Dear Colleagues,

Power transformers are one of the most important and critical components in power system networks. During its long service life, the transformer undergoes various stresses (electrical, mechanical, thermal, chemical etc.) which eventually degrade its dielectric as well as mechanical characteristics. The deterioration of transformer insulation characteristics reduces its dielectric strength, whereas winding deformation can result in internal faults. Gradual degradation of insulation characteristics and winding faults within the transformer during its service life can result in catastrophic failure and subsequently power interruption at the consumer’s end. The undesired interruption of power supply affects the production rate in heavy industries, which may result in huge monetary loss. In order to ensure a reliable power supply, the condition of transformers should be assessed regularly through employing advanced monitoring techniques. This Special Issue will cover the investigation of dielectric and mechanical characteristics of power transformers which are in service for a long period and are on the verge of ending their operating life. This Special Issue also invites contributions focused on the development of advanced techniques for monitoring the electrical characteristics and winding deformation of transformers for their reliability assessment to investigate further use in power system networks. Topics of interest for publication include but are not limited to:

• Investigation on moisture profile and aging characteristics of power transformer insulation;
• Diagnosis by chemical parameters;
• Dielectric spectroscopy in the time and frequency domain;
• Partial discharge diagnosis;
• Investigation on winding faults within transformers;
• Frequency response analysis of transformer windings;
• Reliability assessment.

Prof. Dr. Stefan Tenbohlen
Dr. Arpan Kumar Pradhan
Guest Editors

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• power transformer
• transformer insulation
• moisture
• aging
• partial discharge measurement
• transformer winding deformation
• condition monitoring techniques
• reliability assessment