General requirements for substation wiring diagrams
High and very high voltage substations: role and structure

Within the network to which it is connected, each type of substation has to perform a number of well-defined functions on which its electrical diagram depends, generally represented in single-line form, with each three-phase circuit represented by a single line.

Choosing a substation electrical layout is a complex task, requiring the consideration of numerous technical, historical and economic conditions. Given the variety of network characteristics and the diversity of functions assigned to substations, it is not possible to draw up an exhaustive list of the technical conditions to be met. It is, however, useful to define the usual criteria for judging substation layouts, the weighted combination of which enables the designer to approach the desired function.

It should be noted that some criteria have opposite consequences, hence the need...