Grid codes with no ride-through curve — and why

64 grid codes are plotted in this dataset. 6 more are deliberately not, and this page says why for each one. A curve we cannot trace to a clause is worse than no curve: it looks authoritative, it gets copied, and the person who copies it has no way to find out it was wrong.

By Sergey Syrvachev — Director of Product Engineering, grid-scale BESS

The 6 exclusions

Three reasons recur: the document is paywalled and the curves are published only as bitmaps; the code delegates ride-through to each operator, so there is no single curve to plot; or the code defines no envelope for that event at all. The fourth case is the most useful — a curve circulating under the wrong name.

  • Germany — VDE-AR-N 4110 (MV) / 4120 (HV)Paywalled, with the limit curves published only as bitmaps. The candidate low-voltage curves for the two documents were byte-identical (not credible for different voltage levels), and the high-voltage candidate traced back to a legacy VDN-2004 voltage-relay setting rather than a ride-through envelope.
  • ENTSO-E RfG (Regulation (EU) 2016/631)RfG delegates every fault-ride-through parameter to each TSO within ranges (Arts. 14(3)(a) and 16(3)(a)), so there is no single "RfG curve" to plot. It also defines no high-voltage ride-through profile at all — Annex II Figure 3 is low-voltage only. The national implementations are plotted instead.
  • China — GB/T 36547-2024Paywalled. The candidate curves matched neither the 2018 nor the 2024 edition (wrong plateau duration, missing steps), so nothing is plotted pending access to the standard.
  • Japan — utility interconnection requirementsThe candidate low-voltage curve matched no Japanese requirement, and the Japanese requirement set defines no over-voltage ride-through table.
  • Canada — IESO (Ontario)IESO publishes no numeric voltage ride-through envelope. Curves previously circulating under an "Ontario" label are in fact the Alberta AESO tables, which are plotted here under Alberta.
  • High-voltage ride-through for UK G99, Ireland, France and the NetherlandsNone of these codes defines a high-voltage ride-through voltage-vs-time envelope. RTE explicitly defers it to a future edition of the DTR. Only their low-voltage (and, for G99, frequency) requirements are plotted.

Last reviewed with the rest of the dataset on . If one of these becomes tractable — an edition opens up, an operator publishes a numeric envelope — it moves to the chart and off this page.

If you need one of these for a project

An exclusion is not a dead end, it just means the number has to come from somewhere other than us:

  • Paywalled documents (Germany, China)Buy the current edition, and read the limit curve out of the figure yourself. Do not trust a redrawn version — the German low-voltage candidates we rejected were byte-identical across two different voltage levels, which no real code does.
  • Delegated frameworks (ENTSO-E RfG)Go to the connecting TSO's national implementation. RfG sets ranges, not values; the binding number is whatever your TSO chose inside them, and it differs across borders that share the same regulation.
  • Events the code does not define (HVRT for G99, Ireland, France, the Netherlands)There is no envelope to find. Confirm the obligation is genuinely absent rather than located elsewhere, and treat any HVRT figure quoted to you for these markets as unsourced until someone shows you the clause.