• 마이크로전자및패키징학회지
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• 제23권4호
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• pp.49-55
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• 2016

Nowadays there are magnetic sensors in a wide variety of equipment such as computers, cars, airplanes, medical and industrial instruments. In many of these applications the magnetic sensors offer safe and non-invasive means of detection and are more reliable than other technologies. The electric current in a conductor generates a magnetic field detected by this type of sensor. This work aims to define a package dedicated to an electrical current sensor using a MTJ (Magnetic Tunnel Junction) as a sensing device. Four different proposals of packaging, three variations of the chip on board (CoB) package type and one variation of the thin small outline package (TSOP) were analyzed by COMSOL modeling software by simulating a brad range of current injection. The results obtained from the thermal and magnetic analysis has proven to be very important for package improvements, specially for heat dissipation performance.

• Journal of Electrical Engineering and information Science
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• 제2권4호
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• pp.86-91
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• 1997

A method of detecting the three phase currents for a voltage-fed pusle width modulated(PWM) inverter is proposed, where only one current sensor is utilized on the dc-link. The proposed method has the constant sampling time by employing he modified space-vector PWM technique which generates the rearranged switching pattern to detect a phase current from ad dc-link current. Experimental results show that eh proposed scheme provides a very good detection method of three phase currents without phase current sensors. This method is very simple and has small detection errors.

• 센서학회지
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• 제19권6호
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• pp.475-482
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• 2010

Rogowski coil which detects magnetic flux on current changes. It is used for digital integration with watt-hour meter's current sensor, because, Rogowski coil has non-cored or non-magnetic core structure, so that, it cannot be saturated magnetically. This is a study for inventing accurate electric current sensors that have been applied on multi-layer ceramic substrate. We have confirmed its properties from each different layer's materials and pattern sizes by MWS 3D Electromagnetic field analysis program. And, after sensor manufacturing on multi-layer ceramic substrate, we confirmed its sensing quality is reliable as accurate electric current sensor for watt-hour meter.

• Journal of Power Electronics
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• 제18권1호
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• pp.1-10
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• 2018

Recently, the nine-switch inverter has been proposed as a dual output inverter. To date, studies on the control strategies for NSIs have been mostly combined with their application. However, in this paper, a mathematical model and control strategy for nine-switch inverters has been proposed in view of the topology. A switching function model and equivalent circuit model of a nine-switch inverter have been built in ${\alpha}{\beta}$ coordinates. Then, a novel current observer with an improved integrator is proposed based on the switching function model, and a direct power control strategy is proposed. No current sensors are used in the proposed strategy, and only two voltage sensors are employed. The performance of the proposed control method is verified by simulation and experimental results.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.278-281
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• 2000

In this abstract a novel control scheme of voltage-source PWM rectifiers using only dc-side sensors is proposed. The phase currents are reconstructed from switching states of the rectifier and the dc output current. For effective current control the currents are estimated by a predictive state observer. Also both the phase angle and the magnitude of th source voltage are estimated by phase estimator and magnitude estimator respectively. The validity of the proposed ac sensorless technique is verified by experimental results.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.749-752
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• 1999

A new interface circuit for variable resistive sensors is proposed. The interface circuit compose of only two strain gages, a voltage-to-current converter, and current mirror with two outputs. A new dual slope A/D converter based on linear operational transconductance amplifier for the testing of prototype interface circuit is also described. The theory of operation is presented and experimental results are used to verify the theoretical predictions. The results show close agreement between predicted behaviour and experimental performance.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.633-634
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• 2006

A new specification-based analog and mixed-signal test technique using high performance current sensors is proposed. The proposed technique using current sensors built in external ATE has little hardware overhead in circuit under test and high testability without time consuming operation of test point placement algorithm.

• 한국전자파학회논문지
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• 제28권12호
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• pp.993-998
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• 2017

본 논문에서는 공장에서 많이 사용하는 삼상 배전반에서 자기센서를 이용한 고정밀 전류를 측정하기 위한 기법을 제안하고 이를 분석 및 검증한 결과를 서술하였다. 일반적으로 개방형 자기센서 기반의 비접촉식 방식으로 전류를 측정할 경우 인접한 전선의 전류에서 유도되는 자기장의 영향으로 그 오차가 10 % 이상으로 증가되는 단점을 가지고 있으며, 이로 인하여 대부분의 상용 전류센서의 경우 투자율이 큰 ferrite를 이용한 루프형 구조를 채택하고 있다. 제안된 고정밀 전류센싱 기법은 인접한 자기장의 크기를 측정하여 이를 수학적으로 제거함으로써 고정밀의 전류센서를 개방형 자기센서를 사용하여 구현 가능할 수 있으며, 전류센서의 단가 및 사이즈를 줄일 수 있어 공장 내의 다양한 하위 노드 단에서 소모되는 전류를 측정 가능한 장점을 가지고 있다.

• 터널과지하공간
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• 제33권6호
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• pp.534-546
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• 2023

디스크 커터는 과다하게 마모되거나 손상되는 경우 회전이 불가능하거나 효율적으로 암석을 절삭하는 것이 불가능하다. 따라서 디스크 커터의 마모정도에 따라 교체주기를 적절하게 관리하는 것이 매우 중요하다. 일반적으로 디스크 커터의 교체주기를 결정하기 위해서 인력에 의한 정기적인 계측을 수행한다. 이러한 인력에 의한 디스크 커터의 계측은 작업자의 안전과 관련한 이슈가 있고, 부정확한 계측결과를 가져올 수도 있다. 이러한 이유로 해외에서는 디스크 커터의 마모정도를 센서를 통해 실시간으로 측정하기 위한 기술의 개발이 이루어지고 있으며, 디스크 커터의 마모량 계측에는 초음파 센서, 와전류 센서, 자기 센서 등이 활용된다. 본 연구에서는 TBM 디스크 커터의 마모량을 실시간으로 계측하기 위한 와전류 센서의 적용성을 평가하였다. 와전류 센서의 거리 계측정확도를 실험실 모사시험을 통해 평가하였고, 특히 디스크 커터가 노출될 수 있는 챔버 내 여러 환경조건에서의 계측정확도를 비교하였다. 최종적으로는 17인치 디스크 커터를 활용하여 와전류 센서의 계측 정확도를 검증하였다.

• 한국의류산업학회지
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• 제21권6호
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• pp.697-707
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• 2019

This review paper deals with materials, classification, and a current article investigation on smart textile sensors for wearable vital signs monitoring (WVSM). Smart textile sensors can lose electrical conductivity during vital signs monitoring when applying them to clothing. Because they should have to endure severe conditions (bending, folding, and distortion) when wearing. Imparting electrical conductivity for application is a critical consideration when manufacturing smart textile sensors. Smart textile sensors fabricate by utilizing electro-conductive materials such as metals, allotrope of carbon, and intrinsically conductive polymers (ICPs). It classifies as performance level, fabric structure, intrinsic/extrinsic modification, and sensing mechanism. The classification of smart textile sensors by sensing mechanism includes pressure/force sensors, strain sensors, electrodes, optical sensors, biosensors, and temperature/humidity sensors. In the previous study, pressure/force sensors perform well despite the small capacitance changes of 1-2 pF. Strain sensors work reliably at 1 ㏀/cm or lower. Electrodes require an electrical resistance of less than 10 Ω/cm. Optical sensors using plastic optical fibers (POF) coupled with light sources need light in-coupling efficiency values that are over 40%. Biosensors can quantify by wicking rate and/or colorimetry as the reactivity between the bioreceptor and transducer. Temperature/humidity sensors require actuating triggers that show the flap opening of shape memory polymer or with a color-changing time of thermochromic pigment lower than 17 seconds.