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Electrical and Electronic Properties of Expanding Polymers
Published in Rajender K. Sadhir, Russell M. Luck, Expanding Monomers, 2020
The subject of partial discharge is a major area of study for researchers concerned with reliability of electrical equipment.2 Whether partial discharges occur is also dependent upon the size of the voids. The influence of void diameter on breakdown strength of air (in a polymeric insulation) can be estimated from Paschen’s curve. Figure 2 shows the relationship, as calculated from information provided by Bahder et al.3 Although this calculation was performed from studies on polyolefins, it is applicable to all electrical insulation, i.e., the breakdown strength of air in a void does not depend upon the polymer nature. However, the polymer response to the energy released will be highly dependent upon the polymer nature.
Photonics and Its Application in High-Voltage Engineering
Published in Tarun Kumar Gangopadhyay, Pathik Kumbhakar, Mrinal Kanti Mandal, Photonics and Fiber Optics, 2019
Electrical energy is a driver of growth for a nation, and it is having a direct impact on its economic growth and its per capita electricity generation and consumption. In addition to the above, uninterrupted power supply is of prime importance for any nation, as sudden outage of electrical equipment may cause interruption of power supply, making high financial and social impact. Insulation plays a fundamental role to assess the equipment quality and life, especially for high-voltage (HV) apparatus, which are the most critical and costly component in any power system. In an HV power apparatus, partial discharge is due to defects of insulation; it is also due to non-linear combined stress of thermal, electrical, mechanical, ambient and human effects on it.
Potential Applications in Electric Power and Electronics Sectors
Published in Toshikatsu Tanaka, Takahiro Imai, Advanced Nanodielectrics, 2017
Takahiro Imai, Yoshiyuki Inoue, Masayoshi Nagata, Tetsuo Yoshimitsu, Kazutoshi Goto, Takanori Kondo, Takashi Ohta
Occurrence of partial discharge can be measured by various methods such as detection of high frequency voltage fluctuations or pulse current caused by a discharge phenomenon, light or electromagnetic waves emitted by discharge, or chemical changes of gas caused by a discharge arc. In a conventional AC partial discharge measuring instrument, a measuring technique that supports an impulse voltage having an unmeasurable short rise time is studied and, as a sensor for the measuring technique, a high frequency current transformer (CT), photomultiplier tube, horn antenna, macro-strip (patch) antenna, directional coupler, or the like is used [1].
Rapid discharge detection via pure Hilbert phase retrieval on interferometry
Published in Journal of Modern Optics, 2022
Jiahao Xu, Yawen Liu, Shasha Yuan, Chao Jiang, Liang Xue, Fenghong Chu, Youhua Jiang
The detection methods of partial discharge generally include the pulse current method, ultrasonic detection method, chemical detection method and optical detection method [1–13]. Sahoo et al. used the pulse current method for partial discharge detection, which has the advantages of high sensitivity and the ability to obtain the true discharge volume, but the measurement results have less information and poor anti-interference [14]. Markalous et al. localized the flaw by means of arrival times of acoustic PD signals. However, in actual operation, due to the complexity of the mechanical structure and the barrier effect of the medium, the ultrasonic signal will be attenuated [15]. Ji et al. evaluated the severity of partial discharge by gas chromatography of the SF6 content in the discharge process, but the chemical detection method can only qualitatively describe the level of discharge energy, and cannot calibrate the discharge volume [16]. For the early warning detection of partial discharge, it is hoped that the more sensitive the better, and the faster the better, so the research team used the interference detection in the optical detection to improve the sensitivity.
Recognition of Fused Partial Discharge Patterns in High Voltage Insulation Systems: A Hybrid DCNN and SVM Based Approach
Published in IETE Journal of Research, 2022
I. Aruna Devi, R.V. Maheswari, R. Rajesh
The Partial Discharge mechanism is defined as a localized electrical discharge that only partially bridges the insulation between conductors and which can or cannot occur adjacent to a conductor as per IEC Standard 60270 High Voltage Test Techniques – Partial Discharge measurements [1]. Partial discharge monitoring plays a vital role in evaluating the condition of the insulation system and thereby improves the stability and reliability of the power system. The occurrence of PD mechanism can be considered as an early indication of insulation failure and it can be diagnosed by using either online or offline condition monitoring techniques. The type of defects that account for PD generation in high voltage power system apparatus are the voids, cracks, and some de-laminations that are present within the insulation. The PD signals generated due to these faults, tend to show a high rate of similarity in their patterns which makes it difficult to identify their sources [2]. Some of the methods that are proposed for PD detection are pulse current method, ultra-high-frequency method (UHF), dissolved gas analysis (DGA), acoustic method, and optical method [2–4]. The identification and classification of PD patterns are done by using their statistical parameters like the magnitude of charge, number of discharges per cycle, Skewness factor that represents the asymmetrical distribution of PD signals, Kurtosis representing the sharpness of PD distribution, rise and fall time of the PD pulses, width and area of the PD pulses, discharge factor denoting the mean discharge value of the signals, correlation and complexity factors that are used to discriminate the changes in shapes of the PD signal distribution, etc [5,6].
Partial Discharge Detection and Localization in Power Transformers based on Acoustic Emission: Theory, Methods, and Recent Trends
Published in IETE Technical Review, 2021
Viral B. Rathod, Ganesh B. Kumbhar, Bhavesh R. Bhalja
According to IEC-60270, “Partial discharge is a localized electrical discharge that only partially bridges the insulation between conductors and which can or cannot occur adjacent to a conductor” [1]. In other words, “Partial discharge is a localized dielectric breakdown (which does not completely bridge the space between the two conductors) of a small portion of a solid or liquid electrical insulation system under high voltage stress”.