IEC 61400-24:2019

Overview

IEC 61400-24:2019 - Wind energy generation systems - Part 24: Lightning protection - defines requirements and methods for protecting wind turbines and wind power systems from lightning. This consolidated second edition replaces the 2010 edition and is restructured so the main normative requirements are separated from informative annexes. The standard covers the lightning environment, exposure and risk assessment, protection of blades, structural components, electrical and control systems, earthing, testing, documentation, inspection and maintenance. An annex provides guidance for small wind turbines.

Key topics and requirements

• Lightning environment & exposure assessment: Defines parameters of the lightning environment for wind turbines and methods to estimate annual lightning flashes and exposure for single turbines and farms.
• Risk assessment: Provides a framework to assess probability and consequences of lightning events (direct strikes and near flashes) and to quantify risk components for design decisions.
• Protection requirements:
  • Blades: Requirements, design considerations and test methods for blade lightning protection and verification.
  • Nacelle, hub, spinner, tower: Structural protection and verification methods.
  • Mechanical systems: Guidance for bearings, hydraulic systems, spark gaps and sliding contacts.
  • Electrical & electronic systems: LEMP protection, immunity levels, shielding, routing, surge protective devices (SPDs) and equipotential bonding.
• Earthing (grounding): Earth electrode arrangements, impedance targets, equipotential bonding and guidance for onshore, offshore and different tower/foundation types.
• Testing & verification: Laboratory and on-site test methods to validate compliance for components and systems.
• Documentation, inspection & maintenance: Required design documentation, manuals for LPS inspection, commissioning and periodic checks.

Applications and who uses this standard

IEC 61400-24 is used by:

• Wind turbine manufacturers (design & testing of blades, nacelles, electrical systems)
• Wind farm designers and asset owners (site exposure assessment, earthing and mitigation)
• Electrical and EMC engineers (LEMP protection, SPDs, shielding and routing)
• Certification bodies and testing laboratories (compliance verification)
• Field technicians and maintenance teams (inspection, repair, documentation)
• Safety and risk managers (risk assessment and mitigation planning)

Practical uses include designing lightning protection systems (LPS), specifying SPDs and bonding, defining test protocols, preparing maintenance procedures and demonstrating compliance for certification.

Related standards

• Other IEC standards covering wind turbines (IEC 61400 series)
• Applicable lightning protection, industrial electrical, and EMC standards (for earthing and LEMP/EMC compatibility)
• National/regional earthing and safety regulations

Keywords: IEC 61400-24, lightning protection, wind turbine lightning, risk assessment, LEMP, earthing, blades, surge protection, lightning protection level (LPL), lightning protection zones (LPZ).