• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1311-1318
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• 2015

This paper introduces a novel topology and an effective control strategy for a shunt hybrid power filter (SHPF) to simultaneously compensate harmonic currents and reactive power. The proposed SHPF topology is composed of an LC passive filter tuned to the 7^th harmonic frequency and a small-rated active filter connected in parallel with the inductor L_pf of the LC passive filter. Together with the SHPF topology, we also propose a control strategy, which consists of a proportional-integral (PI) controller for DC-link voltage regulation and a PI plus repetitive current controller, in order to compensate both the harmonic current and the reactive power without the need for additional hardware. Thanks to the effectiveness of the proposed control scheme, the supply current is sufficiently compensated to be sinusoidal and in-phase with the supply voltage, regardless of the distorted and phase lagging of the load current. The effectiveness of the proposed SHPF topology and control strategy is verified by simulated and experimental results.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.954-955
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• 2008

In this paper, the voltage harmonics are investigated in terms of the voltage sag versus the time constants of electric machinery under the source voltage variation condition. The electric machinery and compensation equipment are established on the proposed design scheme based on voltage quality effect assessment technology. It have been analyzed how the variation of harmonic order, the output current, the DC-Link voltage and the induction motor speed is carried out under the voltage sag and switching frequency variation.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.958-959
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• 2008

This paper is proposed a high performance speed control of the Interior Permanent Magnet Synchronous Motor through the Neural Network SV-PWM. SV-PWM is controlled using Neural Network control. SV-PWM can be maximum used maximum dc link voltage and is excellent control method due to characteristic to reducing harmonic more than others. Neural Network control has a advantage which can be robustly controlled. Simulation results are presented to show the validity of the proposed algorithm.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.978-979
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• 2008

본 논문에서는 TMS320F2812를 이용하여 연료 전지 BOP(Balance of Plant) 내장 터보 블로어로 쓰이는 영구자석 동기전동기의 센서리스 공간 벡터 제어를 구현하였다. 고속으로 회전하는 회전자의 위치 및 속도는 측정하기가 어려우므로, 전류를 이용하여 위상 및 속도를 추정하였으며, 이 알고리즘을 Digital Signal Processor(DSP) 상에서 구현하였다. 전류 측정시 노이즈에 의한 영향을 최소화하기 위해 외부에 12bit급 AD컨버터인 AD7891을 장착하였다. 데드타임 보상 및 dc-link 전압 리플 보상을 적용하였고, 정격 속도 100,000rpm에서 영구자석 동기전동기를 구동하였다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1058-1059
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• 2015

This paper describes a low-voltage ride-through method for the permanent magnet synchronous generator (PMSG) wind turbine system at a grid fault. The generator side converter regulates the DC link voltage instead of the grid side converter by storing the surplus active power in the rotor inertia during grid fault by the sliding mode controller. The grid side converter controls the grid active power keeping a maximum power point tracking. Simulation results for small scale PMSG wind turbine verify the efficiency of the control method.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.05a
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• pp.391-394
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• 2008

This paper is proposed a high performance speed control of the synchronous reluctance motor through the artificial intelligent SV-PWM. SV-PWM is controlled using fuzzy control that is artificial intelligent control. SV-PWM can be maximum used maximum dc link voltage and is excellent control method due to characteristic to reducing harmonic more than others. Fuzzy control has a advantage which can be robustly controlled. Simulation results are presented to show the validity of the proposed algorithm

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1590-1595
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• 2003

Direct drive servovalve(DDV) is a kind of one-stage valve since the rotary motion of DC motor is directly transferred to the linear motion of valve spool through the link. Since the structure of DDV is simple, it is less expensive, more reliable and offers reduced internal leakage and reduced sensitivity to fluid contamination. However, the flow force effect on the spool motion is significant such that it induces large steady-state error in a step response. If the proportional control gain is increased to reduce the steady-state error, the system becomes unstable. In order to satisfy the system design requirements, the lead-lag controller is designed using the complex method that is one kind of constrained direct search method.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.551-554
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• 2002

This paper describes a new interactive inverter between a photovoltaic(PV) array and single-phase utility that avoid the bulky input (60Hz) transformer on the AC side. The interface employs a pwm boost converter on the DC side followed by a pwm current-forced single-phase rectifier for injecting the power from the PV array into the mains. The current waveform at the AC side remains sinusoidal and exactly in phase at all time. The circuit also has the advantage of requiring fewer switching device than high-frequency link system. This paper describes modeling of PV array and new system topology. Simulation results on the performance of the connection are also presented.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.746-749
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• 2002

This paper presents a new control method for the high frequency electronic ballast which is operated with raw rectified dc link using diode bridge. For the commercial electronic ballast, proper ac input power factor and crest factor of the lamp current are required. The most ballast, therefore, has a active or passive power factor collection (PFC) circuit. With the proposed method, it can be achieved simultaneously that grater than 0.9 of input power factor and less than 1.85 of lamp current crest factor without any PFC circuit. In this paper, the proposed ballast control scheme and the experimental results for the application to the fluorescent lamp are described.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.339-341
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• 2006

The regenerating energy of the servo system is mostly consumed as heats through the regenerating resistors. For the response of the servo system to be more improved, the paper proposes the boost inverter using the regenerating energy, The proposed boost inverter has the additional capacitor installed on the DC-link circuit for charging the regenerating energy from the load. To get the better response of the servo system, the charged regenerating energy can be shortly re-applied to the output side as the finite impulse voltage, which can be controlled from information of reference voltages and feedbacked currents. It is verified by PSIM simulator that the response characteristics of the servo system using the proposed boost inventer is improved, comparing to that using the general inverter.