• 전자공학회논문지
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• 제51권6호
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• pp.271-275
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• 2014

회전하는 동기 좌표계 d-q 변환을 이용한 단상 능동 전력 필터의 새로운 제어기를 제안하였다. 힐버트 변환기를 사용하여 $90{\circ}$의 위상차를 가지는 두 개의 교류 신호를 만든다. 이 신호들을 회전하는 동기 좌표계 d-q 변환을 이용하여 기본파 성분을 직류로 변환할 수 있고 따라서 고조파 검출이 용이하다. 순시 유효 전력의 평균값을 구한다. 역률 보상을 하므로 전원 전류는 전원 전압과 동위상이다. 단상에서의 전력 공식으로부터 전원 전류의 크기를 알 수 있다. 능동 전력 필터의 보상 전류의 기준 신호는 전원 전류의 기준신호에서 부하 전류를 빼주면 구할 수 있다. 새롭게 제안된 제어기에 히스테리시스 전류 제어기를 적용하여 시뮬레이션 하였다. 능동 전력 필터가 부하전류의 고조파와 무효전력을 보상하여 전원 전류가 전원전압과 동위상이 되고 전원전류가 정현파에 가깝게 되는 것을 확인하였다. 힐버트 변환기는 전대역 여파기를 사용하여 구현하였다.

• Journal of Power Electronics
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• 제3권1호
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• pp.49-54
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• 2003

A novel control scheme of using a single electronic drive to synchronize two synchronous motors is investigated analytically. The developed control strategy extends the conventional vector control technology, Specifically, it utilizes the property that the motion of two motors can be independently controlled by the q-axis currents provided the desired q-axis currents can be achieved by adjusting physical armature currents. The latter part is indeed guaranteed by adding a position offset to one of the motors. This work has a potential of cost saving in practice where the cost of drive is a major concern.

• Journal of Power Electronics
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• 제11권3호
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• pp.375-380
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• 2011

A STATic synchronous COMpensator (STATCOM) is a shunt connected voltage source converter (VSC) based FACTS controller using Gate Turn Off (GTO) power semiconductor devices employed for reactive power control. The operation principal is similar to that of a synchronous condenser. A typical application of a STATCOM is voltage regulation at the midpoint of a long transmission line for the enhancement of power transfer capability and/or reactive power control at the load centre. This paper presents the modeling of STATCOM with twenty four pulse three level VSC and Type-1 controller to regulate the reactive current or the bus voltage. The performance is evaluated by transient simulation. It is observed that, the STATCOM shows excellent transient response to step change in the reactive current reference. While the eigenvalue analysis is based on D-Q model, the transient simulation is based on both D-Q and 3 phase models of STATCOM (which considers switching action of VSC).

• Journal of Power Electronics
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• 제3권1호
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• pp.33-39
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• 2003

This paper presents the self-commissioning for surface-mounted permanent magnet synchronous motor. The proposed strategy executes three tests with a vector controlled inverter drive system. To do this, synchronous d-q axes currents are appropriately controlled for each test. From the three tests, armature resistance, armature inductance, equivalent iron loss resistance, and emf coefficient are identified automatically. The validity of the proposed strategy is confirmed by experimental results.

• 한국안전학회지
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• 제16권2호
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• pp.51-56
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• 2001

This paper is proposed an efficiency optimization control algorithm for a synchronous reluctance motor (SynRM) which minimizes the copper and iron losses. fen exists a variety of combinations of d and q-axis current which provide a specific motor torque. The objective of the efficiency optimization controller is to seek a combination of d and q-axis current components, which provides minimum losses at a certain operating point in steady state. It is shown that the current components which directly govern the torque production have been very well regulated by the efficiency optimization control scheme. The proposed algorithm allows the electromagnetic losses in variable speed and torque drives to be reduced while keeping good torque control dynamics. Simulation results are presented to show the validity of the proposed algorithm.

• 조명전기설비학회논문지
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• 제29권9호
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• pp.89-95
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• 2015

This paper presents a current sensorless maximum torque control of a synchronous reluctance motor drive. Stator current and current angle vs. maximum torque are obtained using measured d-axis and q-axis inductances. Then, d and q-axis stator voltage references for current sensorless maximum torque control are calculated from stator voltage equations. The proposed method is verified by simulation results comparing with conventional method.

• Journal of Magnetics
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• 제19권4호
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• pp.411-417
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• 2014

This paper presents the shape optimization of a permanent magnet synchronous motor to reduce the torque ripple and iron loss. Specifically, the harmonics of the electromotive force and cogging torque are decreased by adjusting the permanent magnet arrangement and non-uniform air gap length. In addition, an additional flux path along the q-axis is proposed with a unique rotor shape to increase the q-axis inductance and reluctance torque. The improvement in the performance of the proposed model is verified with simulated and experimental results.

• 전력전자학회논문지
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• 제8권3호
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• pp.211-220
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• 2003

본 논문은 직접 토오크 제어 (Direct Torque control, DTC)를 이용한 릴럭턴스 동기전동기 (Reluctance Synchronous Motor, RSM)의 최대 효율 제어에 관한 연구이다. 릴럭턴스 동기전동기의 등가모델 해석에 있어서 철손의 영향을 고려하여 이론적으로 분석하였으며, 최대효율제어를 위하여 토크 전류와 여자전류 사이의 최적 각을 유도하였다. 릴럭턴스 동기전동기의 경우는 자속이 전류에 비례하므로 유도전동기와는 달리 자속레벨을 제어하면서 토오크의 동특성을 유지할 수 있다는 특징을 가지고 있으며, 제시된 연구에서는 릴럭턴스 동기전동기의 이러한 특징을 적용하여 직접 토오크 제어의 장점인 빠른 토오크 응답특성을 유지하면서 최대 효율 제어가 이루어지도록 한다. d/q 릴럭턴스 비가 2.57인 1.0 Kw 릴럭턴스 동기전동기를 이용하여 실험을 통해 제안된 방법들의 정당성을 입증하였다.

• 전기학회논문지
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• 제63권3호
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• pp.349-357
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• 2014

The performance of a Synchronous Reluctance Motor (SynRM) in terms of torque and power factor depends on the two-axis inductances $L_d$ and $L_q$ of the machine. The Axially Laminated Anisotropic (ALA) rotor should be proposed in an effort to increase the $L_d/L_q$ ratio and the $L_d-L_q$ difference to secure high torque density and high power factor. So, ALA rotor is suitable for high speed instruments. This paper deals with optimum design of Axially Laminated Anisotropic Synchronous Reluctance Motor (ALA-SynRM) and comparison of characteristics with induction motor. Coupled Finite Element Methodology (FEM) & Response Surface Methodology (RSM) have been used to evaluate optimum design solutions. Comparisons are given with characteristics of a same rated wattage induction motor and those of ALA-SynRM respectively.

• 조명전기설비학회논문지
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• 제29권12호
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• pp.83-87
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• 2015

This paper presents a simple notch filter, which is so suitable for three-phase unbalanced and distorted power line. In the d-q synchronous transformation, three-phase unbalanced and distorted voltages generate lots of ripple voltages on d-q axes. The ripples make disturbances on controllers such as PLL of phase tracking. Unbalanced state makes ripple of double the frequency of power line. Odd harmonics 5th and 7th on the line make even 4th and 6th ripples on d-q axes due to the rotating reference frame, respectively. Cascaded two comb filters, delay lines 1/4T and 1/8T, are adopted for the ripple rejection. The filter rejects harmonics 2nd, 4th, 6th, 10th and so on. They are very effective to remove the ripples of both unbalance and distortion. The filter, implemented by two FIFOs on an experimental system, is adopted on a PLL controller of power line phase tracking. Through the simulation and experimental results, performance of the proposed comb filter has been validated.