Principle of operation of transformers can be easily understood from this article. Basic working principle of the transformer is mentioned very clearly and briefly
Electrical fuse is a simple, less resistive, self sacrificial and cheapest device used to interrupt a circuit under short circuit, excessive overload or over current conditions.
There are many methods used to cool the transformer. This article helps you to understand the various cooling methods followed in the transformer.
Have you have considered the power potential of the human body? What about the energy stored in a raindrop? In this article I discuss five strange methods that could one day become an integral way that civilization generates electricity.