User P-Q diagram as a tool in reactive power trade

Trading with reactive power will soon become a very important part of electric energy trade. However, while trading, voltage regulation in portable and distribution systems must not be neglected. In order to balance the technical and economic aspects it is necessary to be familiar with the electric power system, the source of electric energy most of all, meaning the synchronous generator and its possibilities. These possibilities are shown in the synchronous generator P-Q diagram. We nowadays use static P-Q diagrams, provided by generator producers, which in most cases refer only to generators. This article presents a dynamic user P-Q diagram containing changeable parameters and showing a real availability of a synchronous aggregate.