BS EN 62751-2:2014

1 Scope
2 Normative references
3 Terms, definitions, symbols and abbreviated
   terms
4 General conditions
5 Conduction losses
6 DC voltage-dependent losses
7 Losses in d.c. capacitors of the valve
8 Switching losses
9 Other losses
10 Total valve losses per HVDC substation
Annex A (informative) - Description of power loss
        mechanisms in MMC valves
Bibliography
Annex ZA (normative) - Normative references to
         international publications with their
         corresponding European publications

Provides the detailed method to be adopted for calculating the power losses in the valves for an HVDC system based on the 'modular multi-level converter', where each valve in the converter consists of a number of self-contained, two-terminal controllable voltage sources connected in series.

IEC 62751-2:2014 gives the detailed method to be adopted for calculating the power losses in the valves for an HVDC system based on the \'modular multi-level converter\', where each valve in the converter consists of a number of self-contained, two-terminal controllable voltage sources connected in series. It is applicable both for the cases where each modular cell uses only a single turn-off semiconductor device in each switch position, and the case where each switch position consists of a number of turn-off semiconductor devices in series (topology also referred to as \'cascaded two-level converter\'). The main formulae are given for the two-level \'half-bridge\' configuration but guidance is also given as to how to extend the results to certain other types of MMC building block configuration.