IEC TR 60919-1:2020 RLV contains both the official IEC International Standard and its Redline version. The Redline version is not an official document, it is available in English only and provides you with a quick and easy way to compare all the changes between the official IEC Standard and its previous edition.

IEC TR 60919-1:2020(E) provides general guidance on the steady-state performance requirements of high-voltage direct current (HVDC) systems. It concerns the steady-state performance of two-terminal HVDC systems utilizing 12-pulse converter units comprised of three-phase bridge (double-way) connections, but it does not cover multi­terminal HVDC transmission systems. Both terminals are assumed to use thyristor valves as the main semiconductor valves and to have power flow capability in both directions. Diode valves are not considered in this document. This edition includes the following significant technical changes with respect to the previous edition:
- Figure 8 and Figure 20 have been updated, a new Figure 18 "LCC/VSC hybrid bipolar system" has been added;
- the HVDC system control objectives have been supplemented;
- additional explanations regarding the HVDC system control structure have been given;
- a new subclause 13.6 on HVDC system protection has been added.