Spanish blackout report: Power plants meant to stabilize voltage didn’t

A series of voltage fluctuations and frequency oscillations hit the Iberian power grid on April 28, leading to a major blackout in Spain and Portugal. Grid operators' attempts to stabilize the system inadvertently increased voltages, causing power plants to disconnect and further exacerbating the problem. The Spanish government's investigation revealed inadequate preparation, with only 10 plants scheduled for voltage regulation that day, some of which responded poorly to operators' commands.