Not only dose the device produce DC, it is dumping it into a Capacitor and the power for the grid will be bleed off from the Capacitors so from the perspective of the Inverter that will supply the grid their aren’t even any pulses, their is just a HVDC source that might have some variation in it’s voltage but is not dropping to zero 200 times a second so the whole premise of the thread is unjustified.
As for the grid becoming DC, that’s more likely to happen if Fusion fails because renewables like wind and solar are necessitating longer distance transmission lines and the technology for HVDC has become more economical then HVAC, but even then the ‘local’ grid would remain AC while the ‘backbone’ becomes DC.
