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ABSTRACT: Um elektrische Betriebsmittel wirtschaftlich einzusetzen, ist es von Vorteil, ihren Nutzungsvorrat zu kennen. Mit Hilfe der
technischen Diagnostik werden signifikante Größen aufgezeichnet, aus denen man Rückschlüsse auf das zukünftige Betriebsverhalten
ziehen kann. Diese, das Betriebsverhalten beschreibenden Größen, entsprechen dabei Temperaturen, optischen, elektrischen und
mechanischen Variablen sowie der Kombination dieser Größen. Anhand dieser erhaltenen Daten lassen sich Veränderungen im Betriebsverhalten
diagnostizieren sowie Tendenzen erkennen und geeignete Gegenmaßnahmen ergreifen. Als ein Teilgebiet und somit wichtiges Diagnoseinstrumentarium
ist die Teilentladungsmesstechnik anzusehen. Dabei stehen für deren Detektion und Ortung unterschiedliche Methoden zu Verfügung.
To use electrical resources economically, it is useful to know the available remaining service life of used resources. With
the use of technical diagnostic systems significant variables can be recorded. On the basis of these variables (temperatures,
optical, electrical and mechanical variables etc.), conclusions concerning the future behaviour of the technical resources
will be made. Based on the received data information, modifications in the operation behaviour can be diagnosed; tendencies
can be detected and suitable counter measures can be set. The so-called “partial discharge measuring technique” can be regarded
as a subsection and an important diagnostic equipment. For the detection of partial discharges different methods can be used.
e & i Elektrotechnik und Informationstechnik 04/2012; 119(5):158-164.
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ABSTRACT: Partial discharge (PD) diagnostics was used to evaluate electrical insulations of high voltage equip-ment as a quality control and to detect insulation deterioration. Improvements, new developments as well as lower costs of sensors, electronics and processing units are some reasons for the increasing usage of PD measurements. The paper presents investigations in the area of optical partial discharge measurement technique. In an overview, PD measurement systems were presented, advantages and disadvantages of the optical method were discussed. An unconventional optical partial discharge detection system was devel-oped and comparative measurements to a conventional electrical PD measurement system were accom-plished. The system was tested by using a PD source in air or alternatively in oil to evaluate the sensitiv-ity and the impulse behaviour in correlation to the conventional measurement technique.
MATERIALS SCIENCE-POLAND 01/2009; 27. · 0.37 Impact Factor
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ABSTRACT: To ensure economic operation of high voltage equipment, reliable condition evaluation concepts are essential. They enable long-term inspection strategies with regard to a maximized service life of each component. Condition based maintenance (CBM) is therefore desirable and it is already used more and more in practice. Monitoring and diagnostic systems are on the way to get important tools for modern high voltage units or electrical equipment. With the help of modern monitoring techniques, it is possible to record and process significant parameters which is helpful for diagnostics. The quantity and magnitude of partial discharges (PD) are major quality characteristics in the assessment of high voltage equipment. For the PD measurements, different physical effects can be utilized, such as electrical, optical, acoustic, chemical and high-frequency effects. Therefore, in addition to the conventional PD measurements (according to IEC 60270), depending on the electrical equipment, a multiplicity of different alternative methods are currently being used. At the same time a distinction between on-and off-line measurements is possible. For new high voltage equipment, the direct integration of sensors for PD detection during production is practical as this enables the possibility of on-line measurements and furthermore a permanent operation monitoring. This paper deals with different possibilities for on- and off-line PD measurements in variety of electrical equipment. Moreover, new methods to measure and detect PD and the influence of interferences at on-site measurements are discussed.
Electrical Insulation and Dielectric Phenomena, 2008. CEIDP 2008. Annual Report Conference on; 11/2008
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ABSTRACT: Power transformers are one of the most important and also expensive components of the electrical power supply. In electrical networks, power transformers are of essential importance as interface between different system voltage levels. Due to the long manufacture process they are one of the most critical and high-priced equipment and so this is one of the reasons why condition monitoring becomes more popular. Monitoring systems as a basis for diagnostics open possibilities for expanding the operation time, reducing the risk of expensive failures and allow several maintenance strategies. With different monitoring techniques, detailed information about the transformer condition can be received and this helps to minimize the probability of an unexpected outage. This paper gives an overview about different monitoring and diagnostic methods and techniques, especially some example in the area of partial discharge (PD) and the frequency response analysis measurement.
Electrical Insulating Materials, 2008. (ISEIM 2008). International Symposium on; 10/2008
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ABSTRACT: In electrical networks are power transformers as interface between different voltage levels of essential importance. Due to the long manufacture process they are one of the most critical and expensive equipment and so this is one of the reasons why condition monitoring becomes more popular. Monitoring systems as basis for diagnostics open the possibility for expanding the operating time, reducing the risk of expensive failures and allows several maintenance strategies. With different monitoring techniques detailed information about the transformer condition can be received and helps to minimize the probability of an unexpected outage. As a traditional monitoring and diagnose techniques for transformer condition is the periodic sample of the transformer oil and to carry out a dissolved gas analysis. This paper gives an overview about different monitoring and diagnostic methods and techniques. With these systems significant parameters are recorded. Based on these measured variables conclusions of the future behaviour of the technical resources can be made. New developments in the area of signal measuring and conditioning, data processing and analysing as well as environmental aspects make a more precise and detailed condition evaluation possible.
Condition Monitoring and Diagnosis, 2008. CMD 2008. International Conference on; 05/2008
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ABSTRACT: Monitoring systems for condition evaluation are essential tools in the modern operation of high voltage equipment. Several new developments of insulation diagnostic are currently under discussion. Fibre optic technique was mainly used in the past as a galvanic separated, EMI-resistant data transmission. Today new developments in the area of signal acquisition offer an interesting possibility for temperature or force measurement by using fibre optic cable. These indicators represent significant parameters for a condition evaluation of electrical insulations and equipment. A potential free measurement inside the housing of the equipment is possible. Special point of interest is the condition evaluation of transformers. For example the temperature monitoring of high voltage power transformer is the key factor for an optimal operation (load limit, thermal rating). Therefore it must be guaranteed that the installation of these special fibre optic cables causes no additional disturbance like partial discharge inside the insulation system. In the paper, basic investigations of the PD behaviour of a test arrangement with implementation of fibre optic cables will be presented. Different materials like transformer board or plastics under air or oil test setup will be examined with different types of fibre optical sensor. The aim of these investigations will be the evaluation of the usability of fibre optical cables inside high voltage insulation systems.
Electrical Insulation and Dielectric Phenomena, 2007. CEIDP 2007. Annual Report - Conference on; 11/2007
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ABSTRACT: The knowledge of the condition of electrical equipment of power systems is a fundamental part for the reliability of energy systems. For the evaluation of the insulation condition of high voltage power equipment the partial discharge detection is one standard instrument. As diagnostic tool the partial discharge measurement is used in many applications, for testing and comparing different types of insulating materials and also to check complete devices or systems. Improvements, new developments as well as lower costs of sensors, processing and analysing units are some reasons for the increasing of PD diagnostic systems. This paper presents an overview about technologies for the optical partial discharge detection. Based on the emitted light produced by ionization, excitation and recombination processes during the discharge different parameters must be considered and diverse detection techniques are discussed. Additional some fundamental investigations of the discharge properties and their temporal behaviour in different insulation mediums were examined with a developed optical PD-detection system.
Electrical Insulation and Dielectric Phenomena, 2007. CEIDP 2007. Annual Report - Conference on; 11/2007
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ABSTRACT: Partial discharge detection is an effective method for monitoring and evaluation of dielectric condition of high voltage equipment and so an important part for technical diagnostic as the base for condition based maintenance. A variety of different techniques is available to detect the partial discharge activity. The measurements are carried out with electrical, acoustical, optical and chemical techniques. Beside the detection of the individual partial discharge impulse and its impulse behaviour with the conventional electrical methods, the exact localization of the partial discharges is very important for an efficient maintenance. Therefore unconventional methods, for example the acoustical or the optical detection, are in use. In a research project an optical partial discharge measurement system was developed. In this paper a comparison between the optical and the conventional electrical measurement system is carried out for different insulation media at a peak-plate arrangement
Electrical Insulation, 2006. Conference Record of the 2006 IEEE International Symposium on; 07/2006
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ABSTRACT: Insulation monitoring and diagnostic are the base of condition maintenance and essential for an economic usage of high voltage equipment. Electrical breakdowns in a small region of the insulating system are called partial discharge. The appearance and the intensity of these partial discharges are a quality criterion for an electrical equipment rating and therefore an estimation of the condition of the insulation system can be done. So the partial discharge measurement has become a fix part in industrial applications as a non destructive high voltage test. It uses the different physical effects in different insulating systems to detect significant parameters to give directly or indirectly information about the equipment condition. Not only high frequency electrical transient phenomena and especially currents are caused by partial discharges also optical, acoustical and chemical reactions and effects occur. Different techniques are in use to observe relevant parameters and are supposed to provide an early warning. In the full paper an overview of partial discharge measurement techniques, particularly in the area of non conventional measurements, for diagnostics is given
Properties and applications of Dielectric Materials, 2006. 8th International Conference on; 07/2006
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ABSTRACT: Due to the high electric fields at the surface of conductors of high voltage transmission lines, effects appear, which are called corona discharges. The electrical and acoustic emissions of dry and moistened high voltage transmission line conductors have been examined and evaluated. For this purpose several systems for sound and partial discharge measurement were used in a parallel arrangement. Contrary to dry kept overhead line conductors, the conductors moistened with water showed a changed appearance in acoustic and partial discharge measurement, which suggests mechanical movements of water drops in the changing electrical field producing acoustic sound. This effect is well-known, but until now an exact analysis of the arising acoustic emissions was neglected. This paper details the spectral analysis method used to evaluate these corona discharge noises and also describes the partial discharge measuring system.
Electrical Insulation and Dielectric Phenomena, 2004. CEIDP '04. 2004 Annual Report Conference on; 11/2004
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ABSTRACT: The partial discharge measurement is a very well known possibility to assess the quality of an insulation system. The aim is the detection of destruction in the electrical insulation as a result of electrical stress. In the working field of technical diagnostics, alternatives to the conventional partial discharge (PD) measuring techniques, with the aim of evaluating the insulation condition of electrical equipment are looked for. In a research project, a contribution in the area of optical partial discharge measurement technique and analysis was compiled. An optical partial discharge measuring system was developed, which gives the basis for investigations inside electrical equipment.
Electrical Insulation and Dielectric Phenomena, 2004. CEIDP '04. 2004 Annual Report Conference on; 11/2004
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ABSTRACT: According to some unexpected partial discharge (PD) test results
during off-line measurements of generators it must be assumed, that a
relative high humidity content of the ambient air considerably
influences the activities of external partial discharges. This
assumption could be verified by means of PD tests performed on models of
stator bars exposed to various climatic conditions. These tests have
shown, that activities of the external PD are strongly reduced, if the
ambient air humidity exceeds 50%. Consequently there is a risk of false
diagnosis under such circumstances
High Voltage Engineering, 1999. Eleventh International Symposium on (Conf. Publ. No. 467); 02/1999
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ABSTRACT: The partial discharge measurement is a very well known possibility to assess the quality of an insulation system of high voltage devices, because the life of high voltage equipment depends on the present of partial discharge. The aim is the detection of a beginning destruction in the electrical insulation as a result of electrical stress. A multiplicity of different partial discharge sources and their appearances show different physical and electrical characteristics. For the measuring, physical effects, such like optical, electrical and acoustical appearances, will be used. New methods for the detection of partial discharge have become more importance in last years. In the working field of technical diagnostics alternatives to the conventional partial discharge (PD) measuring techniques are looked for, with the aim to evaluate the insulation condition of electrical equipment.
Dielectric Liquids, 2005. ICDL 2005. 2005 IEEE International Conference on;
