Power Transformer Online Monitoring using Electromagnetic Waves explores how to use electromagnetic wave technology and remote monitoring systems to predict and localize costly mechanical defects and partial discharge challenges in high voltage transformer windings. This innovative approach brings several potential benefits compared with conventional techniques such as frequency response analysis, including impermeability to ambient noise, and online implementation capability. This book reviews both fundamental and state-of-the-art information about all key aspects of condition monitoring using electromagnetic waves. It addresses the simulation of power transformers in CST environment while also explaining the theoretical background of boundary conditions used. Chapters review how to achieve practical online implementation, reliable diagnosis, asset management and remnant life estimation. Partial discharge detection is also discussed. - Discusses the advantages and disadvantages of the electromagnetic wave method in comparison with classical monitoring methods - Explores how to design and implement power transformer monitoring systems using electromagnetic waves - Investigates partial discharge detection and localization in addition to the partial discharge emission effects on defect detection

The aim of this book is to familiarize the reader with the concept of electromagnetic time reversal, and introduce up-to-date applications of the concept found in the areas of electromagnetic compatibility and power systems. It is original in its approach to describing propagation and transient issues in power networks and power line communication, and is the result of the three main editors' pioneering research in the area.

The reliability of electrical energy networks depends on the quality and availability of their electrical equipment, e.g., power transformers. Local failures inside their insulation can lead to breakdowns resulting in high outage and penalty costs. To prevent these destructive events, power transformers are tested for partial discharge (PD) activity in a routine test before shipment. Furthermore, PD activity can be evaluated as a diagnostic measurement on-site (on-line or off-line) or be constantly monitored during service using the ultra-high frequency (UHF) method. In this thesis, a calibration procedure is proposed for the UHF method used in power transformers, which is lacking so far. The calibration process is required to ensure both reproducibility and comparability of UHF measurements. Only a calibrated UHF measurement procedure can be deemed reliable and eventually be introduced to supplement in (site-)acceptance tests of power transformers. The proposed calibration method considers two factors: The influence of the UHF sensors' sensitivity and that of the UHF instrument characteristics, including accessories like cables, pre-amplifier, etc. The UHF instruments' influence is corrected by using a defined and invariable test signal as a reference for all recording devices comparable to the calibration method used in IEC 60270 for electrical PD measurement. The sensitivity of the UHF sensor is addressed by a characterization of UHF sensors using the antenna factor (AF) measured in a special reproducible setup, i.e., a GTEM cell. In this thesis, a self-built GTEM cell is presented, which is oil-filled to address the environmental conditions inside a transformer where the sensor will be used. With such a cell, influences on the AF of UHF sensors are investigated, and it is shown that sensor sensitivities measured in an air-filled cell can be corrected to the oil environment. A practical evaluation of the proposed calibration procedure is performed in a laboratory setup on a distribution transformer with different UHF instruments and sensors using artificial PD signals and real high voltage driven PD sources. Finally, this thesis identifies future research topics, which may be needed to improve the proposed UHF calibration procedure for power transformers and the UHF method in general.

High voltage engineering is extremely important for the reliable design, safe manufacture and operation of electric devices, equipment and electric power systems. The 21st International Symposium on High Voltage Engineering, organized by the 90 years old Budapest School of High Voltage Engineering, provides an excellent forum to present results, advances and discussions among engineers, researchers and scientists, and share ideas, knowledge and expertise on high voltage engineering. The proceedings of the conference presents the state of the art technology of the field. The content is simultaneously aiming to help practicing engineers to be able to implement based on the papers and researchers to link and further develop ideas.

High voltage engineering is extremely important for the reliable design, safe manufacture and operation of electric devices, equipment and electric power systems. The 21st International Symposium on High Voltage Engineering, organized by the 90 years old Budapest School of High Voltage Engineering, provides an excellent forum to present results, advances and discussions among engineers, researchers and scientists, and share ideas, knowledge and expertise on high voltage engineering. The proceedings of the conference presents the state of the art technology of the field. The content is simultaneously aiming to help practicing engineers to be able to implement based on the papers and researchers to link and further develop ideas.

This book is a printed edition of the Special Issue "Power Transformer Diagnostics, Monitoring and Design Features" that was published in Energies