• Journal of Electrical Engineering and Technology
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• 제2권2호
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• pp.280-285
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• 2007

This paper presents a robustly adaptive flux observer for speed-sensorless induction motor control. The proposed approach employs additional robustifying signals to cope with the parametric uncertainties instead of designing an estimator, which has been normally used in power electronic drives. For that, the sliding-mode like adaptive controls are designed and their gain parameters are determined so that the observer dynamics are stable in the sense of Lyapunov, and furthermore they can guarantee the robustness against parametric uncertainties in induction motor systems. Estimated rotor speed is to be used to generate feedback control signal for the speed sensorless vector control system. To show the validity and efficiency of the proposed system, simulation results are presented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.280-282
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• 2004

본 논문에서는 고조파 저감을 위해 사용하는 수동필터를 부하의 운전조건에 따라 자동으로 $개\cdot폐$할 수 있는 DSP 기반의 제어시스템을 개발하였다. 수동필터 제어시스템은 부하에서 발생하는 전압, 전류, 고조파, 무효전력, 역률 등을 측정 및 감시하여 수동필터 $개\cdot폐$ 장치에 신호를 보내어 부하의 운전조건에 따라 필터의 각 분로를 자동으로 $개\cdot폐$하게된다. 이러한 제어시스템은 100마력 직류전동기 구동장치를 사용하는 계통에 수동필터와 함께 설치하고 고조파 및 무효전력등을 측정함으로써 성능을 입증하였다.

• Journal of Power Electronics
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• 제11권3호
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• pp.294-303
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• 2011

In this paper an effective five-phase induction motor (IM) and its drive methods are proposed. Due to the additional degrees of freedom, the five-phase IM drive presents unique characteristics for enhancing the torque producing capability of the motor. Also the five-phase motor drives possess many other advantages when compared to traditional three-phase motor drives. Some of these advantages include, reducing the amplitude and increasing the frequency of the torque pulsation, reducing the amplitude of the current without increasing the voltage per phase and increasing the reliability. In order to maximize the torque per ampere, the proposed motor has concentrated winding, the produced back electromotive force (EMF) is almost trapezoidal, and the motor is supplied with the combined sinusoidal plus the third harmonic of the currents. For demonstrating the superior performance of the proposed five-phase IM, the motors are also analyzed on the synchronously rotating reference frame. To supply trapezoidal current waveform and to exclude the effect of the $3^{rd}$ harmonic current, a new control stratagem is proposed. The proposed control method is based on direct torque control (DTC) and rotor flux oriented control (RFOC) of the five-phase IM drives. It is able to reduce the acoustical noise, the torque, the flux, the current, and the speed pulsations during the steady state. The DTC transient merits are preserved, while a better quality steady-state performance is produced in the five phase motor drive for a wide speed range. Experimental results clearly demonstrated a more dynamic steady state performance with the proposed control system.

• 한국산학기술학회논문지
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• 제20권1호
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• pp.1-8
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• 2019

대부분의 회전자 저항 추정기는 표준모델(CQDM)과 대안모델(AQDM)을 활용한다. 두가지 모델에 기반한 회전자 저항 추정기들은 자속이 일정한 FOC와 같은 제어 환경에서는 정확한 회전자 저항 추정치를 제공하는 것으로 확인되었다. 반면, 단위전류당최대토크 (MTPA) 제어기와 같이 자속이 변화하는 동작환경에서는, AQDM에 기반한 회전자 저항 추정기가 다른 동작 운전점에서도 실제 회전자 저항을 정확하게 추정함을 보여주었다. 하지만, 자속이 변화하는 동작환경에서의 CQDM애 기반 회전자 저항 추정기의 성능은 검토된 적이 없으며 그의 성능은 의문이다. 따라서, 본 연구에서는 자속이 많이 변화하는 MTPA 제어기 기반 유도전동기 드라이브에서 CQDM에 기반한 회전자 저항 추정기의 성능을 검토하였으며 AQDM에 기반한 추정기와 비교하였다. AQDM에 기반한 추정기와는 달리, CQDM에 기반한 추정기는 실제 저항치보다 낮게 추정할 뿐만 아니라 여러 운전조건변화시마다 추정한 값에서 실제 존재할 수 없는 급격한 굴곡이 존재함을 실험 결과에서 확인하였다.

• 센서학회지
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• 제26권1호
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• pp.35-38
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• 2017

A thermally responsive hydrogel has reversibility with temperature during swelling. Here, we proposed origami inspired temperature sensor by using multi-layered hydrogel film. The formation of patterned stripes on microscale film drives bending to an angle that can be controlled linearly. Although temperature range was not wide, measured sensitivity of sensors has high resolution and accuracy. It providing a powerful platform for the design of sensitive sensors and that easily adapt other type of sensors in microscale.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 학술대회 논문집 전문대학교육위원
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• pp.131-135
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• 2006

In this paper, a new estimation algorithm for the rotor speed for SRM drives is described. The algorithm is implemented by the binary observer. The stability and robustness of the binary observer for the parameter variations of the SRM are Proved by variable structure control theory. Variable speed control of the SRM is accomplished by the estimated speed. Experiment results verify that the MRAS observer is able to estimate the speed.

• 전기의세계
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• 제18권6호
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• pp.46-52
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• 1969

An analysis of the torque characteristics is to be expected of a twin stator induction machine with 2nd excitation is made. A twin stator induction machine has, through common rotor, 2nd excitating action one set to another relatively, but there are not its effect on the torque characteristics. However, by combination with the external fixed or simpled 2nd excitating e.m.f., variable torque-speed drives can be effectively achieved.

• 전기의세계
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• 제30권7호
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• pp.454-459
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• 1981

The aim of study in this paper is that in a system drive of the converter-inverter fed induction motor, the minimum input power can be maintained by control the voltage and frequency of the motor. In theoretical and experiment results describtion motor efficiency is improved by properly varying the ratio v/f. At lightly load condition, for example its efficiency was improved from 44% to 66% as the ratio of v/f varied from 1 to 0.57.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.27-28
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• 2011

본 논문에서는 싱글전류센서를 이용하여 브러시리스 직류 전동기의 속도제어시스템 시뮬레이션 방법 및 그 결과을 제시한다. BLDC 전동기 제어에 매우 중요한 역할을 가지고 있는 피드백 센서 방식으로 싱글 전류검출센서를 이용한 속도제어 방법은 모터 설계의 비용을 낮추고, 심플한 제어기 설계를 가능하게 한다. 또한, 전동기에 손상을 줄 수 있는 오류조건을 감지함으로서 신뢰성을 향상시켜 줄 수 있다. 시뮬레이션에 사용하는 BLDC 전동기는 3상 Y결선 전동기를 모델로 하며 MATLAB/SIMULINK를 사용한 시뮬레이션을 수행하여 그 성능을 분석하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.101-103
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• 2004

The single phase switched reluctance motor has many merits in practical use because it has simple operating drives and control systems, very high energy density per unit volume comparing with three phase SRM. But it has also problems which is a starting device and torque ripple. One of the major problems is torque ripple which causes increased undesirable acoustic noise and possibly speed ripple. This paper describes an approach to determine optimum magnetic circuit parameters to minimize the torque ripple.