Auxiliary transformer cooling systems

Transformer overheating is a most undesirable condition, as it severely attacks the insulating system ? both oil and paper. Deterioration of this system is responsible for the majority of all transformer failures. Newer units which do not possess significant overdesign are even more susceptable to thermal damage. This paper discusses different types of heat problems, whether due to overload, environmental conditions, color of tank coatings, or oil condition and show how these problems can be alleviated, perhaps with the use of a properly engineered external cooling system. A hot operating transformer does not necessarily warrant a cooling system, but in the event it does, applying a shelf model heat exchanger shows poor judgement. Transformers are the backbone of modern production and careful engineering must be practiced when contemplating alternate performance or the addition of any auxiliary equipment. A cooling systems heat transfer capability measured in kilowatts (KW) is, of course, most important. However, considerations such as proper bleeding and removal of incidental air from the system, shutdown upon malfunction, system efficiency and overall dependability and safety can not be ignored.