1 Scope
This document defines aspects on planning, specification, and execution of multi-vendor
HVDC grid systems also referred to as HVDC grids. The terms "HVDC grid systems" or "HVDC grids" are used in this document to describe HVDC systems for power transmission having more than two HVDC stations connected to a common DC circuit. The DC circuit can be of radial or meshed topology
or a combination thereof. In this document, the term "HVDC grids" is used.
While this document focuses on requirements specific for HVDC grids, some requirements are considered applicable to all HVDC systems in general, i.e., including point-to-point HVDC systems. Existing IEC (e.g., IEC TR 63363‑1 [1]), Cigre or other relevant documents have been used for reference as far as possible.
Corresponding to electric power transmission applications, this document is applicable
to high voltage systems, i.e., those having typically nominal DC voltages higher than 50 kV with respect to earth are considered in this document.
NOTE While the physical principles of DC networks are basically voltage independent, the
technical options for designing equipment get much wider with lower DC voltage levels,
e.g. in the case of converters or switchgear.
This document covers technical aspects of:
coordination of HVDC grid and AC syste...