the magent design is 1.1 rather than rated levitation force.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.912-914
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• 2002

Single phase SRM(Switched Reluctance Motor) can not be started by itself and torque ripple is more generated than multi-phase SRM. But it is excited by single phase current and has very simple structure. Therefore it can be used in domestic appliance. Torque and speed of single phase SRM is controlled by adjusting exciting current and exciting section. Driver, which is composed with absolute encoder and DSP, is fabricated for control of exciting section on this paper. Then driving characteristics with exciting section is confirmed by using salient pole rotor type single phase SRM, which is fabricated in preceding research.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1190-1192
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• 2002

These days, electromagnetic radiation noise and switching losses of static converter become harmful. Many resonant inverters with radiation techniques solve their such problems. Auxiliary Resonant Commutated Pole Inverter (ARCP) was proposed. but it has two demerits. In circuit configuration. It isn't constructed by 2 in 1 IGET modules. Besides, control is complicated because of neutral point voltage control and boost current control. This paper proposes a new auxiliary resonant inverter which solved two demerits. In addition, it deals efficiency which compared with hard switching inverter and result of separation of power loss

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.604-606
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• 2002

Air-cored machines have a higher efficiency with high frequency. speed than iron-cored machine because of the iron losses which may produce too much heat as well as the copper losses occurred in the rotor winding. But air-cored machine is lower flux than iron machine. The nature of the machine from 'iron-cored' to 'air-cored' is a progressive feature in the machines. A general analysis of the fields that is applicable to all configurations is presented. Slotless machines have been applied for no ripple induced voltage. In this paper, slotless mahcines equipped with internal 4-pole amature winding. This paper pay attention to analyze flux density of air-cored and iron-cored synchrous machine analytically and compare flux density of aired-cored machine to iron-cored machine.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.32-36
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• 1990

LPM is a characterized motor to reciprocate linear motion for the office automation(OA), the factory automation(FA) and the field of information instruments because it can generate direct drive without any mechanical converter. For the design and analysis of permanent magnet type linear, pulse motor, it is therefore necessary to investigate the characteristics of magnetic flux distribution, static and dynamic thrust force, normal force, etc, by analyzing its magnetic circuit. This paper describes various useful methods for improving the characteristics of LPM. And these method is adopted on the PM and flat type, double side 2-phase 8-pole LPM.

• Proceedings of the KIEE Conference
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• 2006.04b
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• pp.167-169
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• 2006

대용량 BLDC 모터의 진동 및 소음의 원인은 영구자석과 슬롯 개구부 형상에 의한 코깅토크와 전류 파형에 의하여 발생하게 된다. 특히 대용량 BLDC의 경우 코깅토크에 의한 진동 및 소음의 영향이 상대적으로 큰 값을 가지게 된다. 따라서 코깅토크 발생원인 중 하나인 영구자석의 형상에 RSM(Response Surface Method) 최적화 이론을 적용하여 코깅토크 저감을 연구하였다. FEM과 RSM을 결합하여 영구자석의 형상을 최적화한 결과 코깅토크의 ripple이 25%이상 감소되었다.

• Proceedings of the KIEE Conference
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• 2006.04b
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• pp.194-196
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• 2006

This paper deals with design of a small-scaled permanent magnet generator (PMG) for wind power applications. First, this paper determines rated power and rated speed of the PMG from measured characteristics of wind turbines. Second, we derive analytical solutions for the open-circuit field in order to determine optimum magnet thickness and pole pitch/arc ratio. Third, on the basis of open circuit field solutions, stator magnetic circuit is designed. And then, a diameter of stator coil which agree with a required current density is calculated, and its turns are determined from the area of slot. Finally, finite element (FE) method is employed for validity of the designed PMG and, the back-emf measurements are also given to confirm the design.

• Proceedings of the KIEE Conference
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• 2006.04b
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• pp.313-315
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• 2006

Being controlled by a pole placement, levitation system should need many sensors that measure air-gap, velocity, acceleration, and so on. However, these sensors have observational errors by changed temperature. This paper proposed a output compensated command tracking controller for reducing the error and reducing sensors. Simulation results will be provided to show the validity of the proposed scheme.