The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Power transformer is one of key equipment in power system and its normal operation guarantees reliability and safety of power transmission. In order to keep power transformer in good condition, regular inspection and maintenance is needed after equipment put into service. Various preventive test, on-line monitoring and portable test are must, but condition evaluation and fault diagnosis for power...
Transformer is an important substation device of power system and monitoring of its condition is imperative. IEC61850 standard as an international standard of substation communication networks and systems is aimed at harmonizing the current stand-alone substation automation systems and realizing the interoperation of intelligent electronic devices (IED) made by different manufacturers. This article...
This research work explores the feasibility of increasing system reliability by applying condition monitoring systems to selected circuit breakers and transformers. Smart grid technology decreases maintenance costs by deploying condition monitoring systems that informs the operator of impending failures or ameliorates those conditions. Since condition monitoring systems can themselves increase operating...
This paper introduced the concept of Proportional Hazards Model (PHM), it took advantage of the Weibull PHM to establish the failure rate model of transformer maintenance based on condition monitoring information. The failure rate threshold through the maximum availability method was determined, and then the maintenance decision model for the electric transformer was established. Finally, we used...
Transformers are a critical part of an electrical utility's asset base. Loss of a transformer in a utility, generation plant or process can cost many millions of dollars, depending on how long it is out-of-service. On-line monitoring and diagnostics is a useful tool to help operators to manage their assets and make decisions on continuing operation, maintenance or replacement. This paper illustrates...
Condition monitoring avoids serious economical losses resulting from unexpected failures and highly improves the system reliability and maintainability.In order to give an overall condition assessment ,the combination of the available condition monitoring data is much desired. In this paper, D-S (Dempster-Shafer) theory is introduced to dealing with condition assessment. Compared with traditional...
This paper describes the end-to-end components of an on-line system for diagnostics and anomaly detection. The system provides condition monitoring capabilities for two in service transmission transformers in the UK. These transformers are nearing the end of their design life, and it is hoped that intensive monitoring will enable them to stay in service for longer. The paper discusses the requirements...
Transformers play a significant role in power systems. The traditional method of transformer maintenance is time based or off-line-based, which is inefficient and costly. This paper MAS technique was introduced into synthetic fault diagnostic system for power Transformer. Where each agent served as an intelligent knowledge body or intelligent disposal method thus the diagnostic result was deduced...
With the expansion of electric capacity and large-scale extension of power grid, electric equipment is playing a significant role in modern life. At present, the technology of condition monitoring and fault diagnosing of power transformer has been made some improvement, yet its real-time performance and reliability still can't meet the requirement of safe production. Due to different thermal effects...
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...
Bushings failures are responsible for a large number of costly forced outages of transformers, breakers and reactors. Almost half of the bushing failures are catastrophic in nature and may pose danger to personnel and other equipment in vicinity. Many techniques are available for assessing the dielectric condition of oil-paper insulated power apparatus bushings. However, no single technique seems...
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,...
Distributed wireless sensor networks (WSNs) promise to change the way industrial systems and structures are monitored and controlled. This paper presents a WSN simulation model for a partial discharge (PD) WSN monitoring system for HV systems. A simulation model of a ZigBee sensor network has been simulated to be positioned at 6 locations of an HV transformer to record the PD readings and associated...
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...
Chinese power industry developed rapidly recent years, and the problem of safety and reliability of power equipment is increasingly outstanding. The development of new test technology and the introduction of artificial intelligence (AI) are driving the monitoring and diagnosing method on insulation condition forward, and nowadays gradually changing the maintenance strategy from breakdown maintenance...
Power transformers are important components of all electric networks. They are usually very expensive and therefore diagnosis and monitoring systems will be valuable for preventing damages. A continuous control of the status of the transformer condition is worthwhile and will support the appropriate decision in case of a problem. The transformers are geographically spread and with the aid of Internet,...
The monitoring systems of the transformer units are developed according to their loading guides, as their manufacturers specify. The problem that arises is due to the fact that the thermal models of the diverse versions of the loading guides do not yield similar results. Therefore, different values may be obtained for the same transformer unit with different monitoring systems. That is why the values...
The need for improved performance of power systems in terms of reliability and higher productivity has necessitated more and more application of condition monitoring techniques, which can provide early warning of potential failure with the opportunity of organizing avoidance strategies to minimize loss of time and unexpected costs. Periodic condition monitoring tests have limitations such as continuous...
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...
Power transformer is one of the most important components in the power system. The operating reliability of transformers mainly depends on their insulation status. An integrated system which contains the monitoring of gas-in-oil analysis (DGA), partial discharge (PD), contamination of the bushing surface, the equivalent capacitance and dissipation factor (tandelta) of the bushing is introduced in...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.