Download or read book Partial Discharge Detection for Evaluation of Insulation Integrity in Aerospace Electric Power System Wiring and Components Postprint written by and published by . This book was released on 2006 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report was developed under a SBIR contract. The paper describes the importance of partial discharge (PD) detection for aerospace electric power system wiring and components in low pressure environment. The relationships between recorded discharge pulse current waveforms and PD electrical characteristics are explained and discussed. Features of a new PD analyzer for low pressure applications are reviewed.
Download or read book Partial Discharge Detection and Analysis in Low Pressure Environments written by Xin Liu and published by . This book was released on 2006 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Typical aerospace vehicles (aircraft and spacecraft) experience a wide range of operating pressures during ascending and returning to earth. Compared to the sea-level atmospheric pressure (760 Torr), the pressure at about 60 km altitude is 2 Torr. The performance of the electric power system components of the aerospace vehicles must remain reliable even under such sub-atmospheric operating conditions. It is well known that the dielectric strength of gaseous insulators, while the electrode arrangement remains unchanged, is pressure dependent. Therefore, characterization of the performance and behavior of the electrical insulation in flight vehicles in low-pressure environments is extremely important. Partial discharge testing is one of the practical methods for evaluating the integrity of electrical insulation in aerospace vehicles. This dissertation describes partial discharge (PD) measurements performed mainly with 60 Hz ac energization in air, argon and helium, for pressures between 2 and 760 Torr. Two main electrode arrangements were used. One was a needle-plane electrode arrangement with a Teflon insulating barrier. The other one was a twisted pair of insulated conductors taken from a standard aircraft wiring harness. The measurement results are presented in terms of typical PD current pulse waveforms and waveform analysis for both main electrode arrangements. The evaluation criteria are the waveform polarity, magnitude, shape, rise time, and phase angle (temporal location) relative to the source voltage. Two-variable histograms and statistical averages of the PD parameters are presented. The PD physical mechanisms are analyzed. For PD pattern recognition, both statistical methods (such as discharge parameter dot pattern representation, discharge parameter phase distribution, statistical operator calculations, and PD fingerprint development) and wavelet transform applications are investigated. The main conclusions of the dissertation include: (1) The PD current pulse waveforms are dependent on the pressure. (2) The rise time of the waveform is another effective PD current pulse characteristic indicator. (3) PD fingerprint patterns that are already available for atmospheric pressure (760 Torr) conditions are inadequate for the evaluation of PD pulses at low pressures. (4) Various wavelet transform techniques can be used effectively for PD pulse signal denoising purposes, and for PD pulse waveform transient feature recognition.
Download or read book Partial Discharges PD written by Norasage Pattanadech and published by John Wiley & Sons. This book was released on 2023-07-31 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: PARTIAL DISCHARGES (PD) — DETECTION, IDENTIFICATION AND LOCALIZATION Explore state-of-the-art partial discharge measurement techniques In Partial Discharges (PD) — Detection, Identification and Localization, a team of distinguished electrical engineers delivers a comprehensive treatment of the behavior, modeling, measurement, monitoring, localization, and evaluation of partial discharges. It includes coverage of all major advancements in the field that have occurred over the last few decades. It also discusses partial discharge phenomena, detection methods, and strategies for analyzing and processing collected data. Mechanisms of insulation failure are explored, as is the denoising of partial discharge measurement data and the localization of partial discharge in large, high-voltage equipment. Non-electric principles and procedures are discussed, and the book offers a variety of tables, figures, and photographs to illustrate the concepts discussed within. Partial Discharges(PD) also provides: A thorough introduction to the physical behavior of partial discharges, including their causes and classification Comprehensive modeling of partial discharge behavior, including classical and dipole discharges Practical discussions of the measurement of partial discharges, including the electrical method, partial discharge decoupling, and pre- and post-processing of partial discharges In-depth examinations of the monitoring of partial discharge behavior, including methods and realization Perfect for electrical engineers engaged in electrical power engineering, Partial Discharges (PD) will also earn a place in the libraries of research and development specialists employed in the manufacturing, quality testing and operation of electrical systems.
Download or read book Partial Discharge Detection in High voltage Equipment written by F. H. Kreuger and published by Butterworth-Heinemann. This book was released on 1989 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review of current knowledge of electrical discharges that do not completely bridge the electrodes. Discharge detection, since 1945 and the use of new high voltage dielectrics, has grown into an indispensable tool for the evaluation of modern insulation. Topics covered include the behavior, detection and measurement of discharges, the choice of detection method and procedure, the location of discharges, and discharge detection in practice. Acidic paper. Annotation copyrighted by Book News, Inc., Portland, OR
Download or read book On line Non intrusive Partial Discharges Detection in Aeronautical Systems written by Cédric Abadie and published by . This book was released on 2017 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of power electronics in recent years has led to increase power density and to decrease pulse width modulation (PWM) voltage inverter cost. These developments have expanded the use of power converters for variable speed drive applications which enabled the development of the concept of "more electric aircraft". This concept consists in replacing one of energy carriers (pneumatic or hydraulic) with electrical energy. However, the deployment of electrical energy has increased the onboard voltage, which leads to premature aging of onboard electrical equipment. The shape of the PWM voltage consists of pulse trains. With the application of these pulses, the voltage is no longer homogeneously distributed along the coil. In this case, large differences in potential between the strands are present. In addition, another important parameter derived from the winding type motor used in industry. The random winding is the most common technique for low voltage motors due to its lower cost. The risk generated by this type of winding is that the first and the last turns of the first coil can be facing one another. In this case, up to 80% of the voltage will be supported by a few tens of microns of enamel, and existing insulation systems are not designed to withstand such severe constraints. The use of long cable connecting the inverter to the motor can also cause significant overvoltage at the motor terminals. This phenomenon is explained by the fact that the cable behaves as a transmission line to which the motor coils is not adapted in terms of impedance. In addition, these large potential differences associated with low pressures in the depressurized areas of the aircraft, may cause the occurrence of partial discharge. Partial discharges are electrical discharges that short-circuited partially the gap between two conductors. There are many detection methods well known under AC and DC voltage, however, in the case of the detection under PWM like voltage in low-voltage motors, the detection is much more complex. Partial discharge signals are embedded in the electromagnetic noise generated by the switching. The aim of this thesis is to develop a detection method and filtering method enabling a non-intrusive and an "on-line" partial discharges detection in the aeronautical field in order to qualify the electrical insulation systems used in aircraft.
Download or read book Detection Recording and Analysis of Partial Discharge in Electrical Insulation Using Computer Methods written by Peter Anthony White and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamentals of Partial Discharge Detection written by EB. Curdts and published by . This book was released on 1979 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: The sensitivity and calibration of partial-discharge detection systems is an important aspect of the general subject of partial-discharge measurements of products or structures involving electrical insulating materials. The primary objective is to perform a measurement, using a detection system having a sensitivity adequate to the purposes of the test, in the presence of inevitable electrical noise. Of equal importance is the matter of calibration which requires that fairly-accurate information be obtained as to the magnitudes of the changes that take place in the insulation system when it is stressed at some particular voltage.
Download or read book A New Approach to Partial Discharge Measurements for Testing Electrical Insulation Systems written by Alisdair Reid and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Partial discharge (PD) data has been recorded simultaneously using the conventional IEC60270 `apparent charge' measurement technique and the more recent Radio Frequency (RF) method. Due to the different responses of each system, combined measurement allows additional information on the nature of the PD source to be gained. PD was produced using a number of test cells containing PD sources typically encountered in practical insulation systems, such as free particles, floating electrodes and voids. When RF energy is plotted against apparent charge for a large number of discharges, characteristic patterns appear which may be used to distinguish between PD sources. Additionally, the combined technique has the ability to distinguish between simultaneously active PD sources by the appearance of multiple clusters. Additional work has been carried out to aid in the understanding and interpretation of these relationships. For example, an algorithm that models the complete response of a gas-insulated switchgear chamber has shown that PDs with a consistent pulse width produce correlation patterns that resemble a quadratic relationship. Additionally, direct PD current pulse measurement has shown a large variation in current pulse shape with faster rise times than previously expected (35 ps minimum). It is envisioned that the ability to relate RF measurements to the internationally accepted apparent charge level will aid in the general acceptance of the RF technique as a tool to quantify PD severity.
Download or read book Estimating and Pinpointing Partial Discharge Locations on Shielded Power Cables written by Zhifang Du and published by . This book was released on 1995 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Partial Discharge Detection in Medium Voltage Stators Using Two Independent Detection Schemes written by Akshay Bhure and published by . This book was released on 2017 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Partial Discharge Detection and Diagnostics Using Double sided Measurement written by Jichao Chen and published by . This book was released on 2014 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: Partial discharge detection and diagnostics have always been the major concerns of power cable quality evaluation. Based on the review of published literatures and the systems currently available on market, this ME thesis has proposed a new mathematical algorithm for double-sided PD measurement, which removes earth noise from the collected PD signals and localises the PD sources. This developed algorithm generally is comprised of wavelet de-noising, time domain reflectometry, time-of-arrival estimation and very low frequency cable testing criteria. It has been implemented on LabVIEW platform. PD signals are acquired by USB-5133 and then process through the algorithm. This system has a graphical user interface which is able to give users results of the de-noised signals from two cable ends and readings about the PD source location. This system has been tested at both signal and medium voltage levels. Signal level tests give results as expected that it has the minimum errors when the PDs occur near the centre of the cable and vice versa. It performs well for the PD signals with signal-to-noise ratio no less than 9.70 dB. Medium voltage level tests do not give sufficient results due to radiation phenomenon between two cable ends. However, by analysing the waveforms, it partially verifies the integrity of the developed system.
Download or read book Detection Recording and Analysis of Partial Discharges in Electrical Insulation Using Computer Methods written by P. A. White and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Engineering Design and Simulation written by Chenfeng Li and published by Springer Nature. This book was released on 2019-10-03 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book consists of selected peer-reviewed papers presented at the NAFEMS India Regional Conference (NIRC 2018). It covers current topics related to advances in computer aided design and manufacturing. The book focuses on the latest developments in engineering modelling and simulation, and its application to various complex engineering systems. Finite element method/finite element analysis, computational fluid dynamics, and additive manufacturing are some of the key topics covered in this book. The book aims to provide a better understanding of contemporary product design and analyses, and hence will be useful for researchers, academicians, and professionals.
Download or read book Corrosion Science and Technology written by David E.J. Talbot and published by CRC Press. This book was released on 2018-01-29 with total page 699 pages. Available in PDF, EPUB and Kindle. Book excerpt: Twenty years after its first publication, Corrosion Science and Technology continues to be a relevant practical guide for students and professionals interested in material science. This Third Edition thoroughly covers the basic principles of corrosion science in the same reader-friendly manner that made the previous edition invaluable, and enlarges the scope of the content with expanded chapters on processes for various metals and new technologies for limiting costs and metal degradation in a variety of commercial enterprises not explored in previous editions. This book also presents expertly developed methods of corrosion testing and prediction.
Download or read book Cyber Physical Systems of Systems written by Andrea Bondavalli and published by Springer. This book was released on 2016-12-16 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is open access under a CC BY 4.0 license. Technical Systems-of-Systems (SoS) – in the form of networked, independent constituent computing systems temporarily collaborating to achieve a well-defined objective – form the backbone of most of today’s infrastructure. The energy grid, most transportation systems, the global banking industry, the water-supply system, the military equipment, many embedded systems, and a great number more, strongly depend on systems-of-systems. The correct operation and continuous availability of these underlying systems-of-systems are fundamental for the functioning of our modern society. The 8 papers presented in this book document the main insights on Cyber-Physical System of Systems (CPSoSs) that were gained during the work in the FP7-610535 European Research Project AMADEOS (acronym for Architecture for Multi-criticality Agile Dependable Evolutionary Open System-of-Systems). It is the objective of this book to present, in a single consistent body, the foundational concepts and their relationships. These form a conceptual basis for the description and understanding of SoSs and go deeper in what we consider the characterizing and distinguishing elements of SoSs: time, emergence, evolution and dynamicity.
Download or read book Resilience and Risk written by Igor Linkov and published by Springer. This book was released on 2017-08-01 with total page 574 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume addresses the challenges associated with methodology and application of risk and resilience science and practice to address emerging threats in environmental, cyber, infrastructure and other domains. The book utilizes the collective expertise of scholars and experts in industry, government and academia in the new and emerging field of resilience in order to provide a more comprehensive and universal understanding of how resilience methodology can be applied in various disciplines and applications. This book advocates for a systems-driven view of resilience in applications ranging from cyber security to ecology to social action, and addresses resilience-based management in infrastructure, cyber, social domains and methodology and tools. Risk and Resilience has been written to open up a transparent dialog on resilience management for scientists and practitioners in all relevant academic disciplines and can be used as supplement in teaching risk assessment and management courses.
