• 전기전자학회논문지
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• 제24권4호
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• pp.1129-1135
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• 2020

배터리를 사용함에 따라 노화가 진행되면 배터리의 충전 가능 용량을 나타내는 State of Health(SoH)가 줄어들게 된다. 배터리 모니터링 시스템(BMS)에서 SoH를 추정하는 것이 매우 중요하며, 이를 위해 배터리 내부 저항을 측정하는 방법이 많이 사용된다. 일반적으로 배터리에 특정한 주파수의 전류원을 인가하고 전압응답을 측정하여 내부저항을 연산한다. 충전기가 동작할 경우 전압응답에 충전 고조파 잡음이 발생하여 저항 측정의 정확도가 떨어진다. 본 논문에서는 충전잡음의 영향을 제거하기 위하여 강인한 배터리 내부저항 측정 알고리즘을 제안하였다. 전류원 신호와 전압응답 신호를 일정한 주기 동안 적분하여 잡음을 제거하는 방법으로 우수한 정확도와 안정된 연산결과를 보였다. 무정전 전원장치용 BMS에 적용하여 제안한 방법의 유용함을 입증하였다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.823-824
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• 2016

일반적으로 배전반, 분전반, 전동기제어반(Motor Control Center;MCC)은 집단거주지역, 빌딩, 학교, 공장, 항만, 공항, 상하수 처리장, 변전소, 중공업 플랜트 등의 광범위한 전력 수용가에 설치되어 특고압의 전력을 해당 설비들에 요구되는 전압으로 변환하여 공급하는데 사용된다. 이와 같은 배전반, 분전반, MCC에 포함되는 전기설비의 사고는 부스바 접속부의 열화에 의한 사고, 부스바의 접점 및 연결 부위에서의 접촉 불량에 의한 사고, 부스바 접속부의 과열 현상에 의한 사고로 구분된다. 본 논문에서는 부스바 접촉부의 볼트 및 너트의 풀림상태, 접촉부 열화 측정이 가능하며, 배전반 내부온도와 부스바 온도를 측정하여 추이변화에 대한 감시기능이 있는 부스바 접촉부 체결상태 모니터링 시스템을 제안한다. 제안된 시스템은 정량적인 부스바 체결상태 검출과 부스바 현재온도 검출의 이중적인 센싱에 의해 부스바 접촉부 정상여부 판별이 가능하여 전기설비 사고를 줄일 수 있을 것으로 기대된다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 전력전자학술대회 논문집
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• pp.143-148
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• 1998

A dynamic electrical parameter monitoring device was designed to simultaneously record the instantaneous value of voltage, current, power, and resistance during spot welding. The data obtained using this technique have been analyzed in term of the relationships of these parameters to the phenomena occuring during the formation(surface break-down, nugget formation and mechanical collapse) of spot weld. Finally, a database implementation is undertaken to develop techniques for improving weld quality of the resistance spot welder.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2004년도 추계학술발표대회 개요집
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• pp.196-198
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• 2004

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2003년도 추계학술발표대회 개요집
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• pp.132-134
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• 2003

• Journal of Welding and Joining
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• 제18권2호
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• pp.239-239
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• 2000

Automobile manufacturers have employed resistance spot welding(RSW) to join steel sheets for structural rigidity o automobile body. Driven by the need to reduce weight and fuel consumption, car companies have been evaluating aluminum intensive vehicles(AIVs) as a way to reduce vehicle weight without downsizing. During the transition from all steel-construction vehicle body to aluminum intensive body, joining aluminum to steel sheets emerges as a serious contender in automobile body. This paper deals with application of transition material to RSW aluminum to steel. Placing transition material insert between the aluminum/steel interface was found very effective to overcome incompatibility between aluminum and steel. Use of transition insert allows for two separate weld muggets to be formed in their respective aluminum/ aluminum and steel/ steel interfaces. This RSW process was monitored with the aid of dynamic resistance sampling. Typical patterns in sampled dynamic resistance curves indicated formation of sound nugget. (Received February 28, 2000)

• Journal of Welding and Joining
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• 제18권2호
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• pp.112-118
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• 2000

Automobile manufacturers have employed resistance spot welding(RSW) to join steel sheets for structural rigidity of automobile body. Driven by the need to reduce weight and fuel consumption, car companies have been evaluating aluminum intensive vehicles(AIVs) as a way to reduce vehicle weight without downsizing. During the transition from all steel-construction vehicle body to aluminum intensive body, joining aluminum to steel sheets emerges as a serious contender in automobile body. This paper deals with application of transition material to RSW aluminum to steel. Placing transition material insert between the aluminum/steel interface was found very effective to overcome incompatibility between aluminum and steel. Use of transition insert allows for two separate weld nuggets to be formal in their respective aluminum/aluminum and steel/steel interfaces. This RSW process was monitored with the aid of dynamic resistance sampling. Typical patterns in sampled dynamic resistance curves indicated formation of sound nugget.

• Advanced Composite Materials
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• 제16권2호
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• pp.135-149
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• 2007

In the automobile industry, structural health monitoring of fiber reinforced polymer composite parts is a widespread need for maintenance before breakdown of the functional elements or a complete vehicle. High performance sensors are generally used in many of the structural health monitoring operations. Within this study, a carbon fiber sewing thread has been used as a low cost laminate failure sensing element. The experimentation plan was set up according to the electrical conductance and flexibility of carbon fiber threads, advantages of preforming operations, and sewing mechanisms. The influence of the single thread damages by changing the electrical resistance and monitoring the impact location by using carbon thread sensors has been performed. Innovative utilization of relatively cost-effective carbon threads for monitoring the delamination of metallic inserts from the basic composite laminate structure is a highlighting feature of this study.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1999년도 특별강연 및 추계학술발표대회 개요집
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• pp.142-145
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• 1999

The dynamic resistance monitoring is one of the important issues in that in-process and real time quality assurance of resistance spot weld is needed to increase the product reliability. Secondary dynamic resistance patterns, as a real manner, are hard to adapt those factors in real time and in-plant system. In the present study, a new dynamic resistance detecting method is presented as a practical manner of weld quality assurance at the primary circuit. By the correlation analysis, it is found that the primary dynamic resistance patterns are basically similar to those of the secondary. Various dynamic resistance indices are characterized with the primary curve. And quality of the weld, like the tensile shear strength, is estimated using adaptive neuro-fuzzy estimation system which is consisted of the Sugeno fuzzy algorithm. Through the fuzzy clustering and parameter optimization, real time weld quality assurance system with less efforts is proposed.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.330-335
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• 2002

Resistance spot welding is one of the most widely used processes in sheet metal fabrication. Quality assurance of welding has been important to increase the productivity. In this study, weld quality estimation using primary circuit dynamic resistance applied to the in-process real-time systems. For quality estimation, factors relating to quality were extracted from the dynamic resistance, measured in the timer. The relationship between these factors and weld quality was determined through a artificial neural network model. This method has the advantage over the conventional one, such as obtaining the quality information without the use of extra devices.