CIGRE Releases Technical Brochure 992 Establishing Global Standard for VSC-HVDC Station Insulation Coordination

Following the 2026 Paris Session, CIGRE has published Technical Brochure 992, "Application Guide for the Insulation Coordination of Voltage Source Converter ...

CIGRE Releases Technical Brochure 992 Establishing Global Standard for VSC-HVDC Station Insulation Coordination

Following the 2026 Paris Session, CIGRE has published Technical Brochure 992, "Application Guide for the Insulation Coordination of Voltage Source Converter (VSC) HVDC Stations," delivering long-awaited engineering benchmarks for converter valve halls up to ±800 kV.

Standardizing Dielectric Stress in Modular Multilevel Converters (MMC)

Authored by international utility and OEM experts across Working Groups B4.82 and A3.38, TB 992 establishes standardized calculation methodologies for fast-front transient overvoltages, lightning surges, and pole-to-ground DC faults.

The document provides rigorous clearance safety margins for indoor converter valve halls, DC gas-insulated switchgear (DC GIS), and high-frequency harmonic filter busbars operating under continuous DC bias voltage.

Arrester Sizing and Predictive Asset Monitoring Guidelines

A core section of the brochure details nonlinear metal-oxide surge arrester (MOSA) energy absorption sizing, protecting sensitive IGBT sub-modules from severe switching impulses during AC grid blackouts.

Transmission system operators globally are adopting TB 992 as the baseline engineering tender specification for upcoming 525 kV and 800 kV multi-terminal DC grids.