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.

Model-Based General Arcing Fault Detection in Medium-Voltage Distribution Lines

Abstract: Arcing fault is a special fault in medium-voltage distribution lines which can potentially cause shock hazard, apparatuses failure, and wild fire. Due to its short duration or low fault current, the detection of an arcing fault in distribution lines is highly challenging. In this paper, a model-based general detection method to separate an arcing fault from common nonarcing disturbances is proposed. First, an arcing fault model and a nonarcing disturbance model relating the disturbance characteristics, the load parameters, and the substation voltage and current waveforms are derived. For the accuracy of the models, the voltage drop on the distribution line is taken into consideration. Then, the procedure of arcing fault detection is introduced, including disturbance current calculation, parameters estimation, mean-square-error calculation, and decision making. An arcing fault is claimed when the measured voltage and current signals match the arcing fault model better than the nonarcing disturbance model. The method is tested on a modified standard test system using PSCAD/EMTDC considering different fault locations and scenarios. Simulation results show that the proposed detection method has high accuracy and is robust to fault distance, fault resistance, load current, and sampling rate. Laboratory experiments are also conducted to further validate the proposed method.

System and method for managing time for vehicle fault diagnostic apparatus

Abstract: Temporal contradictions and errors between controllers are eliminated and fault diagnosis is accurately performed by correct time. The system includes a master controller (1) for transmitting a measured time as a reference time, and a plurality of controllers (11a, 11b, 11c, ..., 11n) for determining the time relating to the fault diagnosis on the basis of the received reference time when fault data of sensors, etc., are detected.

Method and apparatus for testing a computer system through software fault injection

Abstract: One embodiment of the present invention provides a system for testing a computer system by using software to inject faults into the computer system while the computer system is operating. This system operates by allowing a programmer to include a fault point into source code for a program. This fault point causes a fault to occur if a trigger associated with the fault point is set and if an execution path of the program passes through the fault point. The system allows this source code to be compiled into executable code. Next, the system allows the computer system to be tested. This testing involves setting the trigger for the fault point, and then executing the executable code, so that the fault occurs if the execution path passes through the fault point. This testing also involves examining the result of the execution. In one embodiment of the present invention, if the fault point is encountered while executing the executable code, the system executes the fault point by: looking up a trigger associated with the fault point; determining whether the trigger has been set; and executing code associated with the fault point if the trigger has been set.

Sensor fault estimation and compensation for time-delay switched systems

Abstract: In this article, the problems of sensor fault estimation and compensation approaches for time-delay switched systems are investigated based on a switched descriptor observer approach. First, a novel time-delay switched descriptor state observer is proposed to estimate both the state and sensor fault. The proposed observer technique is also extended to systems with nonlinearities. Then, based on the estimation of the sensor fault, an efficient fault-tolerant operation can be realised via sensor fault compensation. Finally, an example is given to show the efficiency of the developed techniques.