IEC TS 63042-202:2021 PDF

Overview

IEC TS 63042-202:2021 - "UHV AC transmission systems – Part 202: UHV AC transmission line design" - provides common rules and main design principles for overhead AC transmission lines with highest voltages exceeding 800 kV. This IEC technical specification addresses electrical safety, reliable operation and practical engineering requirements for new construction, reconstruction and expansion of UHV AC overhead transmission lines. It consolidates guidance on clearances, insulation coordination, conductor and earth‑wire selection, tower and foundation design, and environmental performance.

Key topics and requirements

The technical specification covers core design areas engineers need for UHV AC overhead lines:

• Selection of clearances: air gaps, tower strike distances, phase‑to‑phase and ground clearances considering power‑frequency, switching and lightning overvoltages.
• Insulation coordination & insulator design: dielectric requirements, insulating materials, insulator string configurations and mechanical design of fittings.
• Bundle‑conductor selection: conductor types, number and spacing of sub‑conductors, ampacity, electromagnetic environment considerations, and mechanical strength.
• Earth wire / OPGW selection: choice of ground wire or optical ground wire, induced voltage considerations and UHV‑specific design criteria.
• Tower and foundation design: tower classification, geometry selection based on clearances, load calculations, design methodology, analysis tools and foundation types (shallow, raft, deep/pile).
• Environmental considerations: prediction and mitigation of electric and magnetic fields (EMF), corona and audible noise, radio‑interference, wind noise and landscape impacts.
• Reliability, safety and economy: general requirements to balance performance, safety limits and cost‑effective design solutions.

Annexes provide informative country‑level design practices and experimental results (examples from China, India, Japan) to inform real‑world implementation and environmental performance.

Practical applications and users

IEC TS 63042-202:2021 is intended for:

• Transmission system planners and design engineers working on UHV AC overhead lines
• Utility engineering teams upgrading or expanding extra‑high voltage networks
• Tower, conductor, insulator and OPGW manufacturers and suppliers
• Consultants performing insulation coordination, EMF/corona assessments and environmental impact studies
• Regulators and project owners developing technical specifications and procurement documents

Use cases include preparing design specifications, evaluating conductor/tower options, conducting insulation coordination studies, and assessing environmental mitigation measures for UHV projects.

Related standards

• Refer to other parts of the IEC TS 63042 series and applicable IEC/ISO standards for material tests, electromagnetic compatibility, and safety limits. Check the IEC webstore for the latest normative references and updates to ensure compliance.