1,700,896 research outputs found
Enhancement of reliability in condition monitoring techniques in wind turbines
The majority of electrical failures in wind turbines occur in the semiconductor components (IGBTs) of converters. To increase reliability and decrease the maintenance costs associated with this component, several health-monitoring methods have been proposed in the literature. Many laboratory-based tests have been conducted to detect the failure mechanisms of the IGBT in their early stages through monitoring the variations of thermo-sensitive electrical parameters. The methods are generally proposed and validated with a single-phase converter with an air-cored inductive or resistive load. However, limited work has been carried out considering limitations associated with measurement and processing of these parameters in a three-phase converter. Furthermore, looking at just variations of the module junction temperature will most likely lead to unreliable health monitoring as different failure mechanisms have their own individual effects on temperature variations of some, or all, of the electrical parameters. A reliable health monitoring system is necessary to determine whether the temperature variations are due to the presence of a premature failure or from normal converter operation. To address this issue, a temperature measurement approach should be independent from the failure mechanisms. In this paper, temperature is estimated by monitoring an electrical parameter particularly affected by different failure types. Early bond wire lift-off is detected by another electrical parameter that is sensitive to the progress of the failure. Considering two separate electrical parameters, one for estimation of temperature (switching off time) and another to detect the premature bond wire lift-off (collector emitter on-state voltage) enhance the reliability of an IGBT could increase the accuracy of the temperature estimation as well as premature failure detection
Condition And Monitoring Temperature Berbasis Mikrokontroler pada Motor Produksi di PT. Indah Kiat Pulp And Paper Perawang
For maintaning stabilitation of production machines in PT. Indah Kiat Pulp and Paper Perawang, it monitores everyday. Monitoring which is done one of about the temperature. It aims to avoid the damages in production machines because of over temperature. In temperature monitoring, the method is done by companies still based on manually with used thermo mini tool. Monitoring with used thermo mini tool need many times because there are many production machines. Beside that, that all are done in one month, thus the data is not real time. Because of that the writer designed condition and monitoring tool based on microcontroller with used temperature sensor LM35. Microcontroller arduino uno used wireless communication, it used RF 433 Mhz and graphic display used LabView software. The aims to give the real time data, quick and easy in monitoring.The result of the research which had been done stated that the condition and monitoring based on microcontroller in production machines in PT. Indah Kiat Pulp and Paper Perawang had been applied successfull. Percentage error ratio sensor LM35 based on microcontroller with thermo mini tool based on manually 1.02%. Speed of time in taking the data reach 5 second with effective interval connectivity RF 433 Mhz as far as 5 meter
Condition Monitoring of Power Cables
A National Grid funded research project at Southampton has investigated possible methodologies for data acquisition, transmission and processing that will facilitate on-line continuous monitoring of partial discharges in high voltage polymeric cable systems. A method that only uses passive components at the measuring points has been developed and is outlined in this paper. More recent work, funded through the EPSRC Supergen V, UK Energy Infrastructure (AMPerES) grant in collaboration with UK electricity network operators has concentrated on the development of partial discharge data processing techniques that ultimately may allow continuous assessment of transmission asset health to be reliably determined
On-line condition monitoring of transition assets
There are a number of medium voltage (MV) power distribution cable networks worldwide that are constructed predominantly of mass impregnated paper cables - London being one of these. Paper insulated lead covered (PILC) cables were extensively laid in the 50s and 60s before the introduction of cheaper polymeric alternatives that were sufficiently reliable. The current operational state of these networks has shown a gradual increase in failure rates of the previously reliable paper cables that are drawing to the end of their expected design life. Utilities are faced with the prospect of the impending failure of large sections of their prized asset and are keen to develop tools to better understand the health of their hardware. The analysis of partial discharge (PD) signals produced by the cables has been identified as a economically viable option to provide continuous condition monitoring of PILC cable circuits. Clearly, a comprehensive understanding of how PD activity relates to the various failure mechanisms exhibited by cable circuits in the field is required. A recently published technique for PD source discrimination was coupled with an understanding of the experiment and applied to the experiment data to isolate the signals specific to each degradation mechanism [1]. This technique has been applied to both rotation machines and transformer systems with promising results. PD signal discrimination is seen as the first step towards an autonomous condition monitoring futur
Interpretation of partial discharge activity in the presence of harmonics
Recent work has identified that circumstances of equipment operation can radically change condition monitoring data. This contribution investigates the significance of considering circumstance monitoring on the diagnostic interpretation of such condition monitoring data. Electrical treeing partial discharge data have been subjected to a data mining investigation, providing a platform for classification of harmonic influenced partial discharge patterns. The Total Harmonic Distortion (THD) index was varied to a maximum of 40%. The results show progressive development for interpretation of condition monitoring data, improving the asset manager's holistic view of an asset's health
Condition monitoring benefit for offshore wind turbines
As more offshore wind parks are commissioned, the focus will inevitably shift from a planning, construction and warranty focus to an operation, maintenance and investment payback focus. In this latter case, both short-term risks associated with wind turbine component assemblies, and longterm risks related to structural integrity of the support structure, are highly important. This research focuses on the role of condition monitoring to lower costs associated with short-term reliability and long-term asset integrity. This enables comparative estimates of life cycle costs and reduction in uncertainty, both of which are of value to investors
Condition monitoring and prognostic indicators for network reliability
Large-scale investment in transmission and distribution networks are planned over the next 10-15 years to meet future demand and changes in power generation. However, it is important that existing assets continue to operate reliably and their health maintained. A research project is considering the increased use of simulation models that could provide accurate prognostics, targeting maintenance and reduce in service failures. Such models could be further refined with parameters obtained from on-line measurements at the asset. It is also important to consider the future development of the research agenda for condition monitoring of power networks and with colleagues from National Grid, PPA Energy and the Universities of Manchester and Strathclyde, the research team are preparing a Position Paper on this subject
Designing Wind Turbine Condition Monitoring Systems Suitable for Harsh Environments
Research into wind turbine condition monitoring is continually receiving greater attention due to the potential benefits from condition monitoring systems (CMS). These benefits can only be realised with high reliability of the condition monitoring system itself. This paper discusses how CMS reliability can be increased, by introducing four types of robustness and how to design the CMS to meet these requirements. The paper uses a case study CMS installation to illustrate the design requirements, and lessons learned from the installation process
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