High-Voltage Direct-Current (HVDC) applications for long
distance transfer of electricity have been used for several
decades. They have been used for point-to-point transfer and
been parts of the AC network. Electricity metering has been
made only on the AC side which means e.g. that transfer
losses cannot be separated from the conversion losses.
Recently, with voltage controlled HVDC it has been made
possible to design multi-point HVDC lines. It will important
in such grids to measure the transfer losses on the DC side in
order to distribute the cost of loss equitably. However, there
are no written standards for DC metering, and there is little
practical experience on what accuracy is achievable within a
reasonable effort. As part of an EMRP HVDC project, a set of
requirements and test equipment for HVDC meters are being
developed. It is important that these requirements can be met
with cost effective meter designs.