Standard LIWV from IEC 60071-3 for ±500 kV: choose 1050 kV (closest standard value).
April 18, 2026 Abstract High-voltage direct current (HVDC) transmission systems are critical for long-distance bulk power transfer and asynchronous grid interconnection. Unlike AC systems, HVDC converter stations face unique insulation stresses, including DC steady-state voltages, polarity reversals, harmonic components, and steep-front switching impulses from valve operations. IEC 60071-3, part of the international insulation co-ordination series, provides systematic procedures for selecting insulation levels and clearances within HVDC converter stations. This paper reviews the principles, methodologies, and application steps of IEC 60071-3. It discusses voltage definitions, representative overvoltages, co-ordination withstand voltages, and required withstand voltages for both line-commutated converters (LCC) and voltage-source converters (VSC). Practical examples and comparison with IEC 60071-1 (AC systems) are provided to highlight key differences. The paper concludes with current challenges and future revisions related to hybrid HVDC systems and compact station design. Iec 60071-3
[University/Department – For academic purposes] Standard LIWV from IEC 60071-3 for ±500 kV:
Assume ( k_sa = 1.10 ) (indoor valve hall) → ( U_rw = 920 \times 1.10 = 1012 , \textkV ) Practical examples and comparison with IEC 60071-1 (AC
Insulation Co-ordination for HVDC Converter Stations: A Comprehensive Review of IEC 60071-3
For DC withstand: ( U_cw,DC = 630 \times 1.10 = 693 , \textkV ) → ( U_rw,DC = 693 \times 1.10 \approx 762 , \textkV ). Standard DC test voltage = 750 kV (1 min).