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The paper addresses the problem of predictive maintenance in high power supply systems. According to FMECA (Failure Mode, Effects and Criticality Analysis) study key issues for power system reliability are the faults occurring in 3-phase high power transformers. With respect to the state of art where typically only thermal and electrical faults are monitored this work proposes a distributed network...
Preliminary exploration on simulation data mining with BP network and rough set method is made in advance. Then data mining method based on rough set theory and BP neural network is put up. Firstly, the redundant attributes in the decision-making table with rough set method is reduced, and the noise is filtered by BP neural network. Finally, rule set is generated by rough set from the reduction decision...
This paper discusses the use of vibrations for power transformer surveillance. Therefore, basic research of transformer vibration is presented including the physical background of vibrations and methods of measurement in terms of sensor techniques comparing in-oil and outside tank wall measurement. A case study of an outside tank wall measurement performed on an aged generator step-up transformer...
This paper aims to study the sensitivity of 500kv power transformer tank to winding vibrations. Through full analyses of winding vibration characteristics, tank mechanical characteristics and vibration differences in different positions on tank surface, the authors propose some evaluation criteria and principles on vibration measuring positions on the tank. Based on the principles, the relevant experimental...
Based on the analysis of the influence of the vibration and noise of the running transformer on China's power grid, the monitoring technology is studied. With the use of computer technology, communications technology and network technology, a web-based on-line monitoring system for the vibration and noise of the transformer is developed. With SQL Server 2000 as the database, the system uses the Winsock...
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...
The mechanical faults of a transformer are predicted with monitoring its vibration, which is a new technology put forward recently for condition based monitoring of transformers. The key technology of vibration method is how to identify the effective features of the vibration signal. Here, a new self-adapting time-frequency analysis method - local wave method which is developed from the empirical...
This paper is a study and share information of partial discharge measurement and vibration monitoring on power transformer. Power transformer is one of the critical components in power plant and transmission power system. Therefore, an appropriate maintenance program should be applied to the transformer in order to make power system more reliable and to prevent transformer failure at early stage....
This paper is concerned with the design and development of an on-line condition monitoring system for large power transformers utilizing signals such as transformer vibration, voltages, currents, temperature and state of switches. The system consists of two parts which communicate each other via Ethernet or series port. The formal is a front-end computer subsystem used for data acquisition and processing,...
The Condition Monitoring of On-Load Tap Changers is very important because they have proved to be the elements with noticeable failures in a power transformer. This article describes the development of a portable virtual instrument for monitoring this kind of elements. The monitoring task is based in the measurement and analysis of the vibrations that a tap change produces. In contrast with other...
Nowadays electrical utilities or industries are trying to monitor their electrical apparatus with online monitoring, without shutting the apparatus down. We are in PLN has taken this monitoring concept by applying vibration monitoring. This vibration monitoring has been applied to some of the transformers as a pilot project in PLN Region Jakarta and Banten. As voltage applied to the transformer, vibration...
ldquoDevelopment for advanced thermoelectric conversion systemsrdquo supported by the new energy and industrial technology development organization (NEDO) has been successfully completed as one of the Japanese national energy conservation projects. Three types of the cascaded thermoelectric modules operating up to 850 K in high electrode temperature and two types of Bi-Te thermoelectric modules operating...
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