FNN Recomendation

Voltage Regulating Distribution Transformer (VRDT) – Use in Grid Planning and Operation

The FNN Recommendation was produced by the "Voltage Regulating Distribution Transformer"
project group at Forum Netztechnik/Netzbetrieb im VDE (FNN). VDE is the Association for Electrical, Electronic & Information Technologies.

The aim of this FNN Recommendation is to describe the basic function of the VRDT and to present possible applications in grid planning and operation. This document contains a collection of experiences gained with the technology in a number of projects and is intended for grid planners and project planners, e.g. at utilities or service providers, to assist with decisions about whether VRDT use is feasible and if so in what form. This document answers the following questions:

• What standards and terms are relevant to VRDTs?
• How does the design of a VRDT differ from that of a conventional transformer?
• In what applications does the use of a VRDT present a technical and economical solution?
  How can these applications be identified?
• What aspects need to be taken into account when planning a VRDT?
• What aspects should be taken into account when operating a VRDT?

Please click here to download the document.

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