IEC TS 63471-2023 PDF

Full title and description

IEC TS 63471:2023 — DC voltages for HVDC grids. This Technical Specification gives a recommended series of nominal DC voltages for use in multi‑terminal and meshed HVDC power transmission and distribution systems (DC systems with nominal voltages above 1.5 kV). It is intended to support harmonization of nominal voltage levels to ease equipment design, system integration and future grid expansion.

Abstract

IEC TS 63471:2023 recommends a practical series of nominal DC voltage levels for HVDC grids (above 1.5 kV) and explains the purpose and application of nominal voltages (as distinct from rated or maximum system voltages). The document focuses on multi‑terminal and meshed HVDC networks where harmonized nominal voltages improve interoperability and reduce lifecycle costs; it does not mandate changes for standalone point‑to‑point projects but notes the benefit of forward‑looking alignment. Recommended nominal voltage points and guidance on their selection and economic considerations are provided.

General information

• Status: Published — Technical Specification (current/active as published).
• Publication date: 14 December 2023 (IEC webstore record). Some distribution platforms record delivery/release dates around 22–29 December 2023 or PD/adoption dates; the IEC record above is the base publication date.
• Publisher: International Electrotechnical Commission (IEC), TC 115 (HVDC).
• ICS / categories: 29.200; 29.240.01 (rectifiers/converters; power transmission and distribution networks).
• Edition / version: Edition 1.0 (2023).
• Number of pages: 8 pages (IEC webstore listing). Note: some commercial distributors or PD/adopted national versions list 10–12 pages depending on formatting or publication packaging.

Scope

The Technical Specification provides recommendations for selecting a nominal DC voltage series for HVDC grids with nominal DC voltages above 1.5 kV. It applies primarily to multi‑terminal and meshed HVDC transmission and distribution networks (grids) and to planning of new projects that may later become part of larger HVDC systems. The scope excludes prescriptive changes to standalone point‑to‑point HVDC links but encourages consideration of harmonized nominal voltages to facilitate future integration.

Key topics and requirements

• Definition and distinction of nominal DC voltage (rounded designation used for system level identification) versus rated or maximum DC voltages.
• Recommended nominal DC voltage series for HVDC grids (examples and preferred points). Typical recommended levels include 3 kV, 6 kV, 10 kV, 20 kV, 35 kV, 50 kV, 100 kV, 160 kV, 200 kV, 250 kV, 320 kV, 400 kV and 500/525 kV, with guidance on considering even higher levels (up to ~1100 kV) where economically feasible.
• Guidance on selecting nominal voltage to optimize capital and operational costs for multi‑terminal and meshed topologies.
• Application notes recommending that nominal voltages be used for system planning and interoperability, while device and equipment design still uses rated and withstand voltages per relevant product standards.
• Discussion of economic feasibility and scaling considerations for ultra‑high nominal DC voltages in very large transmission systems.

Typical use and users

This TS is intended for power system planners, transmission system operators, HVDC equipment manufacturers (converters, cables, switchgear), consultants, national standards bodies and project teams working on multi‑terminal or meshed HVDC grid projects. It is also used by stakeholders preparing functional specifications for HVDC grid projects and by committees working on HVDC grid interoperability.

Related standards

Typical related IEC and industry documents referenced in practice include: IEC TS 63291‑1 (guidelines and functional‑specification parameter lists for HVDC grid systems and converter stations), IEC TR 62543 (HVDC transmission using voltage‑sourced converters — VSC guidance), IEC 60633 (HVDC vocabulary), IEC 60071‑11 (insulation co‑ordination for HVDC systems), and IEC 60038 (IEC standard voltages). CIGRE technical brochures and other IEC/technical reports on HVDC grid design and protection are commonly used alongside this TS.

Keywords

HVDC, DC voltages, nominal DC voltage, DC grid, multi‑terminal HVDC, meshed HVDC, voltage series, TC 115, interoperability, insulation coordination.

FAQ

Q: What is this standard?

A: IEC TS 63471:2023 is a Technical Specification that recommends a harmonized series of nominal DC voltages for HVDC grids (systems with nominal DC voltages above 1.5 kV) to support planning and interoperability of multi‑terminal and meshed DC networks.

Q: What does it cover?

A: It covers guidance for selecting nominal DC voltage levels (distinct from rated or maximum voltages), a recommended set of nominal voltage points for HVDC grids, and advice on using those nominal values in planning to optimize costs and interoperability for multi‑terminal/meshed HVDC systems. It does not force changes on standalone point‑to‑point projects but recommends consideration of harmonization for future grid evolution.

Q: Who typically uses it?

A: Transmission planners, HVDC equipment manufacturers, system operators, consulting engineers, procurement and specification authors, and national standards bodies involved in HVDC grid development and multi‑vendor project specifications.

Q: Is it current or superseded?

A: It was published in December 2023 and is an active Technical Specification; the IEC webstore lists its stability date and related metadata with the document remaining current until the stability date indicated on the IEC record (see IEC publication record for the stability date). National adoptions or PD versions may show slightly different page counts or release records.

Q: Is it part of a series?

A: It is a stand‑alone Technical Specification developed under IEC TC 115 but is used alongside other IEC documents and technical reports on HVDC (for example IEC TS 63291‑1 for HVDC grid guidelines, IEC TR 62543 for VSC HVDC, IEC 60071‑11 for HVDC insulation coordination and IEC 60633 for vocabulary). These documents together form the normative and informative background for HVDC grid planning and equipment specification.

Q: What are the key keywords?

A: HVDC, nominal DC voltage, DC grid, multi‑terminal HVDC, meshed HVDC, voltage series, interoperability, insulation coordination.