• 제목/요약/키워드: Fault-Tolerant System

검색결과 422건 처리시간 0.026초

철도신호의 Fail Safe/Fault Tolerant 시스템에 대한 검증방법에 대한 연구 (A Study On Verification Methodology On Railway Signalling System related to Fail Safe/ Fault Tolerant)

  • 이종우;정의진;황종규;신덕호
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2002년도 하계학술대회 논문집 B
    • /
    • pp.1214-1219
    • /
    • 2002
  • Railway signalling system always is required high safety and reliability. The failure of the train control system can provoke a serious accident. In this paper, we show how to achieve the safety and reliability by dividing signalling system into vital and non functions, studying operational environment.

  • PDF

3상 PWM 정류기의 스위치 개방 고장 감지 및 허용운전 방법 (Switch Open Fault Detection and Tolerant Operation Method for Three Phase PWM Rectifier)

  • 신희근;안병웅;김학원;조관열;정신명
    • 전력전자학회논문지
    • /
    • 제17권3호
    • /
    • pp.266-273
    • /
    • 2012
  • In this paper, the new open fault detection and tolerant operation method for 3 phase PWM rectifier is proposed. When open fault occurred on the inverter switches of 3 Phase PWM rectifier, the DC link voltage ripple is increased because the input current of the faulty phase is distorted. In this case, the quality of electric power would decrease, and the life time of DC link capacitor is decreased. The open fault is detected by a simple MRAS(Model Reference Adaptive System) without additional hardware sensors, and the tolerant operation carried out by turning on the opposite switch of the faulty switch without any redundancy. By the proposed method, the faulty phase input current can be controlled, so that 3-phase input current is balanced relatively under the faulty condition and the voltage ripple of DC link output is reduced. The validity of the proposed technique is proved on the 6kW 3-phase PWM rectifier system by simulation and experiment.

Performance Evaluation of the Field-Oriented Control of Star-Connected 3-Phase Induction Motor Drives under Stator Winding Open-Circuit Faults

  • Jannati, Mohammad;Idris, Nik Rumzi Nik;Aziz, Mohd Junaidi Abdul
    • Journal of Power Electronics
    • /
    • 제16권3호
    • /
    • pp.982-993
    • /
    • 2016
  • A method for the fault-tolerant vector control of star-connected 3-phase Induction Motor (IM) drive systems based on Field-Oriented Control (FOC) is proposed in this paper. This method enables the control of a 3-phase IM in the presence of an open-phase failure in one of its phases without the need for control structure changes to the conventional FOC algorithm. The proposed drive system significantly reduces the speed and torque pulsations caused by an open-phase fault in the stator windings. The performance of the proposed method was verified using MATLAB (M-File) simulation as well experimental tests on a 1.5kW 3-phase IM drive system. This paper experimentally compares the operation of the proposed fault-tolerant vector controller and a conventional vector controller during open-phase fault.

신경회로망을 이용한 항공기 센서 및 구동장치 고장보완 제어시스템 설계에 관한 연구 (A Study on the Fault Tolerant Control System for Aircraft Sensor and Actuator Failures via Neural Networks)

  • 송용규
    • 한국항행학회논문지
    • /
    • 제7권2호
    • /
    • pp.171-179
    • /
    • 2003
  • 본 논문에서는 항공기 센서와 구동장치 고장시 신경회로망을 이용하여 이를 대처하는 고장보완시스템에 대해서 고려한다. 센서 고장의 경우에는 비행동역학적 관계식을 적절히 이용하여 신경회로망으로 센서고장을 진단/규명하고 고장난 센서를 대체할 수 있는 시스템을 설계하고 또한 구동장치의 고장이나 조종면의 일부 파손시 이를 진단/규명하고 보완하여 새로운 트림상태로 안정화시키는 제어시스템을 제안한다. 설계된 두 보완시스템을 하나의 가격함수로 통합하여 운용하는 알고리즘을 제안하며 이의 검증을 위해 센서와 구동장치의 고장을 가상적으로 설정하여 시뮬레이션함으로써 보완시스템의 성능을 확인한다.

  • PDF

원자력 발전소 디지털 원자로 보호시스템의 설계에 대한 안전성 평가 (Safety Assessment for the Design of Digital Reactor Protection System of Nuclear Power Plant)

  • 공명복;이상용
    • 산업공학
    • /
    • 제23권1호
    • /
    • pp.68-77
    • /
    • 2010
  • Digital reactor protection system which consists of many identical modules, is fault- tolerant to provide high safety. The modules themselves including DSP(digital signal processing) card are also fault-tolerant in nature. This paper assesses the safety for being-designed digital reactor protection system of 2-out-of-4 G structure with lockout. Some interesting design alternatives are compared. Fault tree analysis for assessing system safety is performed by Relex software. The selected reactor protection system fully satisfies EPRIURD stipulation of mean failure time of 50 years.

Multi-Agent System for Fault Tolerance in Wireless Sensor Networks

  • Lee, HwaMin;Min, Se Dong;Choi, Min-Hyung;Lee, DaeWon
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제10권3호
    • /
    • pp.1321-1332
    • /
    • 2016
  • Wireless sensor networks (WSN) are self-organized networks that typically consist of thousands of low-cost, low-powered sensor nodes. The reliability and availability of WSNs can be affected by faults, including those from radio interference, battery exhaustion, hardware and software failures, communication link errors, malicious attacks, and so on. Thus, we propose a novel multi-agent fault tolerant system for wireless sensor networks. Since a major requirement of WSNs is to reduce energy consumption, we use multi-agent and mobile agent configurations to manage WSNs that provide energy-efficient services. Mobile agent architecture have inherent advantages in that they provide energy awareness, scalability, reliability, and extensibility. Our multi-agent system consists of a resource manager, a fault tolerance manager and a load balancing manager, and we also propose fault-tolerant protocols that use multi-agent and mobile agent setups.

Fault Tolerant Control Methods for Dual Type Independent Multi-Phase BLDC Motor under the Open-Switch Fault Conditions

  • Kim, Yong-Hyu;Heo, Hong-Jun;Park, June-Ho;Kim, Jang-Mok
    • Journal of Electrical Engineering and Technology
    • /
    • 제13권2호
    • /
    • pp.722-732
    • /
    • 2018
  • Dual type Independent multi-phase BLDC Motor (DI-BLDCM) is designed to be robust to faulty conditions of motor and drive system. Despite the efforts of the motor design, open-switch faults of DI-BLDCM drive system cause the torque ripple of the motor. This torque ripple makes unwanted sound noise and mechanical vibration of associated systems. This paper proposes four methods for compensating the torque ripple and compares the characteristics of each proposed method. All proposed methods are able to reduce the torque ripple to similar level of the healthy condition, although the motor operates in open-switch fault conditions. However, these methods have different characteristics in various fault conditions. Therefore, from the results of the comparison, the suitable method is selected for the various fault conditions. The feasibility of the proposed methods is proved by the several experimental results.

FTCS (Fault Tolerant Control System)의 개발에 관한 연구 (A study on the development of a fault tolerant control system)

  • 문봉채;조영조;김지홍;변증남
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
    • /
    • pp.161-163
    • /
    • 1987
  • An FTCS is developed for the purpose of improving the reliability of a process control system. The proposed FTCS has capabilities of failure detection, back-up control, graphic display, and self-checking. Also the FTCS is combined with the process simulator to experiment in laboratory for the evaluation of performance of operation. The FTCS is applied to Thermal Power Plant .

  • PDF

다중 제어면 고장에 대한 제어면 재분배 고장 대처 기법 (Fault-Tolerant Networked Control Systems Using Control Allocation for Failures in Multiple Control Surfaces)

  • 양인석;김동길;이동익
    • 제어로봇시스템학회논문지
    • /
    • 제17권11호
    • /
    • pp.1067-1073
    • /
    • 2011
  • In this paper, the methodology of a CA (Control Allocation) based FTNCS (Fault-Tolerant Networked Control System) is proposed. Control allocation is a control surface management technique by redistributing the redundant control surfaces in overactuated systems. In modern high performance aircrafts, they adopt many redundant control surfaces to provide high performance and to satisfy various tactical requirements. Moreover, redundant control surfaces provide an opportunity to compensate performance degradation due to failures in more than one actuator by re-allocating redundant control surfaces. Simulation results with an F-18 HARV demonstrate that the proposed CA based FTNCS can achieve a fast and accurate tracking performance even in the presence of actuator faults.

T-S 퍼지 시스템을 위한 관측기 기반 고장포용 제어기 설계 (Observer-based Fault Tolerant Controller Design for T-S Fuzzy Systems)

  • 지성철;이호재;김도완
    • 제어로봇시스템학회논문지
    • /
    • 제17권11호
    • /
    • pp.1154-1158
    • /
    • 2011
  • In this paper, we discuss an observer-based fault tolerant controller design for the T-S (Takagi-Sugeno) fuzzy system with exogenous disturbance. To derive robust controller design conditions, we use $H_{\infty}$ design technique. The design conditions are derived in terms of linear matrix inequalities. An illustrative example is provided to show the effectiveness of the proposed methodology.