Engineering Recommendation (EREC) G99 was issued in July 2018 by the Energy Networks Association (ENA) and replaces the long standing EREC G59. The new G99 standard brings revisions to the application, performance, simulation and commissioning requirements when connecting new generation to the GB network.
Type A connections are fairly straightforward and not much different to the requirements under G59. Type B connections are now more involved, but the simulations are not that onerous, and no specific inverter model is required from the manufacturer. Type C and D simulations are more involved and lengthier, the key difficulty here is the requirement to have a fully functioning inverter model in DIgSILENT or PSS/E. In cases of types B, C and D studies should be carried out early in the project to ensure deadlines are met and any shortcomings in performance can be addressed early.
Check out our full review here:
To find out more about of Power Systems Studies offering check out our services here.