In a related post to last week, one of the interesting problems that has started to arise is National Grid ESO wanting the RMS simulation models handing over in an unencrypted format. This requirement has been around for a little while, but was not rigorously enforced by NG ESO, and tended to sidelined a bit. The requirements are not that obvious, unless you are familiar with the Grid Code, but are detailed in the Planning Code (PC) part of the code, and specifically in section PC.A.9.2.

Historically, models were often handed over with encrypted parts (usually the inverter and PPC model) and then the equipment suppliers would then hand over an unencrypted model of their own equipment directly to NG ESO, but it was a bit piecemeal and NG ESO have decided to clamp down as of September 2022 and are now refusing to issue an ION without the submission.

However, when you think about this at a practical level, this creates some difficulties. If the whole model should be unencrypted, then each component has to be fully open, so how is the achieved with most suppliers unwilling to handover unencrypted models to consultants, due to (very legitimate) IP concerns? There are solutions, but most of them are complicated and difficult to implement, and involve passing models backwards and forwards.

Considered against the backdrop of the requirements for EMT models to be submitted for equipment, perhaps we will be moving towards an approach where RMS models for inverter based resources are based on open generic designs that are an approximate of reality, using something like the WECC open models and equipment suppliers will move to giving specific settings for the open models, and the provide a detailed EMT model that is then considered accurate, in the way that usually occurs for modelling synchronous generator control schemes?