A range of distribution transformers with multiple loading regimes

In the considerations of system design the determination of transformer ratings is an important factor. It is vital that the transformer can meet the peak load without distress either in the short or long term. Thus the concept of acceptable ageing is considered by reference to appropriate loading guides. The nature of the load variation will significantly affect the choice of transformer rating and the utilisation factor. One of the important factors affecting this choice is losses evaluation. The authors discuss this factor and how it affects the ageing of the insulation. Alternative design concepts, a high temperature design and a hybrid design for the transformer insulation are discussed. The economic benefits of the new designs are compared to the conventional design