Fault indicator

About: Fault indicator is a research topic. Over the lifetime, 10057 publications have been published within this topic receiving 143482 citations. The topic is also known as: FCI & power line fault indicator.

MODIFI: a MODel-implemented fault injection tool

Abstract: Fault injection is traditionally divided into simulation-based and physical techniques depending on whether faults are injected into hardware models, or into an actual physical system or prototype. Another classification is based on how fault injection mechanisms are implemented. Well known techniques are hardware-implemented fault injection (HIFI) and softwareimplemented fault injection (SWIFI). For safety analyses during model-based development, fault injection mechanisms can be added directly into models of hardware, models of software or models of systems. This approach is denoted by the authors as model-implemented fault injection. This paper presents the MODIFI (MODel-Implemented Fault Injection) tool. The tool is currently targeting behaviour models in Simulink. Fault models used by MODIFI are defined using XML according to a specific schema file and the fault injection algorithm uses the concept of minimal cut sets (MCS) generation. First, a user defined set of single faults are injected to see if the system is tolerant against single faults. Single faults leading to a failure, i.e. a safety requirement violation, are stored in a MCS list together with the corresponding counterexample. These faults are also removed from the fault space used for subsequent experiments. When all single faults have been injected, the effects of multiple faults are investigated, i.e. two or more faults are introduced at the same time. The complete list of MCS is finally used to automatically generate test cases for efficient fault injection on the target system.

Transmission-Line Fault Analysis Using Synchronized Sampling

Abstract: An automated analysis approach, which can automatically characterize fault and subsequent relay operation, is the focus of this paper. It utilizes synchronized samples captured during transients from both ends of the transmission line to detect, classify, and locate transmission-line faults and can verify that the tripped line has indeed experienced a fault. The proposed method is tested for several faults simulated on an IEEE 118-bus test system and it has been concluded that it can detect and classify a fault using prefault and postfault recorded samples within 7 ms of fault inception and can accurately locate a fault with 3% accuracy. This time response performance is highly desirable since with the increasing use of modern circuit breakers, which can open the faulty line in less than two cycles, the time window of the captured waveforms is significantly reduced due to the unavailability of measurement signals after breakers open.

A Novel UHV/EHV Transmission-Line Pilot Protection Based on Fault Component Integrated Impedance

Abstract: Based on the ratio of the sum of the fault component voltage phasors across the two terminals in the transmission line to the sum of the current phasors through the same line, which is defined as fault component integrated impedance in this paper, a new transmission-line pilot protection principle is proposed. When an external fault occurs, the amplitude of the fault component integrated impedance that reflects the capacitance impedance of the line becomes large; When an internal fault occurs, the amplitude of the fault component integrated impedance which reflects the impedance of the system source and the line, becomes relatively small. Therefore, the fault in the line can be detected according to this characteristic. The criterion is not affected by the current through the capacitance and is not affected by the fault resistance. It can be applied to the line with or without shunt reactor. Also, it can be easily set. Both the simulation results with Electromagnetic Transients Program and dynamic model data verify the validity of the proposed principle.

Detection, Classification, and Estimation of Fault Location on an Overhead Transmission Line Using S-transform and Neural Network

Abstract: This article demonstrates a technique for diagnosis of fault type and faulty phase on overhead transmission lines. A method for computation of fault location is also incorporated in this work. The proposed method is based on the multi-resolution S-transform, which is used for generating complex S-matrices of the current signals measured at the sending and receiving ends of the line. The peak magnitude of the absolute value of every S-matrix is noted. The phase angle corresponding to every peak component is obtained from the argument of the relevant S-matrix. These features are used as input vectors of a probabilistic neural network for fault detection and classification. Detection of faulty phase(s) is followed by estimation of fault location. The voltage signal of the affected phase is processed to generate the S-matrix. The frequency components of the S-matrices for different fault locations are used as input vectors for training a back-propagation neural network. The results are obtained with s...

An architecture for fault detection and isolation based on fuzzy methods

Abstract: Model-based fault detection and isolation (FDI) is an approach with increasing attention in the academic and industrial fields, due to economical and safety related matters. In FDI, the discrepancies between system outputs and model outputs are called residuals, and are used to detect and isolate faults. This paper proposes a model-based architecture for fault detection and isolation based on fuzzy methods. Fuzzy modeling is used to derive nonlinear models for the process running in normal operation and for each fault. When a fault occurs, fault detection is performed using the residuals. Then, the faulty fuzzy models are used to isolate a fault. The FDI architecture proposed in this paper uses a fuzzy decision making approach to isolate faults, which is based on the analysis of the residuals. Fuzzy decision factors are derived to isolate faults. An industrial valve simulator is used to obtain several abrupt and incipient faults, which are some of the possible faults in the real system. The proposed fuzzy FDI architecture was able to detect and isolate the simulated abrupt and incipient faults.