• 전기학회논문지
• /
• 제60권4호
• /
• pp.805-810
• /
• 2011

This paper deals with the method and algorithm used to find fault locations in gas insulated transmission line. The method uses UHF sensors and digital oscilloscope to detect discharge signals emitted to the outside through insulating spacer in the event of breakdown inside GIL. UHF sensors are the external type and installed at outside of insulating spacers of GIL. And we used wavelet signal processing to analyze the discharge signals and confirm the exact fault location findings in the GIL test line. This method can overcome demerit of TDR(Time Domain Reflectometer) method having been applied to detect fault location for conventional underground transmission lines, and Ground Fault Sensors used in conventional GIS systems. TDR method requires high level of specialty and experience in analyzing the measured signals. Ground fault sensors are installed inside GIL and can be destroyed by high transient voltage. This paper's method can simplify the fault location process and minimize the damage of sensors. In addition, this method can estimate the fault location only by the time difference when discharge signals are arrived to detecting sensors at the ends of GIL sections without reasons of breakdown. To test the performance of our method, we installed sensors at the ends of test line of GIL(84m) and sensed discharge signals occurred in GIL, energized with AC voltage generator up to 700kV.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
• /
• pp.547-550
• /
• 2004

Superconducting fault current limiter(SFCL) is expected to be introduced into electric power system in future as an effective countermeasure for the increase of the short-circuit current due to the growth of the electric power system. SFCL has a merit that the fault current can be limited by the resistance generated when a superconductor transits from a superconducting state to a normal state without additional detecting device. In this paper, we investigated the resistance variance of resistive type SFCL and the fault current limiting characteristics due to the amplitude of source voltage. We could obtain the more effective fault current limiting characteristics of SFCL as the source voltage increased.

• 전기전자학회논문지
• /
• 제25권2호
• /
• pp.330-336
• /
• 2021

하드웨어 이중화 구성 수를 줄이는 대표적인 방법은 마이크로컨트롤러로 고장을 검출, 식별 및 수용을 위한 해석적 기법으로 구현하는 것이다. 본 논문에서는 해석적 기법 중 하나인 고장 검출 필터를 항공기 터보팬 엔진 시스템에 적용하였다. 고장 검출 필터는 특수한 형태의 관측기로써 특정한 고장 발생시 잔차가 출력 공간에서 일정한 방향을 유지함으로써 고장의 위치 판별이 가능한 장점이 있다. 이에 본 논문에서는 터보팬 엔진 내 공기 터빈 시스템의 단일 입출력 동적 시스템 모델링, 고장 검출 필터 설계 및 이를 적용한 모의실험 결과를 나타내었다. 모의실험 결과를 통해 고장 검출 필터가 갖는 방향성에 대한 민감성 효과로 고장 검출이 유효하게 적용될 수 있음을 보였다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 하계학술대회 논문집 C
• /
• pp.1133-1135
• /
• 1999

In this paper we propose to develop program witch can improve the detecting capability of impedance fault in power transmission system. It is difficult to setting relay because the different type relays have many setting values to coordinate with each other. The proposed program assist a user in setting relay with convenience grapic environment and database.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 하계학술대회 논문집 D
• /
• pp.1000-1002
• /
• 1997

In this paper we proposes a scheme which can improve the detecting capability of the high impedance fault of the conventional distance relaying. It utilizes the directional ground overcurrent relay called HIFR together with the distance relay in order to secure the security and selectivity.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2008년도 추계학술대회 논문집
• /
• pp.202-207
• /
• 2008

This study provides review and improvement plans for the possible problems caused when the CV cable is used as a positive feeder line which supplies power from the DC HSCB (high-speed circuit breaker) to the catenariesin Seoul Metro which is using direct-current feeder method. In detail, this study contributes to stabilizing the power line by triggering a protective device by instantly detecting potential rise which happens when grounding fault occurs in non-grounding type CV cable shield.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
• /
• pp.556-558
• /
• 2004

In this paper, we introduce a new method of detecting faults for a power converter unit in Control Rod Control System. The faults of a power converter unit can exert harmful influence upon the operation of Control Rod Drive Mechanisms and the control of the reactor output. This situation makes the quick and correct detection of failures in a power converter unit very important. We devise a new method of fault detection for the digital power controller and improve the drawbacks of the existing fault detector.

• 대한전자공학회논문지
• /
• 제17권4호
• /
• pp.31-37
• /
• 1980

본 논문은 조합논리회로의 고장검출에 관한 것이다. 회로내의 각 line의 test set사이의 관계를 고찰하므로서 모든 test set을 D-algorithm을 반복하여 적용하지 않고 어느 하나의 test set 만을 구하여 이를 전파시켜서 구할 수 있는 방법을 연구하였고, 두번째로는 모든 선마다의 test set을 구하여 이를 회로에 모두 인가하여 고장을 검출하는 종래의 방법을 벗어나서 입력수만큼의 test set을 인가하여 출력의 상고를 점검하여 고장을 검출하는 방법을 제시되었다.

• Journal of Electrical Engineering and Technology
• /
• 제10권6호
• /
• pp.2393-2405
• /
• 2015

This paper considers a decentralized multiple faults detection and isolation (FDI) scheme for reconfigurable manipulators. Inspired by their modularization property, a global sliding mode (GSM) based stable adaptive fuzzy decentralized controller is investigated for the system in fault free, while for the system suffering from multiple faults (actuator fault and sensor fault), the decentralized sliding mode observer (DSMO) is employed to detect their occurrence. Hereafter, the time and location of faults can be determined by a fault isolation scheme via a bank of DSMOs. Finally, the effectiveness of the proposed schemes in controlling, detecting and isolating faults is illustrated by the simulations of two 3-DOF reconfigurable manipulators with different configurations successfully.

• 한국항행학회논문지
• /
• 제13권1호
• /
• pp.74-78
• /
• 2009

본 논문은 IP-USN 기반의 FDA(Fault Detection Agent)의 설계와 구축을 설명한다. FDA는 IP-USN 기반의 홈 네트워크 환경에서 멀티미디어 원격 교육을 위한 소프트웨어 오류를 감지하기에 적합한 에이전트이다. 이 시스템은 ED, ES로 구성되어 있다. ED는 IP-USN 기반 환경에서 멀티미디어 원격 교육을 위하여 훅킹 기법으로 오류를 감지하는 에이전트이다. ES는 IP-USN 기반 환경에서 멀티미디어 원격 교육을 위하여 오류를 공유하는 에이전트이다.