Linear power networks - General theorems and quadrupoles

The first part of this article aims to set out the fundamental rules of linear network operation, commonly referred to as "general theorems". These theorems make it possible to study complex electrical networks and simplify many calculations. But every theorem contains assumptions, and it's important never to forget them. The first of these is contained in the title and will not be repeated at every stage: unless otherwise stated, the networks studied are linear. This applies both to this article and to those that follow. Other assumptions will be clarified as the article progresses.

The second part focuses on a particular type of network, with four terminals, called a quadripole. Very useful for establishing equivalent diagrams of real electrical elements, such as lines or transformers, the quadripole has properties that you need to know to be able to associate several elements, build and finally study a complete electrical network.