Grid forming

Grid forming lets a battery inverter run as a standalone voltage and frequency source. It can then supply loads on weak grids, or on grids with no conventional generation and no other inverters. On Tesla Megapack systems, the Mode Request parameter selects the mode: 1 is grid-following and 2 is grid-forming. Grid forming is only available on systems designed for it, and Tesla must enable it at commissioning. Tesla's grid forming can run off-grid (islanded), or on-grid to add virtual inertia. Tesla's design uses two parallel paths. A Virtual Machine behind a current-limiting impedance follows the voltage and frequency references, and a Power Dispatcher follows the real and reactive power setpoints. Compared with grid-following mode, it reaches power commands more slowly but reacts much faster to voltage and frequency changes. Enphase grid-forming (with backup) systems pair the IQ Battery 10C, IQ Combiner 6C and IQ Meter Collar with IQ9N, IQ8, IQ7 or IQ6 microinverters, or run as battery-only systems. IQ8 grid forming works only on 240 V AC interconnections, and the IQ8H-208 has no grid-forming function. A mix of IQ7 with IQ8 or IQ9N microinverters loses the Sunlight Jump Start (grid-forming PV) feature.

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• sentence 6: support check: partial - IQ8 240 V only and IQ8H-208 lacking grid-forming are stated, but the passage says a mixed IQ7 with IQ8/IQ9N system doesn't support IQ8- or IQ9N-specific Sunlight Jump Start, which is narrower than 'loses the feature' generally. -->