IEC TR 62001-1:2021 is available as IEC TR 62001-1:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.

IEC TR 62001-1:2021 deals with the specification and design evaluation of AC side harmonic performance and AC side filters for HVDC schemes. It is intended to be primarily for the use of the utilities and consultants who are responsible for issuing the specifications for new HVDC projects and evaluating designs proposed by prospective suppliers. This document provides guidance on the specifications of AC filters for high-voltage direct current (HVDC) systems with line-commutated converters and filter performance calculation. The scope of this document covers AC side filtering for the frequency range of interest in terms of harmonic distortion and audible frequency disturbances. Where the term "HVDC converter" or "HVDC station" is referred to without qualification, in this document, it is understood to refer to LCC technology. It excludes filters designed to be effective in the power line carrier (PLC) and radio interference spectra. This edition includes the following significant technical changes with respect to the previous edition:
- general updating of the document to reflect changes in practice;
- 10.2.4 on fuseless capacitors has been transferred to IEC TR 62001-4;
- Clause 11 on future developments has been expanded;
- 10.3.3 and Annex F on voltage sourced converters have been deleted as their content is covered by IEC TR 62543.