Innovative solution to diagnosis and prognosis of defects and failures in cast-resin transformers for sustainable assets and risk management

Cast-resin transformers represent a small but significant and growing portion of the overall transformer market. They are employed in power distribution and in scenarios where a very low fire risk is mandatory. Evaluating operating conditions and estimating the residual life of transformers helps to provide sustainable solutions for Life Cycle Management (LCM) of electric service, loss prevention, and environmental protection. It follows that on-site and on-line measurement and assessment are particularly important to anticipate potential service interruptions, identify accumulated degradation, and schedule maintenance. Such monitoring activity was performed using a diagnostic and prognostic system that provided information on conditions (pathologies) of cast-resin machines because of several physicochemical properties. The study dates back to 2014, but research is still in progress. The results here presented refer to an innovative device designed, developed, and patented in 2018 (TRL 4-6) as the central component of the system. Data and information about VOC (Volatile Organic Compounds) and ozone formation (Resin Overheating and Corona Discharge), anomalous vibration insurgence (Mechanical Defect or Failures), and superficial temperature (Overheating and Overload) have been collected since 2017. The aforementioned device could sample surrounding air and trap organic molecules in specific cartridges to be analyzed by mass spectrometry. Two private companies (Power and Steel plants) offered to install devices on-site for validation. The acquired information was put through data analysis and interpretation processes through an Artificial Generative Intelligence (AGI) to spot anomalies and obtain trends and forecasting models. Research activities are still ongoing and moving towards an actual industrial application (TRL 9), which is forecasted to take place in 2024

Diagnostics of HV bushings through oil sampling and analysis: Experience with GSU transformers

Bushings are highly stressed parts of power transformers and their failures can lead to a transformer break-down. The diagnostics and predictive surveillance of bushings is essential for uninterrupted operation of transformers. Diagnostic tools applied include electrical tests, thermography and, to a minor extent, oil anal-ysis for oil-impregnated bushings. This paper gives a short review of bushing types and related applications, including procedures for in-field inspection and oil sampling. Dissolved Gas Analysis (DGA) issues in bush-ings’ mineral oil are briefly discussed and diagnostic criteria for DGA interpretation are given, comparing the experience of the authors with the available literature and standards

Diagnostics of HV bushings through oil sampling and analysis: Experience with GSU transformers

Bushings are highly stressed parts of power transformers and their failures can lead to a transformer break-down. The diagnostics and predictive surveillance of bushings is essential for uninterrupted operation of transformers. Diagnostic tools applied include electrical tests, thermography and, to a minor extent, oil anal-ysis for oil-impregnated bushings. This paper gives a short review of bushing types and related applications, including procedures for in-field inspection and oil sampling. Dissolved Gas Analysis (DGA) issues in bush-ings’ mineral oil are briefly discussed and diagnostic criteria for DGA interpretation are given, comparing the experience of the authors with the available literature and standards

A three-stage thermochemical conversion process for the production of biochar

Within a French consortium of four companies and five laboratories from two scientific groups, Sea Marconi is one of the industrial partners of the LORVER project (www.lorver.org). The project aims at the sustainable redevelopment of brownfield deriving from the deindustrialization of the Lorraine region (France) by soil reconstruction, cultivation of different non-food biomasses and their final conversion into valuable outputs (biochar, bioenergy, natural fibers, metals). Please click on the file below for full content of the abstract

On-load integrated treatment of giant power transformers in a severe scenario

The article describes the asset and risk management approach of a primary electrical company in the Middle East area. A specific maintenance strategy has been carried out for loss prevention of giant transformers, addressing mainly the corrosive sulfur. Starting from the international standards and considering the specific context, the appointed consultancy company GCC Lab selected the most efficient long-term mitigation technique: the selective depolarization. This process, developed and operated by Sea Marconi, is proven to be effective in the removal of DBDS and oil corrosive compounds, even after one year, also restoring all chemical and physical properties of the oil