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A continuous real-time data acquisition and communication equipment based on Advanced RISC Machine and Field Programmable Gate Array is designed and developed, on the basis of which an on-line monitoring and fault diagnosis system for high voltage circuit breaker is realized. Mechanical, electrical and environmental parameters of the switching process can be gathered by this system. The function modules...
In this paper Principal Components Analysis (PCA) is used for detecting faults in a plant with multiple operation modes. PCA reduces the dimensionality of the original historical data by projecting it onto a lower dimensionality space. It obtains the principal causes of variability in a process. If some of these causes change, it can be due to a fault in the process. The classical PCA approach confuses...
In modern drive applications fed by voltage source inverters, monitoring systems are of advantage to reduce the maintenance costs and prevent outages. The proposed insulation monitoring method detects stator insulation defects by evaluating the current's transient response after step excitation by the inverter. Due to fast switching of the voltage source inverter at high output voltage dv/dt rates,...
This paper presents an intelligent detection algorithm based on BP Neural Network, which is based on the current curve change rule of the turnout switch machine. Firstly it analyzes characteristics of each stage of turnouts device operating current curve, summarizes the typical turnout fault operating current curve; Then, establishes the mapping data sets between the action current and turnout fault...
This paper presents model based approach for diagnosis of open circuit power switch faults in full bridge DC-DC converter of a photovoltaic system. The control circuitry of the proposed converter monitors and regulates output current, whenever output current lowers, controller monitors current at test points and localizes faulty switch by comparing fault features. This minimizes efforts required for...
Reconfiguration plays a vital role in resource utilization. The functional, interconnect testing of digital circuits is done using Boundary Scan Trainer (BST) kit. The faulty cores if replaced by spare ones in real time reduce the switching time. This procedure is implemented in wireless network system also. The proposed work focuses on wireless communication among nodes, grouping them as different...
At present, the temperature monitoring of contact terminal is not integrated into the available intelligent manipulation device for high-voltage switchboard. To develop a high-voltage switchgear comprehensive system of on-line monitoring and fault diagnosis which can measure the contactor temperature rise is very important to guarantee the normal operation of the high-voltage switchgear. Design on...
In comparison to rotor bar fault detection for mains fed induction machines the detection in inverter-fed drives is especially challenging. The most important reasons are the disturbances introduced by the fast switching of the inverter. Moreover the fault indicator is influenced also by control dynamics and load changes. In addition most known fault detection technologies need a certain load level...
This paper describes the problems generally faced with PLC based control systems and a general procedure to solve them. Flowcharts for troubleshooting of power supply faults, internal and external problems of PLC has been included in the paper. The approach mentioned for troubleshooting is general and can be applied on any type of PLC based control system. A case study is included to validate the...
This paper presents a methodology for fault detection and monitoring of a class of hybrid process systems modeled by switched nonlinear systems with control actuator faults, uncertain continuous dynamics and uncertain mode transitions. A robust hybrid monitoring scheme that distinguishes reliably between faults, mode transitions and uncertainty is developed using tools from unknown input observer...
Timed failure propagation graph (TFPG) is a directed graph model that represents temporal progression of failure effects in physical systems. In this paper, a distributed diagnosis approach for complex systems is introduced based on the TFPG model settings. In this approach, the system is partitioned into a set of local subsystems each represented by a subgraph of the global system TFPG model. Information...
Contact burning is one of the main faults of transformer on-load tap changers (OLTC). If contact burning fault diagnosis is not timely, the decreasing contact area, increasing contact resistance and the increasing arc and heat during the witching processes will cause further burning. Researches on contact burning failure were done and a feature analysis method based on wavelet packet energy entropy...
This work considers incipient fault diagnosis and prognosis for hybrid systems with unknown mode changes. A set of augmented analytical redundancy relations (ARRs), termed AARRs, is proposed to extend the capability of ARRs to identify degradation of components which are not represented by physical parameters. The methods utilize the unified constraint relations, named global AARRs (GAARRs), for health...
To achieve the strict requirements for rapidness of data acquisition and the precision of data transmission during the on-line monitoring system of the condition of circuit breaker, a design approach for real-time data acquisition and remote transmission system base on field programmable gate arrays (FPGA) and ARM technology is presented. The approach adopts an overall structure of FPGA + ARM + ICC...
Hybrid Dynamical Systems (HDS) constitute a wide class of common industrial applications, where the behavior is determined by the interaction between continuous and discrete dynamics, i.e. behavioral modes succession. The general principle of model-based Fault Detection and Isolation (FDI) algorithms is to compare the expected behavior of the system, given by a model, with its actual behavior, known...
In this paper the development of protection schemes for multi-phase and phase-to-ground faults in autonomous micro-grids is dealt with, accounting for the fact that a distribution ldquoislandrdquo can be intentionally intended to operate for a long time duration (e.g. during maintenance in the main upstream network or due to economic advantages for the micro-grid electrical customers). The definition...
Online monitoring and fault diagnose system of electrical device is one of the main research directions in the electric field. It is also one of the key technologies for settling the decision problems of reliability, safety and maintenance. STATCOM is a kind of large Flexible AC Transmission System device which is used more and more widely. As its cost and complicated degree are high, it is especially...
The rapid growth in complexity of the automotive ECU (Electronic Control Unit) networks has posed challenges in real-time network management, which collects network information for fault diagnostic systems. This paper proposes a dynamic network management framework based on the OSEK Network Management protocols, which can automatically adapt to the unstable network load. A method to calculate appropriate...
Network fault diagnosis is an important aspect of network management. Often, a single component failure will result in a cascade of secondary faults that overwhelm simple reasoning approaches. If the network monitoring information is being transmitted through the network to the network management system (NMS), then fault diagnosis is complicated by the fact that the transmission of relevant monitoring...
In this paper we present a low cost fault-tolerant attitude determination system to a scientific satellite using COTS devices. We related our experience in developing the attitude determination system, where we combine proven fault tolerance techniques to protect the whole system composed only by COTS from the effects produced by transient faults. We detailed the failure cases and the detection, reconfiguration...
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