Over the years, consumers have widely used different types of transformers in the electrical networks. In order to distribute power across various facilities in different locations, transformers are used to step up or step down the voltage levels to suit the electrical loads. Electrical networks of oil and gas facilities are extensively equipped with oil-filled transformers. The oil in the transformers, however, can be a major hazard to people, assets, and the environment in the case of major oil leaks or explosions. A fault and subsequent failure of the protection systems of transformers can lead to an explosion, a major hazard to the surroundings and environment.
The risk and effect of this danger varies based on several factors, including installation location, power rating of the transformer, oil type used, oil quantity, oil impurity, and protection systems provided. To prevent damage and the spread of fire if a transformer explodes, design engineers should take into account all necessary design measures in line with NFPA 850, Recommended Practice for Fire Protection for Electric Generating Plants and High Voltage Direct Current Converter Stations. Additionally, electrical system engineers and designers should consider additional protection systems and devices to prevent the explosion and hazards and safeguard people, assets, and the environment.
This paper discusses common failures of oil-filled transformers and any protective measures and solutions that can avoid transformer failure and a consequent loss of power or any destructive effects to safeguards for people, assets, and the environment.
The paper highlights various possible solutions and safety measures to consider when designing oil-filled transformers for a required installation. Some of these include adequate power rating, the selection of insulating oil, a suitable tank size, study of temperature rise, proper selection of protection devices, and selection of monitoring devices.
Additionally, this paper explains different methods and features available in the industry to protect the transformer and assets in case of any fault. These measures include internal built-in protections, external protections, and additional mitigation measures to avoid explosions.